Search

BackgroundCannabis is increasingly used both medically and recreationally. With widespread use, there is growing concern about how to identify cannabis-impaired drivers.MethodsA placebo-controlled randomized double-blinded protocol was conducted to study the effects of cannabis on driving performance. One hundred ninety-one participants were randomized to smoke ad libitum a cannabis cigarette containing placebo or delta-9-tetrahydrocannabinol (THC) (5.9% or 13.4%). Blood, oral fluid (OF), and breath samples were collected along with longitudinal driving performance on a simulator (standard deviation of lateral position [SDLP] and car following [coherence]) over a 5-hour period. Law enforcement officers performed field sobriety tests (FSTs) to determine if participants were impaired.ResultsThere was no relationship between THC concentrations measured in blood, OF, or breath and SDLP or coherence at any of the timepoints studied (P > 0.05). FSTs were significant (P < 0.05) for classifying participants into the THC group vs the placebo group up to 188 minutes after smoking. Seventy-one minutes after smoking, FSTs classified 81% of the participants who received active drug as being impaired. However, 49% of participants who smoked placebo (controls) were also deemed impaired at this same timepoint. Combining a 2 ng/mL THC cutoff in OF with positive findings on FSTs reduced the number of controls classified as impaired to zero, 86 minutes after smoking the placebo.ConclusionsRequiring a positive toxicology result in addition to the FST observations substantially improved the classification accuracy regarding possible driving under the influence of THC by decreasing the percentage of controls classified as impaired.

Background: Accurate drug use identification through subjective self-report and toxicological biosample (hair) analysis are necessary to determine substance use sequelae in youth. Yet consistency between self-reported substance use and robust, toxicological analysis in a large sample of youth is understudied.Objectives: We aim to assess concordance between self-reported substance use and hair toxicological analysis in community-based adolescents.Methods: Hair results by LC-MS/MS and GC-MS/MS and self-reported past-year substance use from an Adolescent Brain Cognitive Development (ABCD) Study subsample (N = 1,390; ages 9-13; 48% female) were compared. The participants were selected for hair selection through two methods: high scores on a substance risk algorithm selected 93%; 7% were low-risk, randomly selected participants. Kappa coefficients the examined concordance between self-report and hair results.Results: 10% of youth self-reported any past-year substance use (e.g. alcohol, cannabis, nicotine, and opiates), while a mostly non-overlapping 10% had hair results indicating recent substance use (cannabis, alcohol, non-prescription amphetamines, cocaine, nicotine, opiates, and fentanyl). In randomly selected low-risk cases, 7% were confirmed positive in hair. Combining methods, 19% of the sample self-reported substance use and/or had a positive hair sample. Kappa coefficient of concordance between self-report and hair results was low (kappa = 0.07; p = .007).Conclusions: Hair toxicology identified substance use in high-risk and low-risk ABCD cohort subsamples. Given low concordance between hair results and self-report, reliance on either method alone would incorrectly categorize 9% as non-users. Multiple methods for characterizing substance use history in youth improves accuracy. Larger representative samples are needed to assess the prevalence of substance use in youth.

Passive aerosol exposure to Δ9-tetrahydrocannabinol (THC) in laboratory animals results in faster onset of action and less extensive liver metabolism compared to most other administration routes and might thus provide an ecologically relevant model of human cannabis inhalation. Previous studies have, however, overlooked the possibility that rodents, as obligate nose breathers, may accumulate aerosolized THC in the nasal cavity, from where the drug might directly diffuse to the brain. To test this, we administered THC (ten 5-s puffs of 100 mg/mL of THC) to adolescent (31-day-old) Sprague-Dawley rats of both sexes. We used liquid chromatography/tandem mass spectrometry to quantify the drug and its first-pass metabolites - 11-hydroxy-Δ9-THC (11-OH-THC) and 11-nor-9-carboxy-Δ9-THC (11-COOH-THC) - in nasal mucosa, lungs, plasma, and brain (olfactory bulb and cerebellum) at various time points after exposure. Apparent maximal THC concentration and area under the curve were ∼5 times higher in nasal mucosa than in lungs and 50-80 times higher than in plasma. Concentrations of 11-OH-THC were also greater in nasal mucosa and lungs than other tissues, whereas 11-COOH-THC was consistently undetectable. Experiments with microsomal preparations confirmed local metabolism of THC into 11-OH-THC (not 11-COOH-THC) in nasal mucosa and lungs. Finally, whole-body exposure to THC deposited substantial amounts of THC (∼150 mg/g) on fur but suppressed post-exposure grooming in rats of both sexes. The results indicate that THC absorption and metabolism in nasal mucosa and lungs, but probably not gastrointestinal tract, contribute to the pharmacological effects of aerosolized THC in male and female rats.

