Search

Background: Up to 1/2 of outpatients prescribed clozapine may be partially/fully non-adherent, based on therapeutic drug monitoring (TDM). Three indices for measuring partial/full non-adherence are proposed a: 1) clozapine concentration/dose (C/D) ratio which drops to half or more of what is expected in the patient; 2) clozapine/norclozapine ratio that becomes inverted; and 3) clozapine concentration that becomes non-detectable., Methods: These 3 proposed indices are based on a literature review and 17 cases of possible non-adherence from 3 samples: 1) an inpatient study in a Chinese hospital, 2) an inpatient randomized clinical trial in a United States hospital, and 3) and a Uruguayan outpatient study., Results: The first index of non-adherence is a clozapine C/D ratio which is less than half the ratio corresponding to the patient's specific ancestry group and sex-smoking subgroup. Knowing the minimum therapeutic dose of the patient based on repeated TDM makes it much easier to establish non-adherence. The second index is inverted clozapine/norclozapine ratios in the absence of alternative explanations. The third index is undetectable concentrations. By using half-lives, the chronology of the 3 indices of non-adherence was modeled in two patients: 1) the clozapine C/D ratio dropped to ≥1/2 of what is expected from the patient (around day 2); 2) the clozapine/norclozapine ratio became inverted (around day 3); and 3) the clozapine concentration became undetectable by the laboratory (around days 9-11)., Conclusion: Prospective studies should further explore these proposed clozapine indices in average patients, poor metabolizers (3 presented) and ultrarapid metabolizers (2 presented)., Competing Interests: Declaration of competing interest GS has received speaker/consultation fees from HLS Therapeutics and Thermo Fisher. AEAY has received speaker/advisory board fees from Janssen, Abdi İbrahim Otsuka and Nobel, and has received investigator fees from Janssen. CBE received honoraria for conferences from Forum pour la formation médicale, Janssen-Cilag, Lundbeck, Otsuka, Sandoz, Servier, Sunovion, Sysmex Suisse AG, Takeda, Vifor-Pharma, and Zeller in the past 3 years. SRC received speaker/consultation fees from: Janssen-Cilag, Lundbeck, Otsuka and Servier and research funding from Janssen-Cilag, Lundbeck, Otsuka and Gilead. SHK has received research grants from Janssen and Dongwha. JGL has consulted/spoken on behalf of Saladax Biomedical. RMP has received speaker/consultation fees from Eisai, HLS Therapeutics, Jansen, Lundbeck, and Otsuka. HT has received grants from Daiichi Sankyo and Novartis Pharma; speaker's fees from EA. Pharma, Eisai, Kyowa, Janssen, Lundbeck, Meiji Seika Pharma, MSD, Otsuka, Sumitomo Pharma, Takeda, and Yoshitomiyakuhin; and consulting fees from Janssen, Mitsubishi Tanabe Pharma, Ono, and Sumitomo Pharma. CUC has been a consultant and/or advisor to or has received honoraria from: AbbVie, Acadia, Alkermes, Allergan, Angelini, Aristo, Boehringer-Ingelheim, Cardio Diagnostics, Cerevel, CNX Therapeutics, Compass Pathways, Darnitsa, Denovo, Gedeon Richter, Hikma, Holmusk, IntraCellular Therapies, Janssen/J&J, Karuna, LB Pharma, Lundbeck, MedAvante-ProPhase, MedInCell, Merck, Mindpax, Mitsubishi Tanabe Pharma, Mylan, Neurocrine, Newron, Noven, Novo Nordisk, Otsuka, Pharmabrain, PPD Biotech, Recordati, Relmada, Reviva, Rovi, Seqirus, SK Life Science, Sunovion, Sun Pharma, Supernus, Takeda, Teva, and Viatris. He provided expert testimony for Janssen and Otsuka. He served on a Data Safety Monitoring Board for Compass Pathways, Denovo, Lundbeck, Relmada, Reviva, Rovi, Supernus, and Teva. He has received grant support from Janssen and Takeda. He received royalties from UpToDate and is also a stock option holder of Cardio Diagnostics, Mindpax, LB Pharma and Quantic. In the last 3 years, the remaining authors report no conflicts of interest., (Copyright © 2023. Published by Elsevier B.V.)

During weak induction (from smoking and/or valproate co-prescription), clozapine ultrarapid metabolizers (UMs) need very high daily doses to reach the minimum therapeutic concentration of 350 ng/ml in plasma; clozapine UMs need clozapine doses higher than: 1) 900 mg/day in patients of European/African ancestry, or 2) 600 mg/day in those of Asian ancestry. Published clozapine UMs include 10 males of European/African ancestry, mainly assessed with single concentrations. Five new clozapine UMs (two of European and three of Asian ancestry) with repeated assessments are described. A US double-blind randomized trial included a 32-year-old male smoking two packages/day with a minimum therapeutic dose of 1,591 mg/day from a single TDM during open treatment of 900 mg/day. In a Turkish inpatient study, a 30-year-old male smoker was a possible clozapine UM needing a minimum therapeutic dose of 1,029 mg/day estimated from two trough steady-state concentrations on 600 mg/day. In a Chinese study, three possible clozapine UMs (all male smokers) were identified. The clozapine minimum therapeutic dose estimated with trough steady-state concentrations >150 ng/ml was: 1) 625 mg/day, based on a mean of 20 concentrations in Case 3; 2) 673 mg/day, based on a mean of 4 concentrations in Case 4; and 3) 648 mg/day, based on a mean of 11 concentrations in Case 5. Based on these limited studies, clozapine UMs during weak induction may account for 1-2% of clozapine-treated patients of European ancestry and <1% of those of Asian ancestry. A clozapine-to-norclozapine ratio <0.5 should not be used to identify clozapine UMs., Competing Interests: Declaration of competing interest GS has received speaker/consultation fees from HLS Therapeutics and Thermo Fisher. SRC received speaker/consultation fees from: Janssen-Cilag, Lundbeck, Otsuka and Servier and research funding from Janssen-Cilag, Lundbeck, Otsuka and Gilead. SH Kim has received research grants from Janssen and Dongwha. HT has received grants from Daiichi Sankyo and Novartis Pharma; speaker's fees from EA. Pharma, Eisai, Kyowa, Janssen, Lundbeck, Meiji Seika Pharma, MSD, Otsuka, Sumitomo Pharma, Takeda, and Yoshitomiyakuhin; and consulting fees from Janssen, Mitsubishi Tanabe Pharma, Ono, and Sumitomo Pharma. CUC has been a consultant and/or advisor to or has received honoraria from: AbbVie, Acadia, Alkermes, Allergan, Angelini, Aristo, Boehringer-Ingelheim, Cardio Diagnostics, Cerevel, CNX Therapeutics, Compass Pathways, Darnitsa, Denovo, Gedeon Richter, Hikma, Holmusk, IntraCellular Therapies, Janssen/J&J, Karuna, LB Pharma, Lundbeck, MedAvante-ProPhase, MedInCell, Merck, Mindpax, Mitsubishi Tanabe Pharma, Mylan, Neurocrine, Newron, Noven, Novo Nordisk, Otsuka, Pharmabrain, PPD Biotech, Recordati, Relmada, Reviva, Rovi, Seqirus, SK Life Science, Sunovion, Sun Pharma, Supernus, Takeda, Teva, and Viatris. He provided expert testimony for Janssen and Otsuka. He served on a Data Safety Monitoring Board for Compass Pathways, Denovo, Lundbeck, Relmada, Reviva, Rovi, Supernus, and Teva. He has received grant support from Janssen and Takeda. He received royalties from UpToDate and is also a stock option holder of Cardio Diagnostics, Mindpax, LB Pharma and Quantic. In the last 3 years, the remaining authors report no conflicts of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Housing insecurity is associated with co-occurring depression and pain interfering with daily activities. Network analysis of depressive symptoms along with associated risk or protective exposures may identify potential targets for intervention in patients with co-occurring bodily pain. In a community-based sample of adults (n = 408) living in precarious housing or homelessness in Vancouver, Canada, depressive symptoms were measured by the Beck Depression Inventory; bodily pain and impact were assessed with the 36-item Short Form Health Survey. Network and bootstrap permutation analyses were used to compare depressive symptoms endorsed by Low versus Moderate-to-Severe (Mod + Pain) groups. Multilayer networks estimated the effects of risk and protective factors. The overall sample was comprised of 78% men, mean age 40.7 years, with 53% opioid use disorder and 14% major depressive disorder. The Mod + Pain group was characterized by multiple types of pain, more persistent pain, more severe depressive symptoms and a higher rate of suicidal ideation. Global network connectivity did not differ between the two pain groups. Suicidal ideation was a network hub only in the Mod + Pain group, with high centrality and a direct association with exposure to lifetime trauma. Antidepressant medications had limited impact on suicidal ideation. Guilt and increased feelings of failure represented symptoms from two other communities of network nodes, and completed the shortest pathway from trauma exposure through suicidal ideation, to the non-prescribed opioid exposure node. Interventions targeting these risk factors and symptoms could affect the progression of depression among precariously housed patients., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)

