Prescribed psychostimulants and other pro-cognitive medications in bipolar disorder: A systematic review and meta-analysis of recurrence of manic symptoms.

OBJECTIVES: Clinicians are often hesitant to prescribe psychostimulants in bipolar disorder (BD) due to concerns of inducing (hypo)mania, despite limited published evidence on associations between prescribed psychostimulant use and recurrence of mood episodes in BD. The current systematic review and meta-analysis evaluated the emergence of (hypo)manic symptoms in patients with BD receiving prescribed psychostimulants or other pro-cognitive medications in euthymic or depressive states. METHODS: A systematic search was performed of MEDLINE, Embase, and PsychINFO from inception to April 5, 2023 and search of Clinicaltrials.gov and Clinicaltrialsregister.eu for unpublished data. References of included studies were hand-searched. Randomized trials and prospective longitudinal studies that evaluated psychostimulants and non-stimulant medications recommended for the treatment of ADHD by the Canadian ADHD practice guidelines were included. The review was reported in line with PRISMA guidelines and was preregistered on PROSPERO (CRD42022358588). RESULTS: After screening 414 unique records, we included 27 studies, of which five reported data that was quantitatively synthesized (n = 1653). The use of psychostimulants in BD was not associated with increased scores on the Young Mania Rating Scale in patients who were in a euthymic or depressed state (SMD IV -0.17; 95% CI, -0.40 to 0.06) compared to placebo. There was a high degree of study-level heterogeneity (I2 = 80%). A qualitative synthesis of studies revealed a limited risk of medication-induced manic symptoms. CONCLUSIONS: Our review provides preliminary evidence to suggest psychostimulants and non-stimulant ADHD medications have a limited risk of precipitating (hypo)mania symptoms. More extensive studies evaluating the safety and efficacy of these medications are warranted.

Expectancies of the Effects of Cannabis Use in Individuals with Social Anxiety Disorder (SAD).

Previous research has indicated that anticipating positive effects from cannabis use may be linked with increased frequency of cannabis consumption, yet these expectancies remain poorly understood in adults with social anxiety disorder (SAD). Thus, our study aimed to investigate the expectancies of the effects of cannabis use in 26 frequently using adults with SAD (age: 27.9 ± 7.3 years; 54% female) and 26 (age: 27.4 ± 6.7 years; 50% female) without. While no between-group differences were observed, both groups reported expecting tension reduction and relaxation (F = 0.001; p = 0.974), cravings, and physical effects (F = 1.10; p = 0.300), but denied global negative effects (F = 0.11; p = 0.744). The trajectory of cannabis use perceptions (further investigated in 12/26 participants/group) also showed no between-group differences. Before the initial use, positive perceptions may have led to initial and continuous cannabis consumption, while the symptoms of cannabis use disorder may have contributed to repeated use. Our data indicate that, regardless of psychiatric history, frequent cannabis-using adults are more likely to report positive expectancies, which are often associated with increased patterns of cannabis consumption. Psychoeducational programs and openly discussing the risks of cannabis may be beneficial in preventing and/or reducing cannabis use in people with SAD.

Perceptions, Experiences, and Patterns of Cannabis Use in Individuals with Mood and Anxiety Disorders in the Context of Cannabis Legalization and Medical Cannabis Program in Canada - A Qualitative Study.

INTRODUCTION: Perceptions of cannabis as a potential medical treatment for mood and anxiety disorders have been increasing in the context of legalizations, availability, and medical cannabis programs, though current evidence predominately indicates risks and negative effects of cannabis use (CU) on mental health outcomes. This study aims to understand motivations, perceptions, effects, and patterns of CU in individuals with mood and anxiety disorders. METHODS: Thirty-six adult patients diagnosed with mood or anxiety disorders, obsessive-compulsive disorder, or posttraumatic stress disorder who were currently using cannabis completed an in-depth qualitative interview on individual motivations, perceptions, experiences, effects, and patterns of their CU. The thematic analysis focused on phases of CU and sources of cannabis products and information. RESULTS: Reported motivations for initiation of CU included curiosity, peer pressure, and dissatisfaction with conventional treatments. Factors such as psychotropic effects and coping with mental health symptoms and insomnia contributed to the continuation of CU. More negative effects, including cognitive dysfunction, worsening of mood, and anxiety symptoms, were acknowledged with ongoing CU. Concerning findings included common initiation of CU before age 18, combined medical and recreational CU, rare consultation of medical professionals on CU, and potential effects and harms. DISCUSSION: Findings indicate individual complexity of motivations, perceptions, and patterns of CU in the study population. The reported potential beneficial effects of specific cannabis products should be further investigated. Findings emphasize patient-provider dialogue on both CU and conventional treatments. Information from this study can contribute to and inform the development of education, prevention, and intervention strategies.