AimA key aim of the Adolescent Brain Cognitive Development℠ (ABCD) Study is to document substance use onset, patterns, and sequelae across adolescent development. However, substance use misreporting can obscure accurate drug use characterization. Hair toxicology provides objective historical substance use data but is rarely used in studies of youth. Here, we compare objective hair toxicology results with self-reported substance use in high-risk youth.MethodsA literature-based substance use risk algorithm prioritized 696 ABCD Study® hair samples from 677 participants for analysis at baseline, and 1 and 2-year follow-ups (spanning ages 9-13). Chi-square and t-tests assessed differences between participants' demographics, positive and negative hair tests, risk-for-use algorithm scores, and self-reported substance use.ResultsHair testing confirmed that 17% of at-risk 9-13 year-olds hair samples had evidence of past 3-month use of one (n = 97), two (n = 14), three (n = 2), or four (n = 2) drug classes. After considering prescribed medication and self-reported substance use, 10% had a positive test indicating substance use that was not reported. Participants with any positive hair result reported less sipping of alcohol (p

ImportanceExpanding cannabis medicalization and legalization increases the urgency to understand the factors associated with acute driving impairment.ObjectiveTo determine, in a large sample of regular cannabis users, the magnitude and time course of driving impairment produced by smoked cannabis of different Δ9-tetrahydrocannabinol (THC) content, the effects of use history, and concordance between perceived impairment and observed performance.Design, setting, and participantsThis double-blind, placebo-controlled parallel randomized clinical trial took place from February 2017 to June 2019 at the Center for Medicinal Cannabis Research, University of California San Diego. Cannabis users were recruited for this study, and analysis took place between April 2020 and September 2021.InterventionsPlacebo or 5.9% or 13.4% THC cannabis smoked ad libitum.Main outcomes and measuresThe primary end point was the Composite Drive Score (CDS), which comprised key driving simulator variables, assessed prior to smoking and at multiple time points postsmoking. Additional measures included self-perceptions of driving impairment and cannabis use history.ResultsOf 191 cannabis users, 118 (61.8%) were male, the mean (SD) age was 29.9 (8.3) years, and the mean (SD) days of use in the past month was 16.7 (9.8). Participants were randomized to the placebo group (63 [33.0%]), 5.9% THC (66 [34.6%]), and 13.4% THC (62 [32.5%]). Compared with placebo, the THC group significantly declined on the Composite Drive Score at 30 minutes (Cohen d = 0.59 [95% CI, 0.28-0.90]; P

ObjectiveVerbal memory deficits are linked to cannabis use. However, self-reported episodic use does not allow for assessment of variance from other factors (e.g., cannabis potency, route of consumption) that are important for assessing brain-behavior relationships. Further, co-occurring nicotine use may moderate the influence of cannabis on cognition. Here we utilized objective urinary measurements to assess the relationship between metabolites of cannabis, 11-nor-9-carboxy-∆9-tetrahydrocannabinol (THCCOOH), and nicotine (cotinine) on verbal memory in young adults.MethodAdolescents and young adults (n = 103) aged 16-22 completed urinary drug testing and verbal memory assessment (RAVLT). Linear regressions examined the influence of THCCOOH and cotinine quantitative concentrations, and their interaction, on RAVLT scores, controlling for demographics and alcohol. Cannabis intake frequency was also investigated. Secondary analyses examined whether past month or recency of use related to performance, while controlling for THCCOOH and cotinine concentrations.ResultsTHCCOOH concentration related to both poorer total learning and long delay recall. Cotinine concentration related to poorer short delay recall. Higher frequency cannabis use status was associated with poorer initial learning and poorer short delay. When comparing to self-report, THCCOOH and cotinine concentrations were negatively related to learning and memory performance, while self-report was not.ConclusionsResults confirm the negative relationship between verbal memory and cannabis use, extending findings with objective urinary THCCOOH, and cotinine concentration measurements. No moderating relationship with nicotine was found, though cotinine concentration independently associated with negative short delay performance. Findings support the use of both urinary and self-report metrics as complementary methods in substance use research.