Background: Studies have reported positive associations between drug-induced movement disorders (DIMDs) and symptoms of psychosis in patients with schizophrenia. However, it is not clear which subtypes of symptoms are related to each other, and whether one symptom precedes another. The current report assessed both concurrent and temporal associations between DIMDs and symptoms of psychosis in a community-based sample of homeless individuals., Methods: Participants were recruited in Vancouver, Canada. Severity of DIMDs and psychosis was rated annually, allowing for the analysis of concurrent associations between DIMDs and Positive and Negative Syndrome Scale (PANSS) five factors. A brief version of the PANSS was rated monthly using five psychotic symptoms, allowing for the analysis of their temporal associations with DIMDs. Mixed-effects linear and logistic regression models were used to assess the associations., Results: 401 participants were included, mean age of 40.7 years (SD = 11.2) and 77.4% male. DIMDs and symptoms of psychosis were differentially associated with each other, in which the presence of parkinsonism was associated with greater negative symptoms, dyskinesia with disorganized symptoms, and akathisia with excited symptoms. The presence of DIMDs of any type was not associated with depressive symptoms. Regarding temporal associations, preceding delusions and unusual thought content were associated with parkinsonism, whereas dyskinesia was associated with subsequent conceptual disorganization., Conclusions: The current study found significant associations between DIMDs and symptoms of psychosis in individuals living in precarious housing or homelessness. Moreover, there were temporal associations between parkinsonism and psychotic symptoms (delusions or unusual thought content), and the presence of dyskinesia was temporally associated with higher odds of clinically relevant conceptual disorganization., Competing Interests: Declaration of competing interest DDK, AAJ, KMG, PWJ, AMP, LHNL, RMC, WJP, OL, DJL, AET and AMB have no competing interests. RMP has received consulting fees or sat on paid advisory boards for: Janssen, Lundbeck, and Otsuka; is on the speaker's bureau for Janssen, Lundbeck, and Otsuka. WGH has received consulting fees or sat on paid advisory boards for: In Silico (unpaid), Translational Life Sciences, and AbbVie., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objective: Many individuals living in precarious housing or homelessness have multimorbid illnesses, including substance use, psychiatric, and neurological disorders. Movement disorders (MDs) associated substance use are amongst the poorly studied subtopics of drug-induced MDs. The aim of the present study was, therefore, to determine the proportion affected and severity of different signs of MDs, as well as their associations with substance use in a community-based sample of precariously housed and homeless individuals., Methods: Participants were recruited from an impoverished urban neighborhood and were assessed for substance dependence and self-reported substance use (alcohol, cannabis, cocaine, methamphetamine, nicotine, and opioids), as well as for the severity of signs of MDs (akathisia, dyskinesia, dystonia, and parkinsonism). Adjusted regression models were used to estimate the associations of the severity of signs with the frequency of substance use over the past 4 weeks and with the baseline diagnosis of substance dependence., Results: The proportion of the sample with clinically relevant signs of MDs in any of the four categories was 18.6% (n = 401), and these participants demonstrated lower levels of functioning than those without signs. Of the different types of substance use, only methamphetamine (its frequency of use and dependence) was significantly associated with greater severity of overall signs of MDs. Frequency of methamphetamine use significantly interacted with age and sex, whereby older female participants exhibited the greatest overall severity with increased methamphetamine use. Of the different signs of MDs, methamphetamine use frequency was positively associated with the severity of trunk/limb dyskinesia and hypokinetic parkinsonism. Relative to no use, concurrent use of antipsychotics demonstrated lower severity of trunk/limb dyskinesia and greater severity of hypokinetic parkinsonism with methamphetamine use, and greater severity of dystonia with cocaine use., Conclusions: Our study found a high proportion of MDs in a relatively young sample, and their severity was consistently associated with methamphetamine use, moderated by participant demographics and antipsychotic use. These disabling sequelae represent an important and understudied neurological condition that may affect quality of life and will require further study., Competing Interests: Declaration of Competing Interest DD Kim: reports no disclosures relevant to the manuscript. RM Procyshyn: has received consulting fees or sat on paid advisory boards for Janssen, Lundbeck, and Otsuka; is on the speaker's bureau for Janssen, Lundbeck, and Otsuka. LHN Lee: reports no disclosures relevant to the manuscript. WJ Panenka: grant funding from the Canadian Institutes of Health Research, Brain Injury Canada, and ACRM Task Force. JL Stubbs: reports no disclosures relevant to the manuscript. AA Jones: reports no disclosures relevant to the manuscript. LL Cho: reports no disclosures relevant to the manuscript. O Leonova: reports no disclosures relevant to the manuscript. KM Gicas: reports no disclosures relevant to the manuscript. AE Thornton: grant funding from the Canadian Institutes of Health Research, the Simon Fraser University William and Ada Isabelle Steel Research Fund, and the Simon Fraser University Psychology Department Research Grant. DJ Lang: reports no disclosures relevant to the manuscript. GW MacEwan: reports no disclosures relevant to the manuscript. WG Honer: has received consulting fees or sat on paid advisory boards for the Canadian Agency for Drugs and Technology in Health, AlphaSights, Guidepoint, In Silico, Translational Life Sciences (TLS), Otsuka, Lundbeck, and Newron; and holds shares in TLS and Eli Lilly. AM Barr: reports no disclosures relevant to the manuscript., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The approach to analysis of and interpretation of findings from the Beck Depression Inventory (BDI), a self-report questionnaire, depends on sample characteristics. To extend work using conventional BDI scoring, the BDI's suitability in assessing symptom severity in a homeless and precariously housed sample was examined using Rasch analysis. Participants (n=478) recruited from an impoverished neighbourhood in Vancouver, Canada, completed the BDI. Rasch analysis using the partial credit model was done, and the structural validity, unidimensionality, and reliability of the BDI were studied. A receiver operating characteristic curve determined a Rasch cut-off score consistent with clinical depression, and Rasch scores were correlated with raw scores. Good fit to the Rasch model was observed after rescoring all items and removing Item 19 (Weight Loss), and unidimensionality and reliability were satisfactory. Item 9 (Suicidal Wishes) represented the most severe symptom. Rasch-based scores detected clinical depression with moderate sensitivity and specificity, and were positively correlated with conventional scores. The BDI in a community-based sample of homeless and precariously housed adults satisfied Rasch model expectations in a 20-item format, and is suitable for assessing symptom severity. Future research on depression in similar samples may reveal more information on using specific symptoms to determine clinical significance., Competing Interests: Declaration of Competing Interest LLC, AAJ, CG, KMG, OL, TB, AET, DJL, GWM, WJP, and AMB have no competing interests. RMP has received consulting fees or sat on paid advisory boards for: Janssen, Lundbeck, and Otsuka; is on the speaker’s bureau for Janssen, Lundbeck, and Otsuka. FVR receives research support from CIHR, Brain Canada, Michael Smith Foundation for Health Research, Vancouver Coastal Health Research Institute, and Weston Brain Institute for investigator-initiated research. Philanthropic support from Seedlings Foundation. FVR has also received in-kind equipment support for this investigator-initiated trial from MagVenture and honoraria for participation in advisory board for Janssen. WGH has received consulting fees or sat on paid advisory boards for: In Silico (unpaid), Translational Life Sciences, and AbbVie., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Antipsychotics are the only therapeutic class indicated in the symptomatic management of psychotic disorders. However, individuals diagnosed with schizophrenia or schizoaffective disorder may not always benefit from these first-line agents. This refractoriness to conventional treatment can be difficult to address in most clinical settings. Therefore, a referral to a tertiary-care program that is better able to deliver specialized care in excess of the needs of most individuals may be necessary. The average outcome following a period of treatment at these programs tends to be one of improvement. Nonetheless, accurate prognostication of individual-level responses may be useful in identifying those who are unlikely to improve despite receiving specialized care. Thus, the main objective of this study was to predict symptom severity around the time of discharge from the Refractory Psychosis Program in British Columbia, Canada using only clinicodemographic information and prescription drug data available at the time of admission. To this end, a different boosted beta regression model was trained to predict the total score on each of the five factors of the Positive and Negative Syndrome Scale (PANSS) using a data set composed of 320 hospital admissions. Internal validation of these prediction models was then accomplished by nested cross-validation. Insofar as it is possible to make comparisons of model performance across different outcomes, the correlation between predictions and observations tended to be higher for the negative and disorganized factors than the positive, excited, and depressed factors on internal validation. Past scores had the greatest effect on the prediction of future scores across all 5 factors. The results of this study serve as a proof of concept for the prediction of symptom severity using this specific approach., Competing Interests: RP reports personal fees from Janssen, Lundbeck and Otsuka. WH reports personal fees from Canadian Agency for Drugs and Technology in Health, AlphaSights, Guidepoint, Translational Life Sciences, Otsuka, Lundbeck, and Newron; grants from Canadian Institutes of Health Research, BC Mental Health and Addictions Services; and has been a consultant (non-paid) for In Silico. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Lee, Procyshyn, White, Gicas, Honer and Barr.)

Abstract: Pain and related consequences could contribute to comorbid illness and premature mortality in homeless and precariously housed persons. We analyzed longitudinal data from an ongoing naturalistic prospective study of a community-based sample (n = 370) to characterize risk factors and consequences of bodily pain. The aims were to describe bodily pain and associations with symptoms and psychosocial function, investigate factors that may increase or ameliorate pain, and examine the consequences of pain for symptoms, functioning, and all-cause mortality. Bodily pain severity and impact were rated with the 36-item Short Form Health Survey Bodily Pain Scale monthly over 5 years. Mixed-effects linear regression models estimated the effects of time-invariant and time-varying risk factors for pain, verified by reverse causality and multiple imputation analysis. Regression models estimated the associations between overall person-mean pain severity and subsequent functioning and suicidal ideation, and Cox proportional hazard models assessed association with all-cause mortality. Bodily pain of at least moderate severity persisted (>3 months) in 64% of participants, exceeding rates expected in the general population. Greater pain severity was associated with depressive symptom severity and month-to-month opioid use, overlaid on enduring risk associated with age, arthritis, and posttraumatic stress disorder. The frequency of prescribed and nonprescribed opioid use had nonlinear relationships with pain: intermittent use was associated with severe pain, without reverse association or change with the overdose epidemic. Greater longitudinal mean pain severity was associated with premature mortality, poorer functioning, and suicidal ideation. Considering the relationships between pain, intermittent opioid use, and depressive symptoms could improve health care for precariously housed patients., (Copyright © 2022 International Association for the Study of Pain.)

Background: People living in precarious housing or homelessness have higher than expected rates of psychotic disorders, persistent psychotic symptoms, and premature mortality. Psychotic symptoms can be modeled as a complex dynamic system, allowing assessment of roles for risk factors in symptom development, persistence, and contribution to premature mortality., Method: The severity of delusions, conceptual disorganization, hallucinations, suspiciousness, and unusual thought content was rated monthly over 5 years in a community sample of precariously housed/homeless adults ( n = 375) in Vancouver, Canada. Multilevel vector auto-regression analysis was used to construct temporal, contemporaneous, and between-person symptom networks. Network measures were compared between participants with ( n = 219) or without ( n = 156) history of psychotic disorder using bootstrap and permutation analyses. Relationships between network connectivity and risk factors including homelessness, trauma, and substance dependence were estimated by multiple linear regression. The contribution of network measures to premature mortality was estimated by Cox proportional hazard models., Results: Delusions and unusual thought content were central symptoms in the multilevel network. Each psychotic symptom was positively reinforcing over time, an effect most pronounced in participants with a history of psychotic disorder. Global connectivity was similar between those with and without such a history. Greater connectivity between symptoms was associated with methamphetamine dependence and past trauma exposure. Auto-regressive connectivity was associated with premature mortality in participants under age 55., Conclusions: Past and current experiences contribute to the severity and dynamic relationships between psychotic symptoms. Interrupting the self-perpetuating severity of psychotic symptoms in a vulnerable group of people could contribute to reducing premature mortality.

Aim: Long-acting injectable antipsychotic drugs (LAIs) are often used as an alternative to oral antipsychotics (OAPs) in individuals with psychosis who demonstrate poor medication adherence. Previous meta-analyses have found mixed results on the efficacy of LAIs, compared to OAPs, in patients with psychotic disorders. The objective of this meta-analysis was to compare the effectiveness of using LAIs versus OAPs in the early stages of psychosis., Methods: Major electronic databases were used to search for any studies examining the comparative effectiveness (i.e., relapse, adherence, hospitalization, and all-cause discontinuation) of any LAIs versus OAPs in early stages of psychosis. Studies published up to 6 June, 2019 were included and no language restriction was applied. Inclusion criteria were a diagnosis of schizophrenia or related disorder, where patients were in their first episode or had a duration of illness ≤5 years. Data were analysed using a random-effects model., Results: Fifteen studies (n = 10 584) were included, of which were 7 RCTs, 7 observational studies, and 1 post-hoc analysis. We found that LAIs provided advantages over OAPs in terms of relapse rates. No significant differences were found between LAI and OAP groups in terms of all-cause discontinuation, hospitalization, and adherence rates. However, considering only RCTs revealed advantages of LAIs over OAPs in terms of hospitalization rates., Conclusions: LAIs may provide benefits over OAPs with respect to reducing relapse and hospitalization rates in early psychosis patients. There is a need for larger and better-designed studies comparing OAPs and LAIs specifically in early psychosis patients., (© 2021 John Wiley & Sons Australia, Ltd.)