Influence of CYP2C19, CYP2D6, and ABCB1 Gene Variants and Serum Levels of Escitalopram and Aripiprazole on Treatment-Emergent Sexual Dysfunction: A Canadian Biomarker Integration Network in Depression 1 (CAN-BIND 1) Study.

OBJECTIVES: Treatment-emergent sexual dysfunction is frequently reported by individuals with major depressive disorder (MDD) on antidepressants, which negatively impacts treatment adherence and efficacy. We investigated the association of polymorphisms in pharmacokinetic genes encoding cytochrome-P450 drug-metabolizing enzymes, CYP2C19 and CYP2D6, and the transmembrane efflux pump, P-glycoprotein (i.e., ABCB1), on treatment-emergent changes in sexual function (SF) and sexual satisfaction (SS) in the Canadian Biomarker Integration Network in Depression 1 (CAN-BIND-1) sample. METHODS: A total of 178 adults with MDD received treatment with escitalopram (ESC) from weeks 0-8 (Phase I). At week 8, nonresponders were augmented with aripiprazole (ARI) (i.e., ESC + ARI, n = 91), while responders continued ESC (i.e., ESC-Only, n = 80) from weeks 8-16 (Phase II). SF and SS were evaluated using the sex effects (SexFX) scale at weeks 0, 8, and 16. We assessed the primary outcomes, SF and SS change for weeks 0-8 and 8-16, using repeated measures mixed-effects models. RESULTS: In ESC-Only, CYP2C19 intermediate metabolizer (IM) + poor metabolizers (PMs) showed treatment-related improvements in sexual arousal, a subdomain of SF, from weeks 8-16, relative to CYP2C19 normal metabolizers (NMs) who showed a decline, F(2,54) = 8.00, p < 0.001, q = 0.048. Specifically, CYP2C19 IM + PMs reported less difficulty with having and sustaining vaginal lubrication in females and erection in males, compared to NMs. Furthermore, ESC-Only females with higher concentrations of ESC metabolite, S-desmethylcitalopram (S-DCT), and S-DCT/ESC ratio in serum demonstrated more decline in SF (r = -0.42, p = 0.004, q = 0.034) and SS (r = -0.43, p = 0.003, q = 0.034), respectively, which was not observed in males. ESC-Only females also demonstrated a trend for a correlation between S-DCT and sexual arousal change in the same direction (r = -0.39, p = 0.009, q = 0.052). CONCLUSIONS: CYP2C19 metabolizer phenotypes may be influencing changes in sexual arousal related to ESC monotherapy. Thus, preemptive genotyping of CYP2C19 may help to guide selection of treatment that circumvents selective serotonin reuptake inhibitor-related sexual dysfunction thereby improving outcomes for patients. Additionally, further research is warranted to clarify the role of S-DCT in the mechanisms underlying ESC-related changes in SF and SS. This CAN-BIND-1 study was registered on clinicaltrials.gov (Identifier: NCT01655706) on 27 July 2012.

Motivations for Cannabis Use in Individuals with Social Anxiety Disorder (SAD).