Δ9-tetrahydrocannabinol (THC) is the intoxicating constituent of cannabis and is responsible for the drug's reinforcing effects. Retrospective human studies suggest that cannabis use during adolescence is linked to long-term negative psychological outcomes, but in such studies it is difficult to distinguish the effects of THC from those of coexisting factors. Therefore, translationally relevant animal models are required to properly investigate THC effects in adolescents. However, though the relevance of these studies depends upon human-relevant dosing, surprisingly little is known about THC pharmacology and its effects on behavior and brain activity in adolescent rodents-especially in females. Here, we conducted a systematic investigation of THC pharmacokinetics, metabolism and distribution in blood and brain, and of THC effects upon behavior and neural activity in adolescent Long Evans rats of both sexes. We administered THC during an early-middle adolescent window (postnatal days 27-45) in which the brain may be particularly sensitive to developmental perturbation by THC. We determined the pharmacokinetic profile of THC and its main first-pass metabolites (11-hydroxy-THC and 11-nor-9-carboxy-THC) in blood and brain following acute injection (0.5 or 5 mg/kg, intraperitoneal). We also evaluated THC effects on behavioral assays of anxiety, locomotion, and place conditioning, as well as c-Fos expression in 14 brain regions. Confirming previous work, we find marked sex differences in THC metabolism, including a female-specific elevation in the bioactive metabolite 11-hydroxy-THC. Furthermore, we find dose-dependent and sex-dependent effects on behavior, neural activity, and functional connectivity across multiple nodes of brain stress and reward networks. Our findings are relevant for interpreting results of rat adolescent THC exposure studies, and may lend new insights into how THC impacts the brain in a sex-dependent manner.

AimTo examine individual variability between perceived physical features and hormones of pubertal maturation in 9-10-year-old children as a function of sociodemographic characteristics.MethodsCross-sectional metrics of puberty were utilized from the baseline assessment of the Adolescent Brain Cognitive Development (ABCD) Study-a multi-site sample of 9-10 year-olds (n = 11,875)-and included perceived physical features via the pubertal development scale (PDS) and child salivary hormone levels (dehydroepiandrosterone and testosterone in all, and estradiol in females). Multi-level models examined the relationships among sociodemographic measures, physical features, and hormone levels. A group factor analysis (GFA) was implemented to extract latent variables of pubertal maturation that integrated both measures of perceived physical features and hormone levels.ResultsPDS summary scores indicated more males (70%) than females (31%) were prepubertal. Perceived physical features and hormone levels were significantly associated with child's weight status and income, such that more mature scores were observed among children that were overweight/obese or from households with low-income. Results from the GFA identified two latent factors that described individual differences in pubertal maturation among both females and males, with factor 1 driven by higher hormone levels, and factor 2 driven by perceived physical maturation. The correspondence between latent factor 1 scores (hormones) and latent factor 2 scores (perceived physical maturation) revealed synchronous and asynchronous relationships between hormones and concomitant physical features in this large young adolescent sample.ConclusionsSociodemographic measures were associated with both objective hormone and self-report physical measures of pubertal maturation in a large, diverse sample of 9-10 year-olds. The latent variables of pubertal maturation described a complex interplay between perceived physical changes and hormone levels that hallmark sexual maturation, which future studies can examine in relation to trajectories of brain maturation, risk/resilience to substance use, and other mental health outcomes.

Background and objectivesThe effects of in utero methamphetamine exposure on behavioral problems in school-aged children are unclear. Our objective for this study was to evaluate behavior problems in children at aged 3, 5, and 7.5 years who were prenatally exposed to methamphetamine.MethodsSubjects were enrolled in the Infant Development, Environment, and Lifestyle study, a longitudinal prospective study of prenatal methamphetamine exposure and child outcomes. Exposed and comparison groups were matched on birth weight, race, education, and health insurance.  At ages 3, 5, and 7.5 years, 339 children (171 exposed) were assessed for behavior problems by using the Child Behavior Checklist. Generalized estimating equations were used to determine the effects of prenatal methamphetamine exposure, age, and the interaction of exposure and age on behavior problems. Caregiver psychological symptoms were assessed by using the Brief Symptom Inventory.ResultsAnalyses adjusted for covariates revealed that relative to age 3, children at 5 years had less externalizing and aggressive behavior and more internalizing behavior, somatic complaints, and withdrawn behavior.  By age 7.5, aggressive behavior continued to decrease, attention problems increased and withdrawn behavior decreased. There were no main effects for methamphetamine exposure and no interactions of exposure and age.  Caregiver psychological symptoms predicted all behavior problems and the quality of the home predicted externalizing problems and externalizing syndrome scores.ConclusionsBehavioral effects longitudinally from ages 3 to 7.5 years were not associated with prenatal methamphetamine exposure, whereas caregiver psychological symptoms and the quality of the home were predictors of behavior problems.