Aim: Long acting injectable (LAI) antipsychotics are an alternative to oral antipsychotic (OAP) treatment and may be beneficial for patients in the early stages of schizophrenia. This study aims to provide a comprehensive review on the efficacy of first-generation and second-generation LAI antipsychotics in recent-onset, first-episode, and early psychosis patients., Methods: MEDLINE, EMBASE, PsycINFO, and Web of Science Core databases were used to search for studies that used LAIs in early psychosis patients. Studies published up to 06 Jun 2019 were included with no language restrictions applied. Inclusion criteria were a diagnosis of schizophrenia or related disorder, where patients were in their first episode or had a duration of illness ≤5 years., Results: 33 studies were included: 8 RCTs, 4 post-hoc analyses, 2 case reports, and 19 naturalistic studies. The majority of studies evaluated risperidone LAIs (N = 14) and paliperidone palmitate (N = 10), while the remainder investigated fluphenazine decanoate (N = 3), flupentixol decanoate (N = 2), and aripiprazole (N = 1). Two studies did not specify the LAI formulation used, and one cohort study compared the efficacy of multiple different LAI formulations., Conclusions: While the majority of data is based on naturalistic studies investigating risperidone LAIs or paliperidone palmitate, LAIs may be an effective treatment for early psychosis patients in terms of adherence, relapse reduction, and symptom improvements. There is still a need to conduct more high quality RCTs that investigate the efficacy of different LAI formulations in early psychosis patients., Competing Interests: WGH has received consulting fees or sat on paid advisory boards for the Canadian Agency for Drugs and Technology in Health, AlphaSights, In Silico (unpaid), Newron, Translational Life Sciences and Otsuka/Lundbeck. RMP has received consulting fees or sat on paid advisory boards for Janssen, Lundbeck and Otsuka; is on the speaker’s bureau for Janssen, Lundbeck and Otsuka. All other authors have no conflict of interest to declare.

This international guideline proposes improving clozapine package inserts worldwide by using ancestry-based dosing and titration. Adverse drug reaction (ADR) databases suggest that clozapine is the third most toxic drug in the United States (US), and it produces four times higher worldwide pneumonia mortality than that by agranulocytosis or myocarditis. For trough steady-state clozapine serum concentrations, the therapeutic reference range is narrow, from 350 to 600 ng/mL with the potential for toxicity and ADRs as concentrations increase. Clozapine is mainly metabolized by CYP1A2 (female non-smokers, the lowest dose; male smokers, the highest dose). Poor metabolizer status through phenotypic conversion is associated with co-prescription of inhibitors (including oral contraceptives and valproate), obesity, or inflammation with C-reactive protein (CRP) elevations. The Asian population (Pakistan to Japan) or the Americas' original inhabitants have lower CYP1A2 activity and require lower clozapine doses to reach concentrations of 350 ng/mL. In the US, daily doses of 300-600 mg/day are recommended. Slow personalized titration may prevent early ADRs (including syncope, myocarditis, and pneumonia). This guideline defines six personalized titration schedules for inpatients: 1) ancestry from Asia or the original people from the Americas with lower metabolism (obesity or valproate) needing minimum therapeutic dosages of 75-150 mg/day, 2) ancestry from Asia or the original people from the Americas with average metabolism needing 175-300 mg/day, 3) European/Western Asian ancestry with lower metabolism (obesity or valproate) needing 100-200 mg/day, 4) European/Western Asian ancestry with average metabolism needing 250-400 mg/day, 5) in the US with ancestries other than from Asia or the original people from the Americas with lower clozapine metabolism (obesity or valproate) needing 150-300 mg/day, and 6) in the US with ancestries other than from Asia or the original people from the Americas with average clozapine metabolism needing 300-600 mg/day. Baseline and weekly CRP monitoring for at least four weeks is required to identify any inflammation, including inflammation secondary to clozapine rapid titration., Competing Interests: In the last 3 years, the following authors had no conflict of interest: Drs. de Leon, Schoretsanitis, Molden, Smith, Solismaa, Švancer, Olmos, Ricciardi, Iglesias-Garcia, Iglesias-Alonso, Spina, Ruan, Chuan-Yue Wang, Gang Wang, Tang, Lin, Lane, Rajkumar, González-Esquivel, Jung-Cook, Baptista, Rohde, Nielsen, Verdoux, Quiles, Sanz, De las Cuevas, Cohen, Schulte, Chopra, McCollum, Shelton, Kaithi, Farooq, McGrane, Lana, Arrojo-Romero, Rădulescu, Every-Palmer, Bebawi, Bhattacharya, Otsuka, Lazary, Torres, Yecora, Motuca, Chan, Zolezzi, Ouanes, De Berardis, Grover, Kirilochev, Soloviev, Ayub, Silva, Bonelli, Temmingh, Decloedt, Pedro, Pacheco Palha, LLerena, Fernandez-Egea, Siskind, Masmoudi, Mohd Saffian, Leung and Buckley. In the last 3 years several authors report conflicts of interests. Dr. Seppälä is permanent medical advisor, received lecture fees and is an advisory board member from Viatris that markets clozapine in Finland and other European countries. Dr. Kopeček participated in speakers/advisory boards and lectured with the support of Angelini, Janssen Pharmaceuticals, Lundbeck and Richter Gedeon. Dr. Yong Sik Kim received grants, research support and honoraria from Janssen, Otsuka, Whan in Pharm and Bukwang Pharm (Sumitomo Dannipon Pharma). Dr. Se Hyun Kim received research grants from and/or served as a lecturer for Janssen, Eli Lilly, and Dongwha. Dr. Ertuğrul has received speaker’s honoraria from Abdi İbrahim Otsuka. Dr. Anıl Yağcıoğlu has received speaker’s honoraria and consulting fees from Janssen and Abdi İbrahim Otsuka. Dr. Cotes has received research funding from Otsuka, Lundbeck, Roche, Alkermes, and is a consultant for Saladax Biomedical. Dr. Kane reports personal fees from Alkermes, personal fees from Allergan, personal fees from Bristol-Myers Squibb, personal fees from IntraCellular Therapies, Janssen, Lundbeck, Minerva, Neurocrine, Otsuka, Pierre Fabre, Reviva, Sunovion, Takeda, Teva, outside-the-submitted work from LB Pharma, MedAvante and The Vanguard Research Group. Dr. Ng had served as consultant for Grunbiotics, Lundbeck, Servier, and Janssen-Cilag, and received research speaker honoraria from Servier, Janssen-Cilag and Pfizer.IMcG received royalties from Hogrefe Publishing Corp. T.L. Dr. Bilbily is supported by the National Institute on Drug Abuse training grant 5T32DA007261-30 (MPI). Dr. Hiemke received speaker’s honoraria from Otsuka. Dr. López-Jaramillo reports financial support for research from Financial support from the National Institute of Mental Health, USA, MinCiencias, Colombia and the Universidad de Antioquia, Colombia. Dr. Eap received honoraria for conferences or teaching CME courses from Janssen-Cilag, Lundbeck, Otsuka, Sandoz, Servier, Sunovion, Vifor-Pharma, and Zeller. Dr. Seifritz has received honoraria from Schwabe GmbH for educational lectures. He has further received educational grants and consulting fees from Janssen Cilag, Lundbeck, Angelini, Otsuka, Servier, Recordati, Vifor, Sunovion, and Mepha. Dr. Bousman is a member of the Clinical Pharmacogenetics Implementation Consortium (CPIC) and Pharmacogene Variation Consortium (PharmVar). Dr. Kelly has served as a consultant for Alkermes, Lyndra and Sunovion. Dr. Procyshyn has been on the speaker's bureau and attended advisory board meetings for Janssen, Lundbeck, and Otsuka. Dr. Adebayo was on the advisory board of Janssen for a Long Acting Injectable Paliperidone palmitate in Nigeria. Janssen is not involved in Clozapine in Nigeria. Dr. Fountoulakis has received grants in the past, served as consultant, advisor or CME speaker, or received support to attend congresses by the following entities: AstraZeneca, Bristol-Myers Squibb, Eli Lilly, Ferrer, Gedeon Richter, Janssen, Lundbeck, Otsuka, Pfizer, the Pfizer Foundation, Sanofi-Aventis, Servier, Shire and others. Since January 2020 he has been the director of Cochrane Greece and completely free from any conflict of interest. Dr. Wilkowska has received research support from Angelini, Biogen, Eli Lilly and Company, Janssen-Cilag, Lundbeck, Polpharma, Sanofi and Valeant. Dr. Cubała has received research support from Alkermes, Allergan, Auspex, Biogen, Celon, Ferrier, Forest Laboratories, Janssen, Otsuka, and Sanofi; he has served on speaker bureaus for Angelini, Celon, Janssen, and Sanofi, and he has served as a consultant for GW Pharmaceuticals, Janssen, Celon and Sanofi. Dr. Villagrán-Moreno has received speakerʼs honoraria from Janssen and have developed lectures and presented clozapine lectures for Adamed, which sells clozapine in Spain; he has participated in advisory boards for Rovi and in research projects for Otsuka. Dr. Crespo-Facorro has received funding unrelated to the present work for research projects and/or honoraria as a consultant or speaker from the following entities: Angelini, Janssen-Cilag, Lundbeck, Otsuka, Mylan, Sanofi-Aventis, ADAMED, Agencia Española de Investigacion, Instituto de Salud Carlos III, the EU Seventh Framework Program and Horizon 2020. Dr. Takeuchi has received speaker’s fees from EA Pharma, Kyowa, Janssen, Lundbeck, Meiji Seika Pharma, Mochida, Otsuka, Sumitomo Dainippon Pharma, Takeda, and Yoshitomiyakuhin. Dr. Tsukahara has received speaker's honoraria from Eisai Inc. Dr. Gründer has served as a consultant for Allergan (Dublin, Ireland), Boehringer Ingelheim (Ingelheim, Germany), Institute for Quality and Efficiency in Health Care (IQWiG, Cologne, Germany), Janssen-Cilag (Neuss, Germany), Lundbeck (Copenhagen, Denmark), Otsuka (Chiyoda, Japan), Recordati (Milan, Italy), Sage (Cambridge, USA), and Takeda (Osaka, Japan). He has served on the speakers’ bureau of Gedeon Richter (Budapest, Hungary), Janssen Cilag, Lundbeck, Otsuka, Recordati. He has received grant support from Boehringer Ingelheim, Lundbeck and Saladax (Bethlehem, USA). He is co-founder and/or shareholder of Mind and Brain Institute GmbH (Zornheim, Germany), Brainfoods GmbH (Zornheim, Germany), OVID Health Systems GmbH (Berlin, Germany) and MIND Foundation gGmbH (Berlin, Germany). Dr. Sagud participated in lectures for the following companies: Alkaloid, Belupo, Elli Lilly, Gedeon Richter, Jadran Galenski Laboratorij, Johnson / Johnson, Lundbeck, Makpharm, Pliva, Stada and participated in the clinical trial: Eli Lilly, Krka and Gedeon Richter. Dr. Celofiga received speaker’s honoraria from Ely Lilly, Lundbeck, Richter Gedeon, Krka, Lek, Pliva, Angelini Pharma and participated in advisory boards for Janssen Pharmaceuticals and Lundbeck. Dr. Ignjatovic Ristic developed and presented clozapine lectures with the support of Mylan, received speakerʼs honoraria from Mylan, Teva Serbia, Pharm Swiss, Krka and Janssen. Dr. Ortiz has been a consultant and has received honoraria from Janssen-Cilag. Dr. Elkis received research grants from the São Paulo Research Support Foundation (FAPESP) and honoraria for participation as a member of advisory boards, speaker, or travel support from the following pharmaceutical companies: Aché, Cristalia, Daiichi-Sankyo, Janssen, Mantecorp-Hypera, Sandoz, and Teva. Dr. Weizman received speakerʼs honoraria from Lundbeck, Lilly, Teva, Trima, Jansen, Medison, Novartis and AstraZeneca. These activities were unrelated to the current study. Dr Marder reports consultation fees from Roche, Sunovion, Merck, Boehringer Ingelheim and Otsuka. He reports research support from Boehringer-Ingelheim, and GW Pharma. Dr. Citrome has engaged in collaborative research with, or received consulting or speaking fees, from: AbbVie, Acadia, Alexza, Alkermes, Allergan, Angelini, Astellas, AstraZeneca, Avanir, Axsome, BioXcel, Boehringer Ingelheim, Bristol-Myers Squibb, Cadent Therapeutics, Eisai, Eli Lilly, Forum, Genentech, Impel, Indivior, Intra-Cellular Therapies, Janssen, Jazz, Karuna, Lundbeck, Luye, Lyndra, Medavante-Prophase, Meiji, Merck, Medivation, Mylan, Neurocrine, NeuroRx, Novartis, Noven, Osmotica, Otsuka, Pfizer, Reckitt Benckiser, Relmada, Reviva, Sage, Shire, Sunovion, Takeda, Teva, University of Arizona, Valeant, Vanda, and one-off ad hoc consulting for individuals/entities conducting marketing, commercial, or scientific scoping research. Dr. Freudenreich has the following financial relationship with a commercial interest to disclose (recipient SELF; content area SCHIZOPHRENIA): Alkermes – Research grant (to institution), consultant honoraria (Advisory Board); Avanir – Research grant (to institution); Janssen – Research grant (to institution), consultant honoraria (Advisory Board); Integral - Consultant honoraria; Neurocrine – Consultant honoraria (Advisory Board); Novartis – Consultant honoraria; Otsuka – Research grant (to institution); Roche – Consultant honoraria; Springer Verlag – Royalties (medical writer); Elsevier – Honoraria (medical editing); Global Medical Education – Honoraria (CME speaker and content developer); Medscape – Honoraria (CME speaker); American Psychiatric Association – Consultant honoraria (SMI Adviser); Wolters-Kluwer – Royalties (content developer); UpToDate – Royalties, honoraria (content developer and editor, including for a chapter on clozapine). Dr. Correll has been a consultant and/or advisor to or has received honoraria from: AbbVie, Acadia, Alkermes, Allergan, Angelini, Aristo, Axsome, Damitsa, Gedeon Richter, Hikma, IntraCellular Therapies, Janssen/J&J, Karuna, LB Pharma, Lundbeck, MedAvante-ProPhase, MedInCell, Medscape, Merck, Mitsubishi Tanabe Pharma, Mylan, Neurocrine, Noven, Otsuka, Pfizer, Recordati, Rovi, Servier, Sumitomo Dainippon, Sunovion, Supernus, Takeda, Teva, and Viatris. He provided expert testimony for Janssen and Otsuka. He served on a Data Safety Monitoring Board for Lundbeck, Rovi, Supernus, and Teva. He has received grant support from Janssen and Takeda. He received royalties from UpToDate and is also a stock option holder of LB Pharma. Dr. Müller reports he has been a co-investigator for two pharmacogenetic studies where genetic test kits were provided as an in-kind contribution by Myriad Neuroscience. He did not receive any payments or any equity, stocks, or options from any pharmacogenetic companies. He is also a co-inventor of two patents assessing risk for antipsychotic-induced weight gain (pending)., (Thieme. All rights reserved.)