Social anxiety disorder (SAD) is a debilitating psychiatric condition. Consequently, it is common for those affected to resort to cannabis to cope with their symptoms. The primary objective of this study was to understand the differences between motivations for cannabis use in adults with and without SAD. We employed convergent, mixed methods to collect the data. Twenty-six individuals (age: 27.9 ± 7.3 years; 54% female) with and twenty-six (age: 27.4 ± 6.7 years; 50% female) without SAD were administered Marijuana Motives Measure (MMM). Motivations to initiate, continue, and maintain cannabis use were assessed in 12/26 participants in both groups using in-depth interviews. Cannabis weekly consumption was 3.8-fold and frequency 1.3-fold higher in the SAD group. Coping (F = 10.02; p <0.001; η2 = 0.46) and social (F = 2.81; p = 0.036; η2 = 0.19) motivations were also higher in the SAD group, after controlling for age, sex, and current CUD. The need to cope with symptoms of SAD may have been the driving force for repeated cannabis consumption. Psychoeducational programs educating children about the risk of using cannabis to cope with SAD should be implemented in vocational settings early on.

Cross-disorder GWAS meta-analysis of endocannabinoid DNA variations in major depressive disorder, bipolar disorder, attention deficit hyperactivity disorder, autism spectrum disorder, and schizophrenia.

The endocannabinoid system (ECS) is implicated in multiple mental disorders. In this study, we explored DNA variations in the ECS across major depressive disorder (MDD), bipolar disorder, attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and schizophrenia by performing a cross-disorder genome-wide association study (GWAS) meta-analysis. We obtained six datasets from the Psychiatric Genomics Consortium containing GWAS summary statistics from European cohorts (284,023 cases and 508,515 controls). Effective sample size weighted meta-analysis was performed for 2241 single nucleotide polymorphisms (SNPs) pertaining to gene bodies of 33 endocannabinoid genes using METAL, where an overall z-statistic is calculated for each marker based on a weighted sum of individual statistics. Heterogeneity was examined with I2 and X2 tests. MAGMA gene-based analysis was also performed. We identified nine SNPs significantly associated with a change in risk of having a mental disorder. The lead SNP was rs12805732 (Gene: Diacylglycerol Lipase Alpha; DAGLA). Four SNPs had substantial heterogeneity (I2>60 %). DAGLA had the strongest association with disease risk in gene-based analysis. Our findings suggest that the ECS may be a shared pathway in mental disorders. Future studies validating these findings would contribute to the identification of biomarkers of disease risk across multiple mental disorders.

Swept under the carpet: a qualitative study of patient perspectives on Long COVID, treatments, services, and mental health.

BACKGROUND: A constellation of often disabling long-term physical symptoms enduring after an acute SARS-COV-2 infection is commonly referred to as Long COVID. Since Long COVID is a new clinical entity, research is required to clarify treatment needs and experiences of individuals affected. This qualitative descriptive study aimed to provide insight into Long COVID treatment and service experiences and preferences of individuals experiencing Long COVID and the intersections with mental health. METHODS: The study was conducted out of a tertiary care mental health hospital, with online recruitment from the community across Canada. A total of 47 individuals (average age = 44.9) participated in one of 11 focus groups between June and December 2022. Five focus groups were conducted with participants who had pre-existing mental health concerns prior to contracting SARS-CoV-2, and six were with people with Long COVID but without pre-existing mental health concerns. A semi-structured interview guide asked about service experiences and service preferences, including mental health and well-being services. Discussions were recorded, transcribed, and analyzed using codebook thematic analysis. RESULTS: When accessing services for Long COVID, patients experienced: (1) systemic barriers to accessing care, and (2) challenges navigating the unknowns of Long COVID, leading to (3) negative impacts on patient emotional well-being and recovery. Participants called for improvements in Long COVID care, with a focus on: (1) developing Long COVID-specific knowledge and services, (2) enhancing support for financial well-being, daily living, and building a Long COVID community, and (3) improving awareness and the public representation of Long COVID. CONCLUSIONS: Substantial treatment barriers generate considerable burden for individuals living with Long COVID. There is a pressing need to improve treatment, social supports, and the social representation of Long COVID to create integrated, accessible, responsive, and ongoing support systems.