We investigated the pharmacokinetic properties of Δ9-tetrahydrocannabinol (Δ9-THC), the main psychoactive constituent of cannabis, in adolescent and adult male mice. The drug was administered at logarithmically ascending doses (0.5, 1.6, and 5 mg/kg, i.p.) to pubertal adolescent (37-day-old) and adult (70-day-old) mice. Δ9-THC and its first-pass metabolites-11-hydroxy-Δ9-THC and 11-nor-9-carboxy-Δ9-THC (11-COOH-THC)-were quantified in plasma, brain, and white adipose tissue (WAT) using a validated isotope-dilution liquid chromatography/tandem mass spectrometry assay. Δ9-THC (5 mg/kg) reached 50% higher circulating concentration in adolescent mice than in adult mice. A similar age-dependent difference was observed in WAT. Conversely, 40%-60% lower brain concentrations and brain-to-plasma ratios for Δ9-THC and 50%-70% higher brain concentrations for Δ9-THC metabolites were measured in adolescent animals relative to adult animals. Liver microsomes from adolescent mice converted Δ9-THC into 11-COOH-THC twice as fast as adult microsomes. Moreover, the brains of adolescent mice contained higher mRNA levels of the multidrug transporter breast cancer resistance protein, which may extrude Δ9-THC from the brain, and higher mRNA levels of claudin-5, a protein that contributes to blood-brain barrier integrity. Finally, administration of Δ9-THC (5 mg/kg) reduced spontaneous locomotor activity in adult, but not adolescent, animals. The results reveal the existence of multiple differences in the distribution and metabolism of Δ9-THC between adolescent and adult male mice, which might influence the pharmacological response to the drug. SIGNIFICANCE STATEMENT: Animal studies suggest that adolescent exposure to Δ9-tetrahydrocannabinol (Δ9-THC), the intoxicating constituent of cannabis, causes persistent changes in brain function. These studies generally overlook the impact that age-dependent changes in the distribution and metabolism of the drug might exert on its pharmacological effects. This report provides a comparative analysis of the pharmacokinetic properties of Δ9-THC in adolescent and adult male mice and outlines multiple functionally significant dissimilarities in the distribution and metabolism of Δ9-THC between these two age groups.

BACKGROUND: The study examined the association between prenatal tobacco or co-exposure to tobacco and cannabis and childrens cortisol reactivity at kindergarten age and the role of child sex, maternal negative mood (depression/perceived stress), and parenting behavior during play interactions as moderators of this association. METHODS: The sample was 238 mother-child dyads (67 tobacco users, 83 co-users of tobacco and cannabis, and 88 non-users). Data used were obtained from pregnancy assessments and six postnatal assessments at 2, 9, 16, 24, and 36 months and kindergarten age. Infant cortisol was measured in response to two laboratory stress paradigms. RESULTS: Co-exposed children had a significantly greater decrease from pre-stressor to post-stressor and overall lower cortisol response compared with non-exposed children. This association was moderated by maternal harshness during play interactions across early childhood. Co-exposed children had flatter cortisol responses regardless of the mothers level of harshness or stress/depression. However, non-exposed children who experienced low harshness had the normative cortisol peak 20 min post-stressor, while non-exposed children with high maternal harshness had a flatter cortisol pattern. Similarly, non-exposed children with more depressed/stressed mothers had higher pre-stressor cortisol levels, while those who experienced low maternal depression/stress had lower pre-stressor cortisol but peaked post-stress. CONCLUSIONS: Results suggest that prenatal polysubstance exposure is associated with greater risk for lower cortisol response in children and highlight the role of parenting behavior for non-exposed but not the co-exposed children.

BackgroundThe study examined the association between prenatal tobacco or co-exposure to tobacco and cannabis and children's cortisol reactivity at kindergarten age and the role of child sex, maternal negative mood (depression/perceived stress), and parenting behavior during play interactions as moderators of this association.MethodsThe sample was 238 mother-child dyads (67 tobacco users, 83 co-users of tobacco and cannabis, and 88 non-users). Data used were obtained from pregnancy assessments and six postnatal assessments at 2, 9, 16, 24, and 36 months and kindergarten age. Infant cortisol was measured in response to two laboratory stress paradigms.ResultsCo-exposed children had a significantly greater decrease from pre-stressor to post-stressor and overall lower cortisol response compared with non-exposed children. This association was moderated by maternal harshness during play interactions across early childhood. Co-exposed children had flatter cortisol responses regardless of the mother's level of harshness or stress/depression. However, non-exposed children who experienced low harshness had the normative cortisol peak 20 min post-stressor, while non-exposed children with high maternal harshness had a flatter cortisol pattern. Similarly, non-exposed children with more depressed/stressed mothers had higher pre-stressor cortisol levels, while those who experienced low maternal depression/stress had lower pre-stressor cortisol but peaked post-stress.ConclusionsResults suggest that prenatal polysubstance exposure is associated with greater risk for lower cortisol response in children and highlight the role of parenting behavior for non-exposed but not the co-exposed children.

Background The widespread availability of cannabis raises concerns regarding its effect on driving performance and operation of complex equipment. Currently, there are no established safe driving limits regarding ∆9-tetrahydrocannabinol (THC) concentrations in blood or breath. Daily cannabis users build up a large body burden of THC with residual excretion for days or weeks after the start of abstinence. Therefore, it is critical to have a sensitive and specific analytical assay that quantifies THC, the main psychoactive component of cannabis, and multiple metabolites to improve interpretation of cannabinoids in blood; some analytes may indicate recent use. Methods A liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed to quantify THC, cannabinol (CBN), cannabidiol (CBD), 11-hydroxy-THC (11-OH-THC), (±)-11-nor-9-carboxy-Δ9-THC (THCCOOH), (+)-11-nor-Δ9-THC-9-carboxylic acid glucuronide (THCCOOH-gluc), cannabigerol (CBG), and tetrahydrocannabivarin (THCV) in whole blood (WB). WB samples were prepared by solid-phase extraction (SPE) and quantified by LC-MS/MS. A rapid and simple method involving methanol elution of THC in breath collected in SensAbues® devices was optimized. Results Lower limits of quantification ranged from 0.5 to 2 μg/L in WB. An LLOQ of 80 pg/pad was achieved for THC concentrations in breath. Calibration curves were linear (R2>0.995) with calibrator concentrations within ±15% of their target and quality control (QC) bias and imprecision ≤15%. No major matrix effects or drug interferences were observed. Conclusions The methods were robust and adequately quantified cannabinoids in biological blood and breath samples. These methods will be used to identify cannabinoid concentrations in an upcoming study of the effects of cannabis on driving.

AimTo examine individual variability between perceived physical features and hormones of pubertal maturation in 9-10-year-old children as a function of sociodemographic characteristics.MethodsCross-sectional metrics of puberty were utilized from the baseline assessment of the Adolescent Brain Cognitive Development (ABCD) Study-a multi-site sample of 9-10 year-olds (n = 11,875)-and included perceived physical features via the pubertal development scale (PDS) and child salivary hormone levels (dehydroepiandrosterone and testosterone in all, and estradiol in females). Multi-level models examined the relationships among sociodemographic measures, physical features, and hormone levels. A group factor analysis (GFA) was implemented to extract latent variables of pubertal maturation that integrated both measures of perceived physical features and hormone levels.ResultsPDS summary scores indicated more males (70%) than females (31%) were prepubertal. Perceived physical features and hormone levels were significantly associated with child's weight status and income, such that more mature scores were observed among children that were overweight/obese or from households with low-income. Results from the GFA identified two latent factors that described individual differences in pubertal maturation among both females and males, with factor 1 driven by higher hormone levels, and factor 2 driven by perceived physical maturation. The correspondence between latent factor 1 scores (hormones) and latent factor 2 scores (perceived physical maturation) revealed synchronous and asynchronous relationships between hormones and concomitant physical features in this large young adolescent sample.ConclusionsSociodemographic measures were associated with both objective hormone and self-report physical measures of pubertal maturation in a large, diverse sample of 9-10 year-olds. The latent variables of pubertal maturation described a complex interplay between perceived physical changes and hormone levels that hallmark sexual maturation, which future studies can examine in relation to trajectories of brain maturation, risk/resilience to substance use, and other mental health outcomes.

When faced with increasing drug‐related deaths and decline in practicing forensic pathologists, the need to quickly identify toxicology‐related deaths is evident in order to appropriately triage cases and expedite turnaround times. Lateral flow immunoassays conducted pre‐autopsy offer quick urine drug screen (UDS) results in minutes and are used to inform the need for autopsy. Over 1000 medicolegal cases were reviewed to compare UDS results to laboratory enzyme‐linked immunosorbent assay (ELISA) blood results to evaluate how well autopsy UDS predicted laboratory findings. Mass spectral analysis was performed on ELISA‐positive specimens and these data were used to investigate UDS false‐negative (FN) results when possible. Five different UDS devices (STAT One Step Drug of Abuse dip card and cassette, Premiere Biotech multi‐drug and fentanyl dip cards and ATTEST 6‐acetylmorphine (6‐AM) dip card) were tested encompassing 11 drug classes: 6‐AM, amphetamine/methamphetamine, benzodiazepines, benzoylecgonine, fentanyl, methadone, opioids, phencyclidine, and delta‐9‐tetrahydrocannabinol. Sensitivity, specificity, efficiency, and positive and negative predictive values >80% indicated that UDS was useful for predicting cases involving benzoylecgonine, methadone, methamphetamine, and phencyclidine. UDS was unreliable in predicting amphetamine, benzodiazepines, fentanyl, and opiates‐related cases due to a high percentage of FN (up to 11.2%, 8.0%, 12.4%, and 5.5%, respectively) when compared to ELISA blood results. For the later analytes, sensitivities were as low as 57.5%, 60.0%, 72.2%, and 66.7%, respectively. Overall results support that UDS cannot replace laboratory testing. Because UDS is subject to false‐positive and FN results users must understand the limitations of using UDS for triage or decision‐making purposes. [ABSTRACT FROM AUTHOR]

In recent years, potential therapeutic applications of several different cannabinoids, such as Δ9-tetrahydrocannabinol (Δ9-THC), its isomer Δ8-THC and Δ9-tetrahydrocannabivarin (Δ9-THCV), have been investigated. Nevertheless, to establish dose–effect relationship and to gain knowledge of their pharmacokinetics and metabolism, sensitive and specific analytical assays are needed to measure these compounds in patients. For this reason, we developed and validated an online extraction high-performance liquid/liquid chromatography–tandem mass spectrometry (LC/LC–MS-MS) method for the simultaneous quantification of 13 cannabinoids and metabolites including the Δ8 and Δ9 isomers of THC, THCV and those of their major metabolites in human plasma. Plasma was fortified with cannabinoids at varying concentrations within the working range of the respective compound and 200 µL was extracted using a simple one-step protein precipitation procedure. The extracts were analyzed using online trapping LC/LC–atmospheric pressure chemical ionization–MS-MS running in the positive multiple reaction monitoring mode. The lower limit of quantification ranged from 0.5 to 2.5 ng/mL, and the upper limit of quantification was 400 ng/mL for all analytes. Inter-day analytical accuracy and imprecision ranged from 82.9% to 109% and 4.3% to 20.3% (coefficient of variance), respectively. Of 534 plasma samples following controlled oral administration of Δ8-THCV, 236 were positive for Δ8-THCV (median; interquartile ranges: 3.5 ng/mL; 1.8–11.9 ng/mL), 383 for the major metabolite (−)-11-nor-9-carboxy-Δ8-tetrahydrocannabivarin (Δ8-THCV-COOH) (95.4 ng/mL; 20.7–328 ng/mL), 260 for (−)-11-nor-9-carboxy-Δ9-tetrahydrocannabivarin (Δ9-THCV-COOH) (5.8 ng/mL; 2.5–16.1 ng/mL), 157 for (−)-11-hydroxy-Δ8-tetrahydrocannabivarin (11-OH-Δ8-THCV) (1.7 ng/mL; 1.0–3.7 ng/mL), 49 for Δ8-THC-COOH (1.7 ng/mL; 1.4–2.3 ng/mL) and 42 for Δ9-THCV (1.3 ng/mL; 0.8–1.6 ng/mL). We developed and validated the first LC/LC–MS-MS assay for the specific quantification of Δ8-THC, Δ9-THC and THCV isomers and their respective metabolites in human plasma. Δ8-THCV-COOH, 11-hydroxy-Δ8-THCV and Δ9-THCV-COOH were the major Δ8-THCV metabolites in human plasma after oral administration of 98.6% pure Δ8-THCV. [ABSTRACT FROM AUTHOR]

RationaleAdvancing marijuana prevention and intervention efforts are important given the decreasing perception of harm among adolescents and increasing marijuana legalization.ObjectivesThis study evaluates how a monitored abstinence protocol may contribute to emotional functioning and changes in marijuana problems that can enhance successful outcomes for non-treatment-seeking adolescent marijuana users.MethodsAdolescent marijuana users (n = 26) and demographically matched controls (n = 30) completed 28 days of monitored abstinence confirmed by biweekly urine toxicology. Participants were given measures of emotional functioning, marijuana use symptoms, and reward sensitivity during monitored abstinence.ResultsAll participants (n = 56) completed the protocol, and 69% of marijuana users (n = 18 of 26) were confirmed abstinent for 28 days, with all users showing decreasing marijuana use. Reductions in subsyndromal depression, positive marijuana use expectancies, and poor sleep quality were observed by the end of the monitored abstinence period (n = 26, p values

Cortical thickness abnormalities have been identified in youth using both alcohol and marijuana. However, limited studies have followed individuals pre- and post initiation of alcohol and marijuana use to help identify to what extent discrepancies in structural brain integrity are pre-existing or substance-related. Adolescents (N=69) were followed from ages 13 (pre-initiation of substance use, baseline) to ages 19 (post-initiation, follow-up). Three subgroups were identified, participants that initiated alcohol use (ALC, n=23, >20 alcohol use episodes), those that initiated both alcohol and marijuana use (ALC+MJ, n=23, >50 marijuana use episodes) and individuals that did not initiate either substance regularly by follow-up (CON, n=23, ALC+MJ). Minimal neurocognitive differences were observed in this sample. Findings suggest pre-existing neural differences prior to marijuana use may contribute to initiation of use and observed neural outcomes. Marijuana use may also interfere with thinning trajectories that contribute to morphological differences in young adulthood that are often observed in cross-sectional studies of heavy marijuana users.

Although kratom use has been part of life for centuries in Southeast Asia, the availability and use of kratom in the United States (US) increased substantially since the early 2000s when there was little information on kratom pharmacology, use patterns, and effects, all critical to guiding regulation and policy. Here we provide a synthesis of research with several hundred English-language papers published in the past 5 years drawing from basic research, epidemiological and surveillance data, and recent clinical research. This review of available literature aims to provide an integrated update regarding our current understanding of kratom's benefits, risks, pharmacology, and epidemiology, which may inform United States-based kratom regulation. Recent surveillance indicates there are likely several million past-year kratom consumers, though estimates vary widely. Even without precise prevalence data, kratom use is no longer a niche, with millions of United States adults using it for myriad reasons. Despite its botanical origins in the coffee tree family and its polypharmacy, kratom is popularly characterized as an opioid with presumed opioid-system-based risks for addiction or overdose. Neuropharmacology, toxicology, and epidemiology studies show that kratom is more accurately characterized as a substance with diverse and complex pharmacology. Taken together the work reviewed here provides a foundation for future scientific studies, as well as a guide for ongoing efforts to regulate kratom. This work also informs much-needed federal oversight, including by the United States Food and Drug Administration. We conclude with recommendations for kratom regulation and research priorities needed to address current policy and knowledge gaps around this increasingly used botanical product. [ABSTRACT FROM AUTHOR]

Cortical thickness abnormalities have been identified in youth using both alcohol and marijuana. However, limited studies have followed individuals pre- and post initiation of alcohol and marijuana use to help identify to what extent discrepancies in structural brain integrity are pre-existing or substance-related. Adolescents (N=69) were followed from ages 13 (pre-initiation of substance use, baseline) to ages 19 (post-initiation, follow-up). Three subgroups were identified, participants that initiated alcohol use (ALC, n=23, >20 alcohol use episodes), those that initiated both alcohol and marijuana use (ALC+MJ, n=23, >50 marijuana use episodes) and individuals that did not initiate either substance regularly by follow-up (CON, n=23, ALC+MJ). Minimal neurocognitive differences were observed in this sample. Findings suggest pre-existing neural differences prior to marijuana use may contribute to initiation of use and observed neural outcomes. Marijuana use may also interfere with thinning trajectories that contribute to morphological differences in young adulthood that are often observed in cross-sectional studies of heavy marijuana users.

ObjectiveTo assess the relationship between prenatal methamphetamine exposure (PME) and behavior problems at age 7.5 years and the extent to which early adversity mediated this relationship.Study designThe multicenter, longitudinal Infant Development, Environment, and Lifestyle study enrolled 412 mother-infant pairs at 4 sites. Methamphetamine-exposed participants (n = 204) were identified by self-report and/or gas chromatography/mass spectrometry confirmation of amphetamine and metabolites in infant meconium. Matched participants (n = 208) denied methamphetamine use and had a negative meconium screen. At the 7.5-year follow-up, 290 children with complete Child Behavior Checklist data and an early adversity index score were available for analysis (n = 146 exposed).ResultsPME was significantly associated with an increased early adversity index score (P < .001) and with increased externalizing, rule-breaking behavior, and aggressive behavior (P < .05). Early adversity was also associated with higher externalizing behavior scores. Early adversity significantly mediated the relationship between PME and behavioral problems. After adjusting the mediation model for sex, prenatal tobacco, alcohol, and marijuana exposures, and study site, the association of PME with early adversity remained significant.ConclusionsThough PME is associated with behavioral problems, early adversity may be a strong determinant of behavioral outcome for children exposed to methamphetamine in utero. Early adversity significantly mediated the relationship between PME and behavioral problems.

This study reviews the findings from the Infant Development, Environment, and Lifestyle (IDEAL) study, a multisite, longitudinal, prospective study designed to determine maternal outcome and child growth and developmental findings following prenatal methamphetamine exposure from birth up to age 7.5 years. These findings are presented in the context of the home environment and caregiver characteristics to determine how the drug and the environment interact to affect the outcome of these children. No neonatal abstinence syndrome requiring pharmacologic intervention was observed but heavy drug exposure was associated with increased stress responses in the neonatal period. Poorer inhibitory control was also observed in heavy methamphetamine exposed children placing them at high risk for impaired executive function. Independent of methamphetamine exposure, children with more responsive home environments to developmental and emotional needs demonstrated lower risks for internalizing and externalizing behavior.

BackgroundThe highly genetically variable enzyme CYP2A6 metabolizes nicotine to cotinine (COT) and COT to trans-3'-hydroxycotinine (3HC). The nicotine metabolite ratio (NMR, 3HC/COT) is commonly used as a biomarker of CYP2A6 enzymatic activity, rate of nicotine metabolism, and total nicotine clearance; NMR is associated with numerous smoking phenotypes, including smoking cessation. Our objective was to investigate the impact of different measurement methods, at different sites, on plasma and urinary NMR measures from ad libitum smokers.MethodsPlasma (n = 35) and urine (n = 35) samples were sent to eight different laboratories, which used similar and different methods of COT and 3HC measurements to derive the NMR. We used Bland-Altman analysis to assess agreement, and Pearson correlations to evaluate associations, between NMR measured by different methods.ResultsMeasures of plasma NMR were in strong agreement between methods according to Bland-Altman analysis (ratios, 0.82-1.16) and were highly correlated (all Pearson r > 0.96, P < 0.0001). Measures of urinary NMR were in relatively weaker agreement (ratios 0.62-1.71) and less strongly correlated (Pearson r values of 0.66-0.98, P < 0.0001) between different methods. Plasma and urinary COT and 3HC concentrations, while weaker than NMR, also showed good agreement in plasma, which was better than that in urine, as was observed for NMR.ConclusionsPlasma is a very reliable biologic source for the determination of NMR, robust to differences in these analytical protocols or assessment site.ImpactTogether this indicates a reduced need for differential interpretation of plasma NMR results based on the approach used, allowing for direct comparison of different studies.

This study examined the association between prenatal tobacco exposure (PTE) and infant cortisol reactivity at 9 months of infant age. Child sex and maternal parenting behavior were hypothesized moderators. The sample included 217 (148 tobacco-exposed, 69 non-exposed) mother-child dyads. Data used were obtained from pregnancy assessments, mother-infant feeding interactions at 2 months, and salivary cortisol at four time points in response to frustration at 9 months. Results indicated a significant association between PTE and infant cortisol that was moderated by infant sex and maternal intrusiveness. That is, PTE boys had lower cortisol than control boys, but there was no association between PTE and cortisol among girls. There was a significant association between PTE and cortisol among infants of intrusive mothers, but not among infants with non-intrusive mothers. Thus, PTE was associated with cortisol hypo-reactivity such that boys and non-exposed infants experiencing high maternal intrusiveness were at greater risk.