Competing Interests: Disclosure The authors report no conflicts of interest in this work.

The second-generation antipsychotic drugs are widely used in the field of psychiatry, for an expanding number of different conditions. While their clinical efficacy remains indispensable, many of the drugs can cause severe metabolic side-effects, resulting in an increased risk of developing cardiometabolic disorders. The physiological basis of these side-effects remains an ongoing area of investigation. In the present study, we examined the potential role of peripheral catecholamines in antipsychotic-induced glucose intolerance. Adult female rats were acutely treated with either the first-generation antipsychotic drug haloperidol (0.1, 0.5 or 1 mg/kg) or the second-generation drugs risperidone (0.25, 1.0 or 2.5 mg/kg), olanzapine (1.5, 7.5 or 15 mg/kg) or clozapine (2, 10 or 20 mg/kg) or vehicle. Fasting glucose levels were measured and then animals were subjected to the intraperitoneal glucose tolerance test. Levels of peripheral norepinephrine, epinephrine and dopamine were concurrently measured in the same animals 75, 105 and 135 min after drug treatment. All antipsychotics caused glucose intolerance, with strongest effects by clozapine > olanzapine > risperidone > haloperidol. Plasma catecholamines were also increased by drug treatment, with greatest effects for norepinephrine and epinephrine caused by clozapine > risperidone > olanzapine > haloperidol. Importantly, there were strong and statistically significant associations between norepinephrine/epinephrine levels and glucose intolerance for all drugs. These findings confirm that increases in peripheral catecholamines co-occur in animals that exhibit antipsychotic-induced glucose intolerance, and these effects are strongly associated with each other, providing further evidence for elevated catecholamines as a substrate for antipsychotic metabolic side-effects., Competing Interests: WH has received consulting fees or sat on paid advisory boards for: Guidepoint, In Silico Biosciences, Translational Life Sciences, AbbVie and Newron. RP has been a member of the following advisory boards in the past 3 years: Janssen, Lundbeck, and Otsuka; a member of the following speaker’s bureaus in the past 3 years: Janssen, Lundbeck, and Otsuka; and received grants from the Canadian Institutes of Health Research. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Boyda, Pham, Huang, Ho, Procyshyn, Yuen, Honer and Barr.)

Competing Interests: R.M. Procyshyn has received consulting fees or sat on paid advisory boards for Janssen, Lundbeck and Otsuka and is on the speakers bureau for Eisai, Janssen, Lundbeck and Otsuka. No other competing interests were declared.

The Iowa Gambling Task (IGT) is a widely used measure of decision making, but its value in signifying behaviors associated with adverse, "real-world" consequences has not been consistently demonstrated in persons who are precariously housed or homeless. Studies evaluating the ecological validity of the IGT have primarily relied on traditional IGT scores. However, computational modeling derives underlying component processes of the IGT, which capture specific facets of decision making that may be more closely related to engagement in behaviors associated with negative consequences. This study employed the Prospect Valence Learning (PVL) model to decompose IGT performance into component processes in 294 precariously housed community residents with substance use disorders. Results revealed a predominant focus on gains and a lack of sensitivity to losses in these vulnerable community residents. Hypothesized associations were not detected between component processes and self-reported health-risk behaviors. These findings provide insight into the processes underlying decision making in a vulnerable substance-using population and highlight the challenge of linking specific decision making processes to "real-world" behaviors., Competing Interests: WH has received consulting fees or sat on Advisory Boards for the Translational Life Sciences (TLS), AlphaSights, GuidePoint, Newron, In silico, AbbVie, and Otsuka and holds shares in TLS and AbCellera. AB has received consulting fees or sat on Advisory Boards for the Bristol-Myers Squibb, Eli Lilly, and Roche. AR has received Advisory Board fees from the Hofmann-La Roche. GM has received consulting fees or sat on paid advisory boards for Apotex, AstraZeneca, BMS, Janssen, Lundbeck, Otsuka, Pfizer, and Sunovion and also received fees for lectures sponsored by the AstraZeneca, BMS, Janssen, Otsuka, and Eli Lilly, and has received grants from the Janssen Pharmaceuticals. RP has received speaking and Advisory Board fees from the Janssen, Lundbeck, and Otsuka. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Baitz, Jones, Campbell, Jones, Gicas, Giesbrecht, Loken Thornton, Barone, Wang, Panenka, Lang, Vila-Rodriguez, Leonova, Barr, Procyshyn, Buchanan, Rauscher, MacEwan, Honer and Thornton.)

Clozapine is a second generation antipsychotic drug that has proven to be helpful in the management of patients with psychotic disorders that are resistant to other medications. Unfortunately, the majority of patients treated with clozapine develop metabolic dysregulation, including weight gain and insulin resistance. There are few treatments available to effectively counter these side-effects. The goal of the present study was to use an established animal model to better understand the nature of these metabolic side-effects and determine whether existing drugs could be used to alleviate metabolic changes. Adult female rats were treated with a range of doses of clozapine (2, 10 and 20 mg/kg) and subjected to the hyperinsulinemic-euglycemic clamp, to measure whole-body insulin resistance. Clozapine dose-dependently decreased the glucose infusion rate, reflecting pronounced insulin resistance. To reverse the insulin resistance, rats were co-treated with the ganglionic blocker mecamylamine (0.1, 1.0 and 5.0 mg/kg) which dose-dependently reversed the effects of 10 mg/kg clozapine. A 1.0 mg/kg dose of mecamylamine independently reversed the large increase in peripheral epinephrine caused by treatment with clozapine. To study the influence of specific adrenoceptors, rats were treated with multiple doses of α 1 (prazosin), α 2 (idazoxan), β 1 (atenolol) and β 2 (butoxamine) adrenoceptor antagonists after the onset of clozapine-induced insulin resistance. Both beta blockers were effective in attenuating the effects of clozapine, while idazoxan had a smaller effect; no change was seen with prazosin. The current results indicate that peripheral catecholamines may play a role in clozapine's metabolic effects and be a target for future treatments., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Early intervention is essential for favorable long-term outcomes in schizophrenia. However, there is limited guidance in the scientific literature on how best to choose between dopamine D 2 receptor (D 2 R) partial agonists and D 2 R antagonists in early stages of schizophrenia. The aim of this meta-analysis was to directly compare D 2 R partial agonists with D 2 R antagonists for efficacy and tolerability, using randomized controlled trials (RCTs) that involved participants diagnosed with first-episode psychosis, schizophrenia, or related psychotic disorders with a duration of illness ≤5 years. Fourteen RCTs, involving 2494 patients, were included in the meta-analysis. Aripiprazole was the only identified D 2 R partial agonist, and was not significantly different from pooled D 2 R antagonists for overall symptom reduction or all-cause discontinuation. However, aripiprazole was more favorable than pooled D 2 R antagonists for depressive symptoms, prolactin levels, and triglyceride levels. Specifically, aripiprazole was more favorable than paliperidone for triglyceride levels and more favorable than risperidone and olanzapine, but less favorable than ziprasidone, for weight gain. In addition, aripiprazole was less favorable for akathisia compared with second-generation D 2 R antagonists, in particular olanzapine and quetiapine, and less favorable for discontinuation due to inefficacy than risperidone. Lastly, aripiprazole was more favorable than haloperidol for various efficacy and tolerability outcomes. In conclusion, aripiprazole's efficacy did not differ substantially from D 2 R antagonists in the early course of schizophrenia, whereas differential tolerability profiles were noted. More double-blind RCTs are required comparing the efficacy and tolerability of aripiprazole as well as other D 2 R partial agonists with D 2 R antagonists in early stages of schizophrenia.

Longitudinal studies of cannabis exposure during early adolescence in the general population frequently report an increased risk of subsequently developing psychotic symptoms or a psychotic illness. However, there is a dearth of knowledge about the effects of early cannabis exposure on psychosis in homeless and precariously housed adults, who represent a population afflicted with high rates of psychosis. The aim of the present study was to examine how early cannabis exposure (by age 15) compared to later first use (after age 15) affected the expression of adult psychosis in this population. Secondary measures of psychopathology, drug use, cognition and brain structure were also collected. 437 subjects were recruited from single room occupancy hotels in the urban setting of the Downtown Eastside of Vancouver, Canada. Psychiatric diagnoses were determined, and psychotic symptom severity was measured with the 5-factor PANSS. Participants completed a battery of neurocognitive tests, and brain structure was assessed using structural and diffusion tensor imaging MRI scans. Results indicated that early cannabis exposure was associated with an increased risk (OR = 1.09, p < .05) of developing substance induced psychosis, whereas later first use increased risk (OR = 2.19, p < .01) of developing schizophrenia or schizoaffective disorder. There was no group difference in neurocognitive function, although differences were observed in the lateral orbitofrontal cortex and white matter tract diffusivity. These findings indicate that early cannabis exposure in this population may increase the risk of developing drug associated psychoses, which could potentially be mediated in part through altered neurodevelopmental brain changes., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Evidence supports the fact that clozapine can induce stressful obsessive-compulsive symptoms (OCS). Although clozapine's robust inhibition of serotonergic neurotransmission is believed to be a key mechanism underlying clozapine-induced OCS, the exact mechanism(s) are not fully understood. Intuitively, it is reasonable to believe that the dose of clozapine is likely related to emergent OCS severity. However, there is conflicting evidence where both positive and inverse relationships have been demonstrated between clozapine dose and emergent OCS severity. Upon examination of clozapine's receptor profile, in particular its affinity for 5-HT 2A and D 2 receptors, we hypothesize that there is a biphasic relationship between clozapine dose and emergent OCS severity. We present here a preliminary analysis of published cases in the literature to support our hypothesis., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Although clozapine is the gold standard for treatment-resistant schizophrenia, more than 30% of patients remain unresponsive to clozapine monotherapy and may benefit from augmentation strategies. Fluvoxamine augmentation of clozapine may be beneficial in treatment resistance because of pharmacokinetic interactions, allowing for lower clozapine dosages with higher clozapine serum levels and an increased clozapine-to-norclozapine ratio, which can modify adverse effects. An augmentation strategy using higher fluvoxamine doses may also improve persistent negative, anxiety, and obsessive-compulsive symptoms through fluvoxamine's serotonergic activity., Methods: Through chart review, we identified 4 cases of patients with treatment-resistant psychosis who underwent high-dose fluvoxamine augmentation of clozapine to target residual negative symptoms, refractory psychosis, anxiety, and obsessive-compulsive symptoms., Findings: This augmentation strategy continued in 2 patients after discharge who showed clinical improvement without significant adverse effects. Two patients experienced adverse effects that led to the fluvoxamine discontinuation. Despite the fact that fluvoxamine augmentation led to symptom improvement in only 2 patients, all patients achieved high serum clozapine levels. Hematologic parameters were monitored in all patients, and no abnormalities were observed. No severe adverse effects of clozapine were experienced., Conclusions: Although high variability of responses and adverse effects were observed during fluvoxamine augmentation to clozapine, this strategy was successful in increasing clozapine serum levels. Through fluvoxamine's serotonergic effects, this strategy may confer benefit to residual negative, obsessive, and anxiety symptoms. Limitations of this case series include the retrospective nature, absence of controls, diversity of diagnoses, multiple interventions in each patient, and lack of masked raters., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

The second generation antipsychotic drug clozapine represents the most effective pharmacotherapy for treatment-resistant psychosis. It is also associated with low rates of extrapyramidal symptoms and hyperprolactinemia compared to other antipsychotic drugs. However, clozapine tends to be underutilized in clinical practice due to a number of disabling and serious side-effects. These are characterized by a constellation of metabolic side-effects which include dysregulation of glucose, insulin, plasma lipids and body fat. Many patients treated with clozapine go on to develop metabolic syndrome at a higher rate than the general population, which predisposes them for Type 2 diabetes mellitus and cardiovascular disease. Treatments for the metabolic side-effects of clozapine vary in their efficacy. There is also a lack of knowledge about the underlying physiology of how clozapine exerts its metabolic effects in humans. In the current review, we focus on key studies which describe how clozapine affects each of the main symptoms of the metabolic syndrome, and cover some of the treatment options. The clinical data are then discussed in the context of preclinical studies that have been conducted to identify the key biological substrates involved, in order to provide a better integrated overview. Suggestions are provided about key areas for future research to better understand how clozapine causes metabolic dysregulation., Competing Interests: WP reports personal fees from Abbatis Bioceuticals, Medipure Pharmaceuticals and is owner of Translational Life Sciences. RP reports personal fees from Janssen, Lundbeck and Otsuka. WH reports personal fees from Canadian Agency for Drugs and Technology in Health, AlphaSights, Guidepoint, Translational Life Sciences, Otsuka, Lundbeck, and Newron, grants from Canadian Institutes of Health Research, BC Mental Health and Addictions Services, and has been a consultant (non-paid) for In Silico. AB has been a scientific advisor to Emerald Health Therapeutics, Cannevert Therapeutics, Global Cannabis Applications Corp, Medipure Pharmaceuticals, Vitality Biopharma and Oakum Cannabis Corp. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Yuen, Kim, Procyshyn, Panenka, Honer and Barr.)

Background: The second generation antipsychotic drugs represent the most common form of pharmacotherapy for schizophrenia disorders. It is now well established that most of the second generation drugs cause metabolic side-effects. Risperidone and its active metabolite paliperidone (9-hydroxyrisperidone) are two commonly used antipsychotic drugs with moderate metabolic liability. However, there is a dearth of preclinical data that directly compares the metabolic effects of these two drugs, using sophisticated experimental procedures. The goal of the present study was to compare metabolic effects for each drug versus control animals., Methods: Adult female rats were acutely treated with either risperidone (0.1, 0.5, 1, 2, 6 mg/kg), paliperidone (0.1, 0.5, 1, 2, 6 mg/kg) or vehicle and subjected to the glucose tolerance test; plasma was collected to measure insulin levels to measure insulin resistance with HOMA-IR. Separate groups of rats were treated with either risperidone (1, 6 mg/kg), paliperidone (1, 6 mg/kg) or vehicle, and subjected to the hyperinsulinemic euglycemic clamp., Results: Fasting glucose levels were increased by all but the lowest dose of risperidone, but only with the highest dose of paliperidone. HOMA-IR increased for both drugs with all but the lowest dose, while the three highest doses decreased glucose tolerance for both drugs. Risperidone and paliperidone both exhibited dose-dependent decreases in the glucose infusion rate in the clamp, reflecting pronounced insulin resistance., Conclusions: In preclinical models, both risperidone and paliperidone exhibited notable metabolic side-effects that were dose-dependent. Differences between the two were modest, and most notable as effects on fasting glucose., Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests: WGH has received consulting fees or sat on paid advisory boards for Otsuka/Lundbeck, Newron, AlphaSights, Guidepoint, Translational Life Sciences and holds shares in Translational Life Sciences and Eli Lilly. He was additionally supported by the Jack Bell Chair in Schizophrenia. RMP has been a member of the following advisory boards in the past 3 years: Janssen, Lundbeck, and Otsuka; a member of the following speaker’s bureaus in the past 3 years: Janssen, Lundbeck, and Otsuka; and received grants from the Canadian Institutes of Health Research. All other authors declare that no competing interests exist. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Background: opioid use, which includes both prescribed and non-prescribed drugs, is relatively common amongst marginalized populations. Past research has shown that among those who use non-prescribed or diverted opioids recreationally, many were first exposed to the drug as prescribed pain medication. Objective : to better understand the relationship between pain and opioid use in tenants of precarious housing. Methods : in the present study, 440 individuals from a cohort living in homeless or precariously housed conditions in a neighborhood with high rates of poverty and drug use were interviewed for their bodily pain and opioid use. We examined the relationship between bodily pain levels, assessed using the Maudsley Addiction Profile questionnaire, and prescribed, non-prescribed and combined self-reported opioid use in the prior 28 days assessed using the Timeline Followback and Doctor-Prescribed Medication Timeline Followback questionnaires. Results : Analysis of the results indicated that sex (female), age (younger) and early exposure to opioids (≤ age 18) predicted current opioid use, but there was no association between current bodily pain levels and opioid use. Conclusions : these unexpected findings indicate the complex nature of the relationship between pain and opioid use in this population.

Antipsychotic drugs represent the most effective treatment for chronic psychotic disorders. The newer second generation drugs offer the advantage of fewer neurological side-effects compared to prior drugs, but many cause serious metabolic side-effects. The underlying physiology of these side-effects is not well-understood, but evidence exists to indicate that the sympathetic nervous system may play an important role. In order to examine this possibility further, we treated separate groups of adult female rats acutely with either the first generation antipsychotic drug haloperidol (0.1 or 1 mg/kg) or the second generation drugs risperidone (0.25 or 2.5 mg/kg), clozapine (2 or 20 mg/kg), olanzapine (3 or 15 mg/kg) or vehicle by intraperitoneal injection. Blood samples were collected prior to drug and then 30, 60, 120, and 180 mins after treatment. Plasma samples were assayed by HPLC-ED for levels of norepinephrine, epinephrine, and dopamine. Results confirmed that all antipsychotics increased peripheral catecholamines, although this was drug and dose dependent. For norepinephrine, haloperidol caused the smallest maximum increase (+158%], followed by risperidone (+793%), olanzapine (+952%) and clozapine (+1,684%). A similar pattern was observed for increases in epinephrine levels by haloperidol (+143%], olanzapine (+529%), risperidone (+617%) then clozapine (+806%). Dopamine levels increased moderately with olanzapine [+174%], risperidone [+271%], and clozapine [+430%]. Interestingly, levels of the catecholamines did not correlate strongly with each other prior to treatment at baseline, but were increasingly correlated after treatment as time proceeded. The results demonstrate antipsychotics can potently regulate peripheral catecholamines, in a manner consistent with their metabolic liability., Competing Interests: WH has received consulting fees or sat on paid advisory boards for Otsuka/Lundbeck, Newron, AlphaSights, Guidepoint, Translational Life Sciences and holds shares in Translational Life Sciences and Eli Lilly. He was additionally supported by the Jack Bell Chair in Schizophrenia. RP has been a member of the following advisory boards in the past 3 years: Janssen, Lundbeck, and Otsuka; a member of the following speaker's bureaus in the past 3 years: Janssen, Lundbeck, and Otsuka; and received grants from the Canadian Institutes of Health Research. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Boyda, Ho, Tse, Procyshyn, Yuen, Kim, Honer and Barr.)

