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Cross-sectional studies have shown that the polygenic risk score for schizophrenia (PRS SCZ ) may influence heterogeneity in cognitive performance although evidence from family-based longitudinal study is limited. This study aimed to identify trajectories of cognitive function and assess whether the PRS SCZ is associated with baseline cognitive performance and predicted six-year trajectories. We included 1119 patients with a schizophrenia spectrum disorder, and 1059 unaffected siblings and 586 unrelated controls who are eligible at baseline. Genotype data were collected at baseline, whereas clinical and sociodemographic data were collected at baseline, three and six years. Group-based trajectory modeling was applied on a weighted standardized composite score of general cognition to unravel cognitive subtypes and explore trajectories over time. We followed a standard procedure to calculate the polygenic risk score. A random-effects ordinal regression model was used to investigate the association between PRS SCZ and cognitive subtypes. Five cognitive subtypes with variable trajectories were found in patients, four in siblings and controls, and six in all combined samples. PRS SCZ significantly predicted poor cognitive trajectories in patients, siblings and all samples. After Bonferroni correction and adjustment for non-genetic factors, only the results in all combined sample remained significant. Cognitive impairment in schizophrenia is heterogeneous and may be linked with high PRS SCZ . Our finding confirmed at least in all combined samples the presence of genetic overlap between schizophrenia and cognitive function and can give insight into the mechanisms of cognitive deficits., Competing Interests: Declaration of competing interest None., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Many individuals with severe mental disorders have difficulties in vocational and social functioning, which are regarded the most important outcomes, together with clinical symptoms. To understand the underlying mechanisms, research is increasingly focused on factors influencing functional outcomes. One established association has been shown between cognition and community functioning with negative symptoms as a possible mediator. Although it has been shown that negative symptoms consist of two subdomains, thus far negative symptoms have been assessed as one unitary construct. This study considers for the first time subdomains of negative symptoms as putative mediators (expressive deficits, amotivation) of the association between cognition (neuro- and social cognition) and functional outcome (living situation, occupation, social functioning). We expected that specific subdomains of negative symptoms (e.g. amotivation) would mediate the effect of cognition on specific functional outcomes (e.g. social functioning) independently from illness duration. To assess this, we included two independent cohorts, consisting of participants with different illness duration. These two independent cohorts consisted of patients with a recent-onset psychotic disorder: PROGR-S (first time treated; N = 1129) and GROUP (illness duration preferably <5 years; N = 1200). Using linear regression, mediation analyses were performed with two cognition domains (neurocognition and social cognition) as predictors, negative symptoms (Expressive deficits and Amotivation as indexed with items from the Positive and Negative Syndrome Scale) as mediators and three measures of functional outcomes (living situation, occupation and social functioning) as outcome measures. The analyses were repeated with the same outcome measures three years later. Three main results were obtained. I) Both in the cross-sectional and longitudinal analyses, the associations of neurocognition (both cohorts) and social cognition (GROUP) with social functioning were mediated by amotivation. II) The association between cognition and living situation was mediated by Expressive deficits in one cohort (GROUP) but not in the cohort assessing first-episode psychosis (PROGR-S). III) The association between cognition and occupation was mediated by Amotivation in PROGR-S and by Expressive deficits in GROUP. CONCLUSION: The current results show a less robust mediating role for specific negative symptom domains regarding the associations of cognition with occupation and living situation that may depend on the duration of psychotic illness. However, Amotivation, mediates the association between cognition and social functioning, which holds true for patients experiencing a first-onset and patients with a longer illness duration alike. The results may have implications for the development of therapeutic approaches focusing on amotivation to improve social functioning. GENERAL SCIENTIFIC SUMMARY: This study stresses the importance of distinguishing subdomains of negative symptoms, cognition and functioning. Our results show that specific negative symptom dimensions mediate the effects of cognition on specific functional outcomes., Competing Interests: Declaration of competing interest AA received speakers fees from Lundbeck. All other authors declare that there are no conflicts of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Social amotivation is a core element of the negative symptoms of schizophrenia. However, it is still largely unknown which neural substrates underpin social amotivation in people with schizophrenia, though deficiencies in the mesocorticolimbic dopamine system have been proposed., Methods: We examined the association between social amotivation and substantia nigra/ventral tegmental area-seeded intrinsic connectivity in 84 people with schizophrenia using resting state functional magnetic resonance imaging., Results: Spontaneous fluctuations of midbrain dopaminergic regions were positively associated with striatal and prefrontal fluctuations in people with schizophrenia. Most importantly, social amotivation was negatively associated with functional connectivity between the midbrain's substantia nigra/ventral tegmental area and medial- and lateral prefrontal cortex, the temporoparietal junction, and dorsal and ventral striatum. These associations were observed independently of depressive and positive symptoms., Conclusions: Our findings suggest that social amotivation in people with schizophrenia is associated with altered intrinsic connectivity of mesocorticolimbic pathways linked to cognitive control and reward processing. Dysconnectivity of dopaminergic neuronal ensembles that are fundamental to approach behavior and motivation may help explain the lack of initiative social behavior in people with social amotivation., (Copyright © 2019. Published by Elsevier B.V.)

This exploratory study reports on the effects of Repetitive Transcranial Magnetic Stimulation (rTMS) on (prefrontal) brain activity changes during ambiguous emotional evaluation in patients with schizophrenia. Before and after randomly assigned treatment with active and sham rTMS, patients performed the Wall of Faces task during fMRI scanning. fMRI analysis showed that rTMS treatment resulted in reduced activation of striato-fronto-parietal brain areas, while activation increased compared to baseline after sham. Thus, prefrontal rTMS may normalize an increased brain response to ambiguous emotional stimuli, but future studies should confirm these findings., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: Patients with psychotic disorders are at risk of developing mental health and social problems, and physical disorders. To monitor and treat these problems when indicated, an annual routine outcome monitoring program, Pharmacotherapy Monitoring and Outcome Survey (PHAMOUS), was developed. This paper presents the background and content of PHAMOUS, implementation of PHAMOUS, characteristics of the patients screened in 2015, and the outcome of patients with three annual screenings between 2011 and 2015., Methods: PHAMOUS was implemented in four mental health institutions in the Northern Netherlands in 2006. During the PHAMOUS screening, patients are assessed on socio-demographics, psychiatric symptoms, medication, physical parameters, lifestyle, (psycho)social functioning and quality of life, using internationally validated instruments., Results: In 2015, 1955 patients with psychotic disorders were enrolled in the PHAMOUS screening. The majority (72%) was receiving mental healthcare for ten years or longer. A small group was hospitalized (10%) in the past year. Half of the patients were in symptomatic remission. Less than 10% had a paid job. More than half of the patients fulfilled the criteria for metabolic syndrome (54%). The subsample with three annual screenings from 2011 to 2015 (N = 1230) was stable, except the increasing prevalence of high glucose levels and satisfaction with social relationships (Cochran's Q = 16.33, p = .001 resp. Q = 14.79, p = .001)., Conclusion: The annual PHAMOUS screening enables to follow the mental, physical and social health problems of patients, which offers a good basis for shared-decision making with regard to updating the annual treatment plan, next to a wealth of data for scientific research., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: The longitudinal course of the negative symptoms subdomains social amotivation (SA) and expressive deficits (ED) remains largely unknown. We investigated i) the longitudinal course of SA and ED subdomain scores, ii) whether subgroups based on the course of SA and ED subdomain scores could be identified, iii) whether baseline SA and ED subdomain scores were related to functioning and quality of life six years later and iv) the longitudinal relationship between subgroups and outcomes., Methods: Measurements at baseline, three and six years from 1067 patients participating in the Genetic Risk and Outcome of Psychosis (GROUP) project were used. We applied mixed models analysis, regression analysis and trajectory analyses., Results: SA and ED subdomain scores decreased over time. Within both subdomains, four subgroups were identified: for both SA and ED a steady low course (±60%), increased (±15%) and decreased course (±15%). Within SA only, a higher level decreased course (±6%) and within ED only, a course with relatively stable high ED scores (±6%) was found. Lower symptom levels at baseline were related to better functioning (SA & ED) and quality of life (SA) at six years. Overall, low SA and low ED subgroups showed better outcomes than the other subgroups., Conclusion: In many patients the course of negative symptoms is unstable and related to the course of outcome. Patients who do show steady low negative symptom levels (60%) may complicate the interpretation of treatment evaluation studies, as they may average out possible effects in subgroups with fluctuating symptom levels., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Insight is impaired in most patients with psychosis and has been associated with poorer prognosis. The exact neural basis of impaired insight is still unknown, but it may involve disrupted prefrontal neural connectivity. Numerous studies have indeed found white matter (WM) abnormalities in psychosis. The association between prefrontal WM abnormalities and insight has not been studied yet by means of proton magnetic resonance spectroscopy ( 1 H-MRS). 1 H-MRS can be used to measure N-acetylaspartate (NAA), which is considered to be a marker of neuronal integrity. We measured insight with the Birchwood Insight Scale (BIS) as well as item G12 of the Positive and Negative Syndrome Scale (PANSS) in 88 patients with psychosis. Prefrontal WM concentrations of NAA and ratios of NAA to creatine (Cr) were assessed with 1 H-MRS. Nonparametric partial correlational analyses were conducted between NAA concentrations and insight controlling for illness duration, standardized antipsychotic dose, symptom scores, voxel grey matter content and voxel cerebrospinal fluid content. We found a significant correlation between reduced NAA/Cr ratios and poorer insight as measured with the BIS, which remained significant after additional correction for full width at half maximum, signal/noise and age. This is the first study reporting a relationship between lower prefrontal concentrations of a marker of neuronal integrity and impaired insight, providing further evidence that prefrontal pathology may play an important role in impaired insight in psychosis. This may be explained by the involvement of the prefrontal cortex in several executive and metacognitive functions, such as cognitive flexibility and perspective taking., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Cannabis use has been associated with favorable outcomes on metabolic risk factors. The cause of this relation is still unknown. In this study we investigated whether this effect is mediated by the AKT1 gene, as activation of the related enzyme by cannabis may cause metabolic changes. Six Single Nucleotide Polymorphisms (SNPs) of the AKT1 gene (rs1130214, rs1130233, rs2494732, rs2498784, rs3730358, and rs3803300) of patients with psychotic disorders (n=623) were related to Body Mass Index (BMI), levels of glycosylated hemoglobin (HBA1c) and total metabolic risk. Next, mediation analysis was performed with BMI as outcome, cannabis as predictor, and AKT1 as mediator. Cannabis use was inversely related to BMI but not with levels of HBA1c and total metabolic risk. Moreover, out of 6 AKT1 SNPs, rs2494732 was associated with cannabis use, but AKT1 did not mediate the effect of cannabis on BMI. In conclusion, cannabis use is likely to be associated with a lower BMI in patients with a psychotic disorder. Moreover, AKT1 risk alleles may increase the incidence of cannabis use in patients with a psychotic disorder, but AKT1 does not appear to mediate the effect of cannabis on BMI., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Prefrontal cortical dysfunction is frequently reported in schizophrenia and is thought to underlie negative symptoms of schizophrenia. Repetitive Transcranial Magnetic Stimulation (rTMS) can modulate neuronal activity and has been shown to improve negative symptoms in patients with schizophrenia, but the underlying neural mechanism is unknown., Objective: To examine whether 3weeks of 10Hz rTMS treatment of the bilateral dorsolateral prefrontal cortex (DLPFC) would improve frontal brain activation in patients with negative symptoms of schizophrenia, as measured by functional magnetic resonance imaging (fMRI) during the Tower of London (ToL) task., Methods: 24 patients with the diagnosis of schizophrenia with moderate to severe negative symptoms (Positive and Negative Syndrome Scale (PANSS) negative subscale≥15) participated. Patients were randomized to a 3-week (15day) course of active or sham rTMS. All patients performed the ToL task during fMRI scanning both pre-treatment and post-treatment. Differences in brain activation between the two groups were compared non-parametrically., Results: After rTMS treatment, brain activity in the active group increased in the right DLPFC and the right medial frontal gyrus as compared to the sham group. In addition, the groups significantly differed with regard to activation change in the left posterior cingulate, with decreased activation in the active and increased activation in the sham group., Conclusions: Treatment with rTMS over the DLPFC may have the potential for increasing task-related activation in frontal areas in patients with schizophrenia. Effects of different rTMS parameters and fMRI tasks targeting relevant brain circuitry deserve further investigation., Trial Registration: Nederlands Trial Register, registration number: NTR1261., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Patients with schizophrenia often suffer from apathy: a quantitative reduction of voluntary, goal-directed behaviors that impairs daily functioning. We hypothesized that schizophrenia patients with high levels of apathy would show decreased activation in brain regions involved in planning and goal-directed behavior. Patients with schizophrenia or psychotic spectrum disorder (n=47) and healthy controls (n=20) performed the Tower of London (ToL) task during fMRI scanning using arterial spin labeling. To investigate the relationship between apathy and planning in patients, a proxy measure of apathy based on the Positive and Negative syndrome Scale was regressed against the task-related brain activation. Brain activation was also compared between patients and healthy controls. Higher levels of apathy were associated with less task-related activation within the inferior parietal lobule precuneus and thalamus. Compared to controls, patients showed lower activation in lateral prefrontal regions, parietal and motor areas, and a higher activation of medial frontal areas. Apathy was related to abnormal activation in thalamus and parietal regions during the ToL task. This supports the hypothesis that impaired function of brain regions involved in planning and goal-directed behavior may underlie apathy in schizophrenia. Moreover, impaired lateral prefrontal activation in schizophrenia patients compared to controls is consistent with the hypofrontality model of schizophrenia. In contrast, stronger medial frontal activation in patients may be related to increased effort to perform a task with conflicting task solutions., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Monitoring patients' experiences with antipsychotics may help to improve medication adherence and outcome. We aimed to develop a shorter version of a comprehensive 74-item self-report questionnaire suitable for routine monitoring of desired and undesired effects of antipsychotics., Methods: Included were patients with psychotic disorders from seven mental health care organizations in The Netherlands, using antipsychotic medication, who completed the Subjects' Response to Antipsychotics (SRA-74). Exploratory factor analysis (EFA) and similarity analysis based on mutual information were used to identify the latent factor structure of the SRA. Items were reduced according to their metric properties and clinical relevance upon consensus by an expert panel, using a Delphi procedure of three rounds. We determined the internal consistency of the shorter version using Cronbach's alpha., Results: SRA data of N=1478 patients (mean age of 40 years, 31% females) were eligible for analysis. EFA extracted thirteen factors from the SRA-74, including four factors for desired effects (e.g. recovery of psychosis, cognition and social functioning) and nine factors for undesired effects (e.g. weight gain, flattened affect and increased sleep). Based on this solution 12 items were eliminated for statistical reasons. The expert panel eliminated another 28 items with redundant content, resulting in a 34-item version. The SRA-34 includes 10 desired and 24 clinically relevant undesired effects. Both the subscales for desired and undesired effects have a Cronbach's alpha coefficient of 0.82., Conclusions: The SRA-34 can be used to evaluate desired and undesired effects of antipsychotics in routine clinical practice and research., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Brain circuits involved in language processing have been suggested to be compromised in patients with schizophrenia. This does not only include regions subserving language production and perception, but also auditory processing and attention. We investigated resting state network connectivity of auditory, language and attention networks of patients with schizophrenia and hypothesized that patients would show reduced connectivity. Patients with schizophrenia (n = 45) and healthy controls (n = 30) underwent a resting state fMRI scan. Independent components analysis was used to identify networks of the auditory cortex, left inferior frontal language regions and the anterior cingulate region, associated with attention. The time courses of the components where correlated with each other, the correlations were transformed by a Fisher's Z transformation, and compared between groups. In patients with schizophrenia, we observed decreased connectivity between the auditory and language networks. Conversely, patients showed increased connectivity between the attention and language network compared to controls. There was no relationship with severity of symptoms such as auditory hallucinations. The decreased connectivity between auditory and language processing areas observed in schizophrenia patients is consistent with earlier research and may underlie language processing difficulties. Altered anterior cingulate connectivity in patients may be a correlate of habitual suppression of unintended speech, or of excessive attention to internally generated speech. This altered connectivity pattern appears to be present independent of symptom severity, and may be suggestive of a trait, rather than a state characteristic., (Copyright © 2011 Elsevier B.V. All rights reserved.)