Toward personalized circuit-based closed-loop brain-interventions in psychiatry: using symptom provocation to extract EEG-markers of brain circuit activity.

Symptom provocation is a well-established component of psychiatric research and therapy. It is hypothesized that specific activation of those brain circuits involved in the symptomatic expression of a brain pathology makes the relevant neural substrate accessible as a target for therapeutic interventions. For example, in the treatment of obsessive-compulsive disorder (OCD), symptom provocation is an important part of psychotherapy and is also performed prior to therapeutic brain stimulation with transcranial magnetic stimulation (TMS). Here, we discuss the potential of symptom provocation to isolate neurophysiological biomarkers reflecting the fluctuating activity of relevant brain networks with the goal of subsequently using these markers as targets to guide therapy. We put forward a general experimental framework based on the rapid switching between psychiatric symptom states. This enable neurophysiological measures to be derived from EEG and/or TMS-evoked EEG measures of brain activity during both states. By subtracting the data recorded during the baseline state from that recorded during the provoked state, the resulting contrast would ideally isolate the specific neural circuits differentially activated during the expression of symptoms. A similar approach enables the design of effective classifiers of brain activity from EEG data in Brain-Computer Interfaces (BCI). To obtain reliable contrast data, psychiatric state switching needs to be achieved multiple times during a continuous recording so that slow changes of brain activity affect both conditions equally. This is achieved easily for conditions that can be controlled intentionally, such as motor imagery, attention, or memory retention. With regard to psychiatric symptoms, an increase can often be provoked effectively relatively easily, however, it can be difficult to reliably and rapidly return to a baseline state. Here, we review different approaches to return from a provoked state to a baseline state and how these may be applied to different symptoms occurring in different psychiatric disorders.

Associations between rumination, depression, and distress tolerance during CBT treatment for depression in a tertiary care setting.

BACKGROUND: Rumination is strongly associated with depressive symptom severity and course. However, changes in rumination during outpatient cognitive behavioral therapy (CBT), and their links to baseline features such as distress tolerance and clinical outcomes, have received limited attention. METHODS: 278 outpatients with depression received group or individual CBT. Measures of rumination, distress tolerance, and depression symptom severity were assessed at baseline and periodically during treatment. Mixed effect and regression-based models evaluated changes over time, and associations between rumination, distress tolerance and depression severity. RESULTS: Depression and rumination decreased throughout acute treatment. Rumination reduction was concurrently associated with depressive symptom reduction. Lower levels of rumination at each time point prospectively predicted lower depressive symptoms at the next time point. Distress tolerance measured at baseline was positively associated with depression symptom severity; the indirect effect on post-treatment depression symptoms via rumination measured mid-treatment was nonsignificant when rumination at baseline was accounted for. Changes in and associations between depression and rumination were replicated in sensitivity analyses; although changes in depression and rumination were smaller in magnitude in patients receiving treatment during COVID-19. LIMITATIONS: Additional assessment points would permit a more nuanced assessment of the role rumination may play in mediating the associations between distress tolerance and depression severity. Additional investigation of treatments in community settings may also further our understanding of variability in rumination during depression treatment. CONCLUSIONS: The current study provides unique real-world support for variability in rumination as a key indicator of change over the course of CBT for depression.

Psilocybin for treatment-resistant depression without psychedelic effects: study protocol for a 4-week, double-blind, proof-of-concept randomised controlled trial.