Rationale: The second generation antipsychotic drug clozapine is a psychotherapeutic agent with superior efficacy for treatment-resistant schizophrenia. Clozapine is associated with a low likelihood of neurological side-effects, but a high propensity to induce weight gain and metabolic dysregulation. The primary metabolite of clozapine is norclozapine (N-Desmethylclozapine), which has psychoactive properties itself, but its effects on metabolic function remains unknown. The goal of the present study was to determine whether directly administered norclozapine could cause metabolic dysregulation, similar to clozapine., Methods: Adult female rats were treated with a range of doses of clozapine and norclozapine (0.5, 2, 8 & 20 mg/kg, i.p.) and then subjected to the intraperitoneal glucose tolerance test (IGTT), where glucose levels were recorded for 2 h following a glucose challenge. In parallel, rats were tested with two doses of clozapine and norclozapine (2 & 20 mg/kg, i.p.) in the hyperinsulinemic-euglycemic clamp (HIEC), to measure whole body insulin resistance., Results: In the IGTT, clozapine demonstrated dose-dependent effects on fasting glucose levels and total glucose area-under-the-curve following the glucose challenge, with the two highest doses strongly increasing glucose levels. Only the highest dose of norclozapine increased fasting glucose levels, and caused a non-significant increase in glucose levels following the challenge. By contrast, both doses of clozapine and norclozapine caused a potent and long-lasting decrease in the glucose infusion rate in the HIEC, indicating that both compounds cause whole body insulin resistance., Abstract: While not as potent as its parent compound, norclozapine clearly exerts acute metabolic effects, particularly on insulin resistance. This article is part of the issue entitled 'Special Issue on Antipsychotics'., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: The "trimorbidity" of substance use disorder and mental and physical illness is associated with living in precarious housing or homelessness. The extent to which substance use increases risk of psychosis and both contribute to mortality needs investigation in longitudinal studies., Methods and Findings: A community-based sample of 437 adults (330 men, mean [SD] age 40.6 [11.2] years) living in Vancouver, Canada, completed baseline assessments between November 2008 and October 2015. Follow-up was monthly for a median 6.3 years (interquartile range 3.1-8.6). Use of tobacco, alcohol, cannabis, cocaine, methamphetamine, and opioids was assessed by interview and urine drug screen; severity of psychosis was also assessed. Mortality (up to November 15, 2018) was assessed from coroner's reports and hospital records. Using data from monthly visits (mean 9.8, SD 3.6) over the first year after study entry, mixed-effects logistic regression analysis examined relationships between risk factors and psychotic features. A past history of psychotic disorder was common (60.9%). Nonprescribed substance use included tobacco (89.0%), alcohol (77.5%), cocaine (73.2%), cannabis (72.8%), opioids (51.0%), and methamphetamine (46.5%). During the same year, 79.3% of participants reported psychotic features at least once. Greater risk was associated with number of days using methamphetamine (adjusted odds ratio [aOR] 1.14, 95% confidence interval [CI] 1.05-1.24, p = 0.001), alcohol (aOR 1.09, 95% CI 1.01-1.18, p = 0.04), and cannabis (aOR 1.08, 95% CI 1.02-1.14, p = 0.008), adjusted for demographic factors and history of past psychotic disorder. Greater exposure to concurrent month trauma was associated with increased odds of psychosis (adjusted model aOR 1.54, 95% CI 1.19-2.00, p = 0.001). There was no evidence for interactions or reverse associations between psychotic features and time-varying risk factors. During 2,481 total person years of observation, 79 participants died (18.1%). Causes of death were physical illness (40.5%), accidental overdose (35.4%), trauma (5.1%), suicide (1.3%), and unknown (17.7%). A multivariable Cox proportional hazard model indicated baseline alcohol dependence (adjusted hazard ratio [aHR] 1.83, 95% CI 1.09-3.07, p = 0.02), and evidence of hepatic fibrosis (aHR 1.81, 95% CI 1.08-3.03, p = 0.02) were risk factors for mortality. Among those under age 55 years, a history of a psychotic disorder was a risk factor for mortality (aHR 2.38, 95% CI 1.03-5.51, p = 0.04, adjusted for alcohol dependence at baseline, human immunodeficiency virus [HIV], and hepatic fibrosis). The primary study limitation concerns generalizability: conclusions from a community-based, diagnostically heterogeneous sample may not apply to specific diagnostic groups in a clinical setting. Because one-third of participants grew up in foster care or were adopted, useful family history information was not obtainable., Conclusions: In this study, we found methamphetamine, alcohol, and cannabis use were associated with higher risk for psychotic features, as were a past history of psychotic disorder, and experiencing traumatic events. We found that alcohol dependence, hepatic fibrosis, and, only among participants <55 years of age, history of a psychotic disorder were associated with greater risk for mortality. Modifiable risk factors in people living in precarious housing or homelessness can be a focus for interventions., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: WGH has received consulting fees or sat on paid advisory boards for In Silico, Otsuka/Lundbeck, Newron, AlphaSights, the Centre for Drug Research and Development, and the Canadian Agency for Drugs and Technology in Health. He was additionally supported by the Jack Bell Chair in Schizophrenia. FVR received research support from Canadian Institutes of Health Research (CIHR), Brain Canada, Michael Smith Foundation for Health Research, and Vancouver Coastal Health Research Institute; received in-kind equipment support for this investigator-initiated trial from MagVenture; and has been on an advisory board for Janssen. RMP has been a member of the following advisory boards in the past 3 years: Janssen, Lundbeck, and Otsuka; a member of the following speaker’s bureaus in the past 3 years: Janssen, Lundbeck, and Otsuka; and received grants from the Canadian Institutes of Health Research. GWM has received consulting fees or sat on paid advisory boards for: Apotex, AstraZeneca, BMS, Janssen, Lundbeck, Otsuka, Pfizer, and Sunovion. He also received fees for lectures sponsored by AstraZeneca, BMS, Janssen, Otsuka, and Eli Lilly, and has received grants from Janssen Pharmaceuticals. JSGM has received institutional grants from Gilead Sciences, J&J, Merck, ViiV Healthcare, and a Knowledge Translation Award from the Canadian Institutes of Health Research. JSGM has also served as an advisor to Government of Canada and the Government of British Columbia in the last year. AET has received grants from the Canadian Institutes of Health Research (CIHR) and the William and Ada Isabelle Steel Fund. This does not alter our adherence to PLOS Medicine policies on sharing data and materials. AAJ, KMG, SS, TSW, OL, GNS, TAS, ATV, TB, AR, DJL, VDL, WJP, and AMB declared that no competing interests exist.

Background: Homeless and precariously housed individuals experience a high burden of comorbid illnesses, and excess mortality. Cross-sectional studies report a high rate of cognitive impairment. Long-term trajectories have not been well investigated in this group., Aims: To longitudinally assess risks for premature and/or accelerated cognitive ageing, and the relationship with early mortality in homeless and precariously housed people., Method: This is a 9-year community-based study of 375 homeless and precariously housed individuals from Vancouver, Canada. Annual cognitive testing assessed verbal learning and memory, and inhibitory control. Linear mixed-effects models examined associations between clinical risk factors (traumatic brain injury, psychotic disorders, viral exposure, alcohol dependence) and cognitive change over 9 years. Cox regression models examined the association between cognition and mortality., Results: Traumatic brain injury and alcohol dependence were associated with decline in verbal memory. Inhibitory control declined, independent of risk factors and to a greater extent in those who died during the study. Better inhibitory control was associated with a 6.6% lower risk of mortality at study entry, with a 0.3% greater effect for each year of life. For each one-point increase in the Charlson Comorbidity Index score at study entry, the risk of mortality was 9.9% higher, and was consistent across age. Adjusting for comorbidities, inhibitory control remained a significant predictor of mortality., Conclusions: Findings raise the possibility of a premature onset, and accelerated trajectory, of cognitive ageing in this group of homeless and precariously housed people. Traumatic brain injury, alcohol dependence and cognition could be treatment priorities.

Aerobic exercise has been associated with hippocampal plasticity, both in healthy adults and in psychosis patients, but its impact on cortical regions remains unclear. The entorhinal cortex serves as a critical gateway for the hippocampus, and recent studies suggest that this region may also be impacted following an exercise regime. In order to investigate the effects of antipsychotic medications and exercise on the entorhinal cortex, female rats were chronically administered either olanzapine or vehicle and were either sedentary or had access to a running wheel for 9 weeks. Olanzapine-treated rats had decreased medial entorhinal cortical thickness compared to vehicle-treated rats. A statistically significant interaction was observed for layer II of the entorhinal cortex, with exercising rats having significantly greater thickness compared to sedentary rats in the vehicle group, but not the olanzapine group. Greater total entorhinal and lateral entorhinal cortical thickness was associated with greater average activity. In exercising rats, decreasing glucose intolerance was associated with larger total entorhinal and layer II cortical thickness. Lower fasting insulin levels were associated with greater total entorhinal, lateral entorhinal, and layer II cortical thickness. The relationship between increased activity and greater entorhinal cortical thickness was mediated by reduced fasting insulin, indicating that regulation of metabolic risk factors may contribute to impact of aerobic exercise on the entorhinal cortex. Aerobic exercise may be helpful in counteracting metabolic side effects of antipsychotic medications and managing these side effects may be key to promoting entorhinal cortical plasticity in patients treated with second-generation antipsychotic drugs., (Crown Copyright © 2019. Published by Elsevier Inc. All rights reserved.)

Background: It is not uncommon to find obsessive-compulsive symptoms (OCS) in patients treated with clozapine. These symptoms are attributed to anti-serotonergic effects of clozapine. The objective of this study was to conduct a systematic review of reported cases of clozapine-associated OCS to better understand the nature and management of these symptoms., Methods: MEDLINE, Embase, and PsycINFO databases were searched with no publication year or language restrictions. Studies reporting cases of clozapine-associated OCS, either de novo or exacerbation of preexisting OCS, were included. The final search date was July 11, 2019., Results: Fifty-seven studies, involving 107 cases (75 de novo, 32 exacerbated OCS), were included. Clozapine triggered moderate-severe OCS at varying doses (100-900 mg/day) and treatment durations (median 6 months, interquartile range 2-24 months). Higher severity was significantly associated with preexisting OCS, poorer insight into OCS, and active psychosis at the time of OCS. Common strategies to treat clozapine-associated OCS included adding selective serotonin reuptake inhibitors, clomipramine, or aripiprazole, often accompanied by clozapine dose reduction. The rate of response to antidepressants was 49% (29/59), where younger age, shorter duration of underlying illness, shorter cloza-pine treatment duration, better insight into OCS, and presence of taboo thoughts were significantly associated with antidepressant response. Subsequent clozapine dose reduction was effective in many non-responders, where aripiprazole was simultaneously added in 50% (8/16)., Conclusions: Clozapine can trigger severe OCS. Adding aripiprazole with/without clozapine dose reduction may be a good alternative to antidepressants for managing clozapine-associated OCS. Clinicians should be more vigilant about these adverse effects and administer appropriate treatments., (© 2020 S. Karger AG, Basel.)

Rationale: Schizophrenia and stimulant-induced psychosis (SIP) represent two different forms of psychotic disorder, with different etiologies. While many of the symptoms of psychosis are common to both disorders, there have been few direct comparisons between these conditions, especially when controlling for stimulant use in individuals with schizophrenia., Objectives: We directly compared both psychotic disorders with a comprehensive battery of clinical, neurocognitive and neuroanatomical measures. This included one group with SIP (and concurrent stimulant dependence) and two groups with schizophrenia (either with or without concurrent stimulant dependence)., Methods: Ninety-six participants were recruited from a marginalized urban population, which included 39 with SIP (and concurrent stimulant dependence), 18 with schizophrenia (without stimulant dependence), and 39 with schizophrenia (with concurrent stimulant dependence). All subjects had extensive clinical and neurocognitive evaluations, complemented with structural MRI including diffusion tensor imaging (DTI) sequences to determine regional brain volumes and white matter connectivity., Results: Both positive and negative symptoms were greater in the SZ-dependent group than the other two. Neurocognitive function was broadly similar. The structural brain imaging revealed lateralized changes to the left parietal/temporal lobe, in which regional volumes were smaller in the SZ-dependent than the SZ-non-dependent group. DTI analysis indicated extensive decreases in fractional anisotropy, with parallel increases in radial diffusivity, in the SIP group compared to the SZ-dependent group., Conclusions: These findings reveal both similarities and differences between SIP and schizophrenia. Furthermore, schizophrenia with concurrent stimulant dependence may be associated with a different clinical and neuroanatomical profile as compared to schizophrenia alone.

Background: Cannabis is commonly used for its medical properties. In particular, cannabis is purported to have beneficial effects on a wide range of neuropsychiatric conditions. Studies assessing mental health in cannabis dispensary users typically evaluate symptoms using self-report check lists, which provide limited information about symptom severity, and whether subjects meet criteria for a psychiatric diagnosis. There is, therefore, a need for studies which assess mental health in dispensary users with standardized and well validated scientific instruments, such as those used in clinical drug trials., Methods: One hundred medical cannabis users were recruited from a community dispensary. All subjects completed a structured clinical interview with the Mini-International Neuropsychiatric Interview (MINI). Subjects also completed the Perceived Stress Scale-10, PROMIS Fatigue Scale, PROMIS Sleep Disturbance Scale, Beck Depression Inventory, the Patient Health Questionnaire-15 and the Brief Pain Inventory. Details about cannabis use were also recorded., Results: Lifetime prevalence of mental illness in this cohort was high, and a large proportion of subjects endorsed psychological symptoms. The proportion of subjects who met criteria for classification of a current psychiatric disorder was low for mood disorders, but high for anxiety disorders and substance abuse/dependence. Cannabis use differed between the main psychiatric conditions., Conclusions: The present results indicate that rates of mental illness may be high in medical cannabis dispensary users. Use of structured clinical assessments combined with standardized symptom severity questionnaires provide a feasible way to provide a more rigorous and detailed evaluation of conditions and symptoms in this population.

Objective: Homeless and marginally housed youth are particularly vulnerable members of society, and are known to experience numerous health problems, including psychiatric illness, substance use, and viral infection. Despite the presence of these risk factors for cognitive compromise, there is limited research on the cognitive functioning of homeless and marginally housed youth. The present study examines the degree and pattern of cognitive impairment and associations with key risk factors in a sample of marginally housed young adults. Method: Participants ( N = 101) aged 20-29 years old were recruited from single-room occupancy hotels, and underwent cognitive, psychiatric, neurological, and serological assessments. Results: Forty percent of participants were identified as mildly cognitively impaired across multiple domains, and 16% were moderately-severely impaired. Deficits in memory and attention were most prevalent, while impairments in inhibitory control/processing speed and cognitive flexibility were also present but tended to be less severe. Developmental and historical factors (premorbid intellectual functioning, neurological soft signs, earlier exposure to and longer duration of homelessness or marginal housing), as well as current health risks (stimulant dependence and hepatitis C exposure), were associated with cognitive impairment. Conclusions: The strikingly high rate of cognitive impairment in marginally housed young adults represents a major public health concern and is likely to pose a significant barrier to treatment and rehabilitation. These results suggest that the pathway to cognitive impairment involves both developmental vulnerability and modifiable risk factors. This study highlights the need for early interventions that address cognitive impairment and risk factors in marginalized young people., (Copyright © 2019 Waclawik, Jones, Barbic, Gicas, O'Connor, Smith, Leonova, Mathias, Barr, Procyshyn, Lang, Woodward, MacEwan, Panenka, Yamamoto, Honer and Thornton.)

Competing Interests: R. Procyshyn has received consulting fees or sat on paid advisory boards for Janssen, Lundbeck and Otsuka; and is on the speaker’s bureau for Janssen, Lundbeck and Otsuka. P. Tibbo has received speaking fees and sat on paid advisory boards for Janssen, Lundbeck, Otsuka and Sunovion. D. Kim and L. Downing declare no competing interests.

Introduction: Cognition is impaired in homeless and vulnerably housed persons. Within this heterogeneous and multimorbid group, distinct profiles of cognitive dysfunction are evident. However, little is known about the underlying neurobiological substrates. Imaging structural covariance networks provides a novel investigative strategy to characterizing relationships between brain structure and function within these different cognitive subgroups., Method: Participants were 208 homeless and vulnerably housed persons. Cluster analysis was used to group individuals on the basis of similarities in cognitive functioning in the areas of attention, memory, and executive functioning. The principles of graph theory were applied to construct two brain networks for each cognitive group, using measures of cortical thickness and gyrification. Global and regional network properties were compared across networks for each of the three cognitive clusters., Results: Three cognitive groups were defined by: higher cognitive functioning across domains (Cluster 1); lower cognitive functioning with a decision-making strength (Cluster 3); and an intermediate group with a relative executive functioning weakness (Cluster 2). Between-group differences were observed for cortical thickness, but not gyrification networks. The lower functioning cognitive group exhibited higher segregation and reduced integration, higher centrality in select nodes, and less spatially compact modules compared with the two other groups., Conclusions: The cortical thickness network differences of Cluster 3 suggest that major disruptions in structural connectivity underlie cognitive dysfunction in a subgroup of people who have a high multimorbid illness burden and who are vulnerably housed or homeless. The origins, and possible plasticity of these structure-function relationships identified with network analysis warrant further study., Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests: WGH has received consulting fees or sat on paid advisory boards for In Silico, Otsuka/Lundbeck, Newron, AlphaSights, the Centre for Drug Research and Development, and the Canadian Agency for Drugs and Technology in Health. He was additionally supported by the Jack Bell Chair in Schizophrenia. FVR received research support from Canadian Institutes of Health Research (CIHR), Brain Canada, Michael Smith Foundation for Health Research, and Vancouver Coastal Health Research Institute; received in-kind equipment support for this investigator-initiated trial from MagVenture; and has been on an advisory board for Janssen. RMP has been a member of the following advisory boards in the past 3 years: Janssen, Lundbeck, and Otsuka; a member of the following speaker’s bureaus in the past 3 years: Janssen, Lundbeck, and Otsuka; and received grants from the Canadian Institutes of Health Research. GWM has received consulting fees or sat on paid advisory boards for: Apotex, AstraZeneca, BMS, Janssen, Lundbeck, Otsuka, Pfizer, and Sunovion. He also received fees for lectures sponsored by AstraZeneca, BMS, Janssen, Otsuka, and Eli Lilly, and has received grants from Janssen Pharmaceuticals. AET has received grants from the Canadian Institutes of Health Research (CIHR) and the William and Ada Isabelle Steel Fund. This does not alter our adherence to PLOS ONE policies on sharing data and materials. KMG, AAJ, WJP, CJG, DJL, OL, AMB, WS, AR, ATV, and TB declared that no competing interests exist.

Objective: Persons who are homeless or marginally housed exhibit significant cognitive dysfunction, with memory being the most impaired domain. Hippocampal subfield volumes have been found to differentially relate to component processes of memory. The neural correlates of memory have not been previously examined in marginalized persons who are understudied and underserved. We examined whether hippocampal subfields and entorhinal cortex volumes are uniquely related to indices of verbal episodic memory using the Hopkins Verbal Learning Test - Revised., Method: Data was used from a large sample of community dwelling homeless and marginally housed adults (N = 227). Regression analyses were conducted to examine hippocampal subfield volumes (CA1, CA3, CA4, dentate gyrus, subiculum) and entorhinal cortex, and their associations with measures of verbal immediate recall, learning slope, and verbal delayed recall., Results: Greater CA3 subfield volume was associated with better performance on an index of encoding (immediate recall), but only in older individuals. Greater CA1 and subiculum volumes were associated with better performance on immediate and delayed recall (measures that tap into retrieval processes), but not with learning slope (a more pure index of encoding). Entorhinal cortex volume was related to all components of memory beyond total hippocampal volume., Conclusions: Our results suggest common neuroanatomical correlates of memory dysfunction in large sample of marginalized persons, and these are uniquely related to different components of memory. These findings have clinical relevance for marginalized populations and theoretical relevance to the growing literature on functional specialization of the hippocampal subfields., (© The Author(s) 2018. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: We investigated white matter differences associated with distinct neurocognitive profiles derived from a large cohort of marginally housed persons with comorbid physical and mental illnesses. Our prior work identified three profile cluster groups: a high functioning group (Cluster 1), a low functioning group with relative strength in decision-making (Cluster 3), and an intermediary group with a relative decision-making weakness (Cluster 2). This study extends previous findings of cortical gray matter differences between these groups with evidence for putative neurodevelopmental abnormalities in the low cognitive functioning group (i.e., Cluster 3). We hypothesized that altered white matter diffusion would be associated with the lowest functioning neurocognitive profile and would be associated with previously observed gray matter differences., Method: Participants from a socially impoverished neighborhood in Vancouver, Canada underwent neurocognitive evaluation and neuroimaging. We performed Tract-Based Spatial Statistics using diffusion tensor imaging data from 184 participants to examine whole-brain differences in white matter microstructure between cluster analytically derived neurocognitive profiles, as well as unitary neurocognitive measures. Correlations between frontal gray and white matter were also examined., Results: Cluster 3 showed increased diffusion in predominately bilateral frontal and interhemisphere tracts (vs. Clusters 1 and 2), with relatively greater diffusion in the left hemisphere (vs. Cluster 1). Differences in radial diffusivity were more prominent compared with axial diffusivity. A weak association between regional frontal fractional anisotropy and previously defined abnormalities in gyrification was observed., Conclusions: In a socially marginalized sample, we established several patterns in the covariation of white matter diffusion and neurocognitive functioning. These patterns elucidate the neurobiological substrates and vulnerabilities that are apt to underlie functional impairments inherent to this complex and heterogeneous population., (© 2019 The Authors. Brain and Behavior published by Wiley Periodicals, Inc.)

Paliperidone palmitate is a second generation antipsychotic, approved for the treatment of schizophrenia in the form of the long-acting injectable (LAI) products INVEGA SUSTENNA® (once monthly injection) and INVEGA TRINZA® (once every 3 months injection). Paliperidone palmitate dissolves slowly after deep intramuscular injection before being hydrolyzed to paliperidone and absorbed into the systemic circulation. The pharmacokinetic (PK) profile of the INVEGA SUSTENNA® formulation is biphasic, comprised of an initial relatively fast zero-order input, which allows rapid attainment of therapeutic concentrations without oral supplementation; and a subsequent maintained second-stage, first-order input, allowing for once monthly administration. Changes to the manufacturing processes can substantially alter the release characteristics of paliperidone palmitate LAI and consequently its PK profile. As an example, larger or smaller particle sizes of paliperidone palmitate can result in a delayed or accelerated release of paliperidone into the systemic circulation, respectively. Such changes are clinically relevant, as transient excursions above therapeutic plasma concentrations can be associated with an increased risk of adverse effects, including tachycardia, hypotension, QT prolongation, and extrapyramidal symptoms. Conversely, a delay in attaining therapeutic plasma concentrations of paliperidone on initiation of treatment, or a return to low plasma concentrations before the end of a dosing interval during repeated dosing, increases the risk of relapse. Given the integral relationship of the PK profile to the product's clinical effects, it is important to have bioequivalence standards that reflect the complexity of the paliperidone palmitate LAI PK profile if one is to consider therapeutic equivalence based on simple bioequivalence testing. Although both the EMA and U.S. FDA have product-specific guidelines to determine bioequivalence, their requirements differ substantially. In Canada, no LAI product-specific bioequivalence guidance exists for multiphasic medication delivery systems, and the recently revised Comparative Bioavailability Standards: Formulations Used for Systemic Effects guidance applies only to oral and non-injectable formulations. We recommend that new Canadian standards be developed for multiphasic and biphasic intramuscular / subcutaneous (IM/SC) products, including paliperidone palmitate LAI products, because, similar to modified-release oral dosage forms, a different PK profile in modified-release IM/SC products can result in clinically meaningful differences in safety, efficacy, and tolerability. To ensure bioequivalence for both newly initiated and switch patients, this paper proposes bioequivalence standards that could be adopted in Canada that include two studies, a multiple-dose cross-over study, and a single-dose study with partial AUC metrics.

Metabolic abnormalities are serious health problems in individuals with schizophrenia. Paradoxically, studies have noted an association where individuals who gained body weight or who have increased their serum lipids demonstrated a better antipsychotic response. As serum lipids serve as more specific physiological markers than body weight, the objective of this study was to review studies that examined the association between changes in serum lipids and changes in symptoms during antipsychotic treatment in individuals with schizophrenia. A Medline® literature search was performed. Fourteen studies were included and analyzed. Evidence suggests that increases in serum lipids may be associated with decreases in symptoms during antipsychotic treatment. This inverse association may be independent of confounding variables, such as weight gain, and may be most evident during treatment with clozapine. Also, according to recent randomized controlled trials, lipid-lowering agents do not appear to worsen symptoms although this needs to be further investigated in clozapine-treated patients. Future studies should investigate the association in question in a larger population and identify underlying mechanisms., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Competing Interests: A. Barr has received grants from Bristol-Myers Squibb and the Canadian Institutes of Health Research. R. White has received consulting fees or sat on paid advisory boards for Janssen, Lundbeck and Otsuka and has received a grant from ThermoFisher/Affymetrix. W. Honer has received consulting fees or sat on paid advisory boards for the Canadian Agency for Drugs and Technology in Health, the Centre for Drug Research and Development, AlphaSights, In Silico (unpaid) and Otsuka/Lundbeck. R. Procyshyn has received consulting fees or sat on paid advisory boards for Janssen, Lundbeck and Otsuka; is on the speaker’s bureau for Janssen, Lundbeck and Otsuka; and has received grants from the Canadian Institutes of Health Research. D. Kim has no conflict of interest to declare.

Background: Although antipsychotics are used to treat Tourette syndrome, there have been reports of paradoxical induction of tics by first- and second-generation antipsychotics., Objective: The objective of this systematic review was to better characterize tics as the potential adverse effect of antipsychotics., Methods: A literature search was performed, with no language restriction, using the MEDLINE, EMBASE, and PsycINFO databases for all publications up to January 2018. To be included, studies utilizing any study design had to meet the following criteria: (1) a temporal association of tics with antipsychotic use where tics emerged during treatment or after discontinuation and (2) no diagnosis of Tourette syndrome before tic emergence. More stringent criteria were used for individuals under 18 years of age that included (1) no personal or family history of primary tic disorder and either (2) tics occurring during antipsychotic treatment improved significantly upon discontinuation or dose reduction or (3) tics emerged after discontinuation of at least 3 months of antipsychotic treatment. Data were extracted according to: age, sex, diagnosis, personal history of motor symptoms or family history of tics, antipsychotic type and dose, treatment duration, types of symptoms emerged, treatment strategies, and follow-up. A Fisher's exact test was used to compare the occurrence of symptoms between first- and second-generation antipsychotic users., Results: The search identified 1290 articles, of which 92 full-text articles were assessed leading to the inclusion of 50 articles. Most of the included articles were case reports or series, involving a total of 60 cases. Thirty cases were associated with treatment with first-generation antipsychotics, 27 with second-generation antipsychotics, and three with a combination of first- and second-generation antipsychotics. Antipsychotics were being used to treat schizophrenia in 60% of the cases and other indications included developmental, behavioral, and mood or anxiety disorders. Tics occurred during treatment (n = 44) or following treatment discontinuation (n = 16). The occurrence of vocal tics with or without motor tics was significantly higher in the first- vs. second-generation antipsychotic users (p < 0.0001). Significantly higher occurrences were also noted in the first- vs. second-generation antipsychotic users for specific types of vocal tics (i.e., barking and coprolalia) and other concurrent motor symptoms (i.e., tardive dyskinesia). In the cases identified, antipsychotic-associated tics were treated by (1) discontinuing the offending antipsychotic, reducing its dose, or switching to different antipsychotics for tics occurring during treatment, (2) reinitiating antipsychotic treatment for tics occurring following discontinuation, or (3) using non-antipsychotic agents. It should be noted that symptoms were not always fully reversible and recurred at times., Conclusion: Tics can be a disturbing adverse effect of antipsychotics. Clinicians need to be particularly vigilant when initiating and modifying antipsychotic regimens.

Retrospective data were collected from 330 individuals who were treated at a tertiary care program for treatment-resistant psychosis between 1994 and 2010. The main objectives were to compare the use of antipsychotic monotherapy to polypharmacy and to characterize within-individual changes in treatment and symptomatology between admission and discharge. At admission, individuals who were prescribed only one antipsychotic were comparable to those who were prescribed at least two antipsychotics with regard to demographics and symptom severity. The use of psychotropic medications other than antipsychotics was also similar between the two groups. However, the magnitude of antipsychotic utilization was greater in individuals who were receiving antipsychotic polypharmacy. In addition, a greater proportion received excessive doses at admission. Similar findings were observed when the two antipsychotic prescribing practices were compared at discharge. Three important patterns were identified when investigating within-individual changes. First, fewer individuals were prescribed more than one antipsychotic at discharge. This was accompanied by a general decrease in the magnitude of antipsychotic utilization. Second, the number of individuals who were prescribed clozapine had increased by discharge. Most who were already prescribed clozapine at admission had their doses increased. Third, improvements in symptomatology were observed across all of the subscales included in the Positive and Negative Symptom Scale (PANSS); 57.9% of individuals experienced a relative reduction in total PANSS scores exceeding 20%. Based on these findings, it is possible to alleviate symptom severity while reducing antipsychotic utilization when patients are treated at a tertiary care program for treatment-resistant psychosis., Competing Interests: Dr. Honer has received consulting fees or sat on advisory boards for In Silico, Eli Lilly, Roche, Lundbeck, and Otsuka. Dr. Barr has received consulting fees or sat on advisory boards for Bristol-Myers Squibb, Eli Lilly, and Roche. Dr. Procyshyn has received speaking and advisory board fees from Janssen, Lundbeck, Otsuka, and Sunovion and was a member of speaker’s bureaus for AstraZeneca, Janssen, Lundbeck, and Otsuka. The other authors declare no potential competing interests. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Background: Antidepressants are one of the most prescribed classes of medications. A number of case reports have linked these drugs to extrapyramidal symptoms (EPSs), but no large epidemiologic study to date has examined this association. We sought to quantify the association of EPSs with different antidepressants by undertaking a large pharmacoepidemiologic study., Methods: A nested case-control study was conducted using a large health claims database in the United States from June 2006 to December 2015. Subjects with a diagnosis of primary Parkinson disease and those who received prescriptions of levodopa, ropinirole, pramipexole, domperidone, metoclopramide, entacapone, benztropine, selegiline, rasagiline, diphenhydramine, trihexyphenidyl, typical and atypical antipsychotics, and tricyclic antidepressants were excluded. Cases were followed to the first billing code for an extrapyramidal event or last date of enrollment in the cohort. For each case, 10 control subjects were matched by follow-up time, calendar time, and age through density-based sampling. Rate ratios were computed using conditional logistic regression adjusting for other covariates., Results: We identified 3,838 subjects with EPSs compared with 38,380 age-matched control subjects. Rate ratios with respect to EPSs were as follows: duloxetine, 5.68 (95% confidence interval [CI], 4.29-7.53); mirtazapine, 3.78 (95% CI, 1.71-8.32); citalopram, 3.47 (95% CI, 2.68-4.50); escitalopram, 3.23 (95% CI, 2.44-4.26); paroxetine, 3.07 (95% CI, 2.15-4.40); sertraline, 2.57 (95% CI, 2.02-3.28); venlafaxine, 2.37 (95% CI, 1.71-3.29); bupropion, 2.31 (95% CI, 1.67-3.21); and fluoxetine, 2.03 (95% CI, 1.48-2.78)., Conclusions: This observational study demonstrates a harmful association between the incidence of Parkinson disease or associated EPSs and use of the antidepressants duloxetine, mirtazapine, citalopram, escitalopram, paroxetine, sertraline, venlafaxine, bupropion, and fluoxetine.

The second generation antipsychotic drug risperidone is widely used in the field of child and adolescent psychiatry to treat conditions associated with disruptive behavior, aggression and irritability, such as autism spectrum disorders. While risperidone can provide symptomatic relief for many patients, there is considerable individual variability in the therapeutic response and side-effect profile of the medication. One well established biological factor that contributes to these individual differences is genetic variation in the cytochrome P450 enzyme 2D6. The 2D6 enzyme metabolizes risperidone and therefore affects drug levels and dosing. In the present review, we summarize the current literature on 2D6 variants and their effects on risperidone responses, specifically in children and adolescents. Relevant articles were identified through systematic review, and after irrelevant articles were discarded, ten studies were included in the review. Most prospective studies were well controlled, but often did not have a large enough sample size to make robust statements about rarer variants, including those categorized as ultra-rapid and poor metabolizers. Individual studies demonstrated a role for different genetic variants in risperidone drug efficacy, pharmacokinetics, hyperprolactinemia, weight gain, extrapyramidal symptoms and drug-drug interactions. Where studies overlapped in measurements, there was typically a consensus between results. These findings indicate that the value of 2D6 genotyping in the youth population treated with risperidone requires further study, in particular with the less common variants.

Background: Clozapine is the antipsychotic of choice for treatment-resistant schizophrenia and has minimal risk for extrapyramidal symptoms. Therapeutic benefits, however, are accompanied by a myriad of cardiometabolic side-effects. The specific reasons for clozapine's high propensity to cause adverse cardiometabolic events remain unknown, but it is believed that autonomic dysfunction may play a role in many of these. Objective: This systematic review summarizes the literature on autonomic dysfunction and related cardiovascular side effects associated with clozapine treatment. Method: A search of the EMBASE, MEDLINE, and EBM Cochrane databases was conducted using the search terms antipsychotic agents, antipsychotic drug * , antipsychotic * , schizophrenia, schizophren * , psychos * , psychotic * , mental ill * , mental disorder * , neuroleptic * , cardiovascular * , cardiovascular diseases, clozapine * , clozaril * , autonomic * , sympathetic * , catecholamine * , norepinephrine, noradrenaline, epinephrine, adrenaline. Results: The search yielded 37 studies that were reviewed, of which only 16 studies have used interventions to manage cardiovascular side effects. Side effects reported in the studies include myocarditis, orthostatic hypotension and tachycardia. These were attributed to sympathetic hyperactivity, decreased vagal contribution, blockade of cholinergic and adrenergic receptors, reduced heart rate variability and elevated catecholamines with clozapine use. Autonomic neuropathy was identified by monitoring blood pressure and heart rate changes in response to stimuli and by spectral analysis of heart rate variability. Metoprolol, lorazepam, atenolol, propranolol, amlodipine, vasopressin and norepinephrine infusion were used to treat tachycardia and fluctuations in blood pressure, yet results were limited to case reports. Conclusion: The results indicate there is a lack of clinical studies investigating autonomic dysfunction and a limited use of interventions to manage cardiovascular side effects associated with clozapine. As there is often no alternative treatment for refractory schizophrenia, the current review highlights the need for better designed studies, use of autonomic tests for prevention of cardiovascular disease and development of novel interventions for clozapine-induced side effects.

Studies show that individuals with schizophrenia have impaired cardiovascular fitness (i.e., low peak aerobic power (VO 2 peak)). It is speculated that antipsychotics with adverse cardiovascular and metabolic profiles, in particular clozapine, have a significant impact on VO 2 peak. In this cross-sectional study, we examined whether exposure to clozapine was associated with further reduced VO 2 peak compared with non-clozapine antipsychotics. Thirty participants with chronic schizophrenia or schizoaffective disorder were divided into clozapine and non-clozapine groups. Mean daily doses of antipsychotics were standardized to chlorpromazine equivalents and haloperidol equivalents for antagonism of alpha 1 - and alpha 2 -adrenergic receptors. Participants completed an incremental-to-maximal symptom-limited exercise test on a cycle ergometer for the assessment of VO 2 peak. The clozapine group demonstrated significantly lower VO 2 peak than the non-clozapine group. Haloperidol equivalents for alpha-adrenergic receptor antagonism, but not chlorpromazine equivalents, demonstrated significant inverse associations with VO 2 peak. The clozapine group had a significantly higher amount of antagonistic activity at alpha-adrenergic receptors than the non-clozapine group. In conclusion, exposure to clozapine was associated with further reduced cardiovascular fitness, which may be explained by the drug's greater antagonistic activity at alpha-adrenergic receptors. Cardiovascular fitness needs to be promoted in individuals treated with antipsychotics, particularly clozapine, to prevent the risk of cardiovascular disease and mortality., (Copyright © 2018 Elsevier B.V. All rights reserved.)