BACKGROUND: Randomised controlled trials (RCTs) of psilocybin have reported large antidepressant effects in adults with major depressive disorder and treatment-resistant depression (TRD). Given psilocybin's psychedelic effects, all published studies have included psychological support. These effects depend on serotonin 2A (5-HT2A) receptor activation, which can be blocked by 5-HT2A receptor antagonists like ketanserin or risperidone. In an animal model of depression, ketanserin followed by psilocybin had similar symptomatic effects as psilocybin alone. AIMS: To conduct a proof-of-concept RCT to (a) establish feasibility and tolerability of combining psilocybin and risperidone in adults with TRD, (b) show that this combination blocks the psychedelic effects of psilocybin and (c) provide pilot data on the antidepressant effect of this combination (compared with psilocybin alone). METHOD: In a 4-week, three-arm, 'double dummy' trial, 60 adults with TRD will be randomised to psilocybin 25 mg plus risperidone 1 mg, psilocybin 25 mg plus placebo, or placebo plus risperidone 1 mg. All participants will receive 12 h of manualised psychotherapy. Measures of feasibility will include recruitment and retention rates; tolerability and safety will be assessed by rates of drop-out attributed to adverse events and rates of serious adverse events. The 5-Dimensional Altered States of Consciousness Rating Scale will be a secondary outcome measure. RESULTS: This trial will advance the understanding of psilocybin's mechanism of antidepressant action. CONCLUSIONS: This line of research could increase acceptability and access to psilocybin as a novel treatment for TRD without the need for a psychedelic experience and continuous monitoring.

Out with AI, in with the psychiatrist: a preference for human-derived clinical decision support in depression care.

Advancements in artificial intelligence (AI) are enabling the development of clinical support tools (CSTs) in psychiatry to facilitate the review of patient data and inform clinical care. To promote their successful integration and prevent over-reliance, it is important to understand how psychiatrists will respond to information provided by AI-based CSTs, particularly if it is incorrect. We conducted an experiment to examine psychiatrists' perceptions of AI-based CSTs for treating major depressive disorder (MDD) and to determine whether perceptions interacted with the quality of CST information. Eighty-three psychiatrists read clinical notes about a hypothetical patient with MDD and reviewed two CSTs embedded within a single dashboard: the note's summary and a treatment recommendation. Psychiatrists were randomised to believe the source of CSTs was either AI or another psychiatrist, and across four notes, CSTs provided either correct or incorrect information. Psychiatrists rated the CSTs on various attributes. Ratings for note summaries were less favourable when psychiatrists believed the notes were generated with AI as compared to another psychiatrist, regardless of whether the notes provided correct or incorrect information. A smaller preference for psychiatrist-generated information emerged in ratings of attributes that reflected the summary's accuracy or its inclusion of important information from the full clinical note. Ratings for treatment recommendations were also less favourable when their perceived source was AI, but only when recommendations were correct. There was little evidence that clinical expertise or familiarity with AI impacted results. These findings suggest that psychiatrists prefer human-derived CSTs. This preference was less pronounced for ratings that may have prompted a deeper review of CST information (i.e. a comparison with the full clinical note to evaluate the summary's accuracy or completeness, assessing an incorrect treatment recommendation), suggesting a role of heuristics. Future work should explore other contributing factors and downstream implications for integrating AI into psychiatric care.

The therapygenetics of anxiety disorders.

Treatment of anxiety disorders primarily includes pharmacological treatment and psychotherapy, yet a substantial portion of patients do not experience sufficient clinical response. Given the significant impact of anxiety disorders on well-being and quality of life, it is pertinent to strive to ensure available treatments are of paramount efficacy. This review aimed to identify genetic variants and genes that may moderate the outcome of psychotherapy in patients with anxiety disorders, termed 'therapygenetics.' A comprehensive search of the current literature following relevant guidelines was conducted. Eighteen records were included in the review. Seven studies reported significant associations between genetic variants and response to psychotherapy. The most investigated polymorphisms were the serotonin transporter-linked polymorphic region (5-HTTLPR), nerve growth factor rs6330, catechol-O-methyltransferase Val158Met, and brain-derived neurotrophic factor Val166Met. However, current findings are inconsistent and thus do not support the use of genetic variants for the prediction of psychotherapy response in anxiety disorders.

Resting-state EEG delta and alpha power predict response to cognitive behavioral therapy in depression: a Canadian biomarker integration network for depression study.

Cognitive behavioral therapy (CBT) is often recommended as a first-line treatment in depression. However, access to CBT remains limited, and up to 50% of patients do not benefit from this therapy. Identifying biomarkers that can predict which patients will respond to CBT may assist in designing optimal treatment allocation strategies. In a Canadian Biomarker Integration Network for Depression (CAN-BIND) study, forty-one adults with depression were recruited to undergo a 16-week course of CBT with thirty having resting-state electroencephalography (EEG) recorded at baseline and week 2 of therapy. Successful clinical response to CBT was defined as a 50% or greater reduction in Montgomery-Åsberg Depression Rating Scale (MADRS) score from baseline to post-treatment completion. EEG relative power spectral measures were analyzed at baseline, week 2, and as early changes from baseline to week 2. At baseline, lower relative delta (0.5-4 Hz) power was observed in responders. This difference was predictive of successful clinical response to CBT. Furthermore, responders exhibited an early increase in relative delta power and a decrease in relative alpha (8-12 Hz) power compared to non-responders. These changes were also found to be good predictors of response to the therapy. These findings showed the potential utility of resting-state EEG in predicting CBT outcomes. They also further reinforce the promise of an EEG-based clinical decision-making tool to support treatment decisions for each patient.

Weight-gain independent effect of mirtazapine on fasting plasma lipids in healthy men.

Treatment with mirtazapine, a widely prescribed antidepressant, has been linked to weight gain and dyslipidemia. Whether dyslipidemia occurs secondary to increased appetite due to antidepressant treatment, or due to direct pharmacological effects of mirtazapine is unknown. The aim of this analysis is to complement our previously published results of the effect of mirtazapine on metabolism and energy substrate partitioning from a proof-of-concept, open-label clinical study (ClinicalTrials.gov NCT00878540) in 12 healthy males (20-25 years). We report the effect of a seven-day administration of mirtazapine 30 mg per day on weight and lipid metabolism in healthy men under highly standardized conditions with respect to diet, physical activity and day-night-rhythm and under continuous clinical observation. After a 7-day administration of mirtazapine 30 mg, we observed a statistically significant increase in triglyceride levels (mean change + 4.4 mg/dl; 95% CI [- 11.4; 2.6]; p = 0.044) as well as TG/HDL-C ratio (mean change + 0.2; 95% CI [- 0.4; 0.1]; p = 0.019) and a decrease in HDL-cholesterol (mean change - 4.3 mg/dl; 95% CI [2.1; 6.5]; p = 0.004), LDL-cholesterol (mean change - 8.7 mg/dl; 95% CI [3.8; 13.5]; p = 0.008), total cholesterol (mean change - 12.3 mg/dl; 95% CI [5.4; 19.1]; p = 0.005), and non-HDL-C (mean change - 8.0 mg/dl; 95% CI [1.9; 14.0]; p = 0.023). Notably, weight (mean change - 0.6 kg; 95% CI [0.4; 0.8]; p = 0.002) and BMI (mean change - 0.2; 95% CI [0.1; 0.2]; p = 0.002) significantly decreased. No change in waist circumference (mean change - 0.4 cm; 95% CI [- 2.1; 2.9]; p = 0.838) or waist-to-hip-ratio (mean change 0.0; 95% CI [- 0.0; 0.0]; p = 0.814) was observed. This is the first study showing unfavorable changes in lipid metabolism under mirtazapine in healthy individuals despite highly standardized conditions including dietary restriction, and despite the observation of a decrease of weight. Our findings support the hypothesis that mirtazapine has direct pharmacological effects on lipid metabolism. ClinicalTrials.gov: NCT00878540.

Systematic review of structured care pathways in major depressive disorder and bipolar disorder.

BACKGROUND: Structured care pathways (SCPs) consist of treatment algorithms that patients advance through with the goal of achieving remission or response. These SCPs facilitate the application of current evidence and adequate treatment, which potentially benefit patients with mood disorders. The aim of this systematic review was to provide an updated synthesis of SCPs for the treatment of depressive disorders and bipolar disorder (BD). METHOD: PubMed, PsycINFO, and Embase were searched through June 2022 for peer-reviewed studies examining outcomes of SCPs. Eligibility criteria included being published in a peer-reviewed journal in the English language, reporting of intervention used in the SCP, and having quantitative outcomes. Studies Cochrane risk of bias tool was used to assess quality of RCTs. RESULTS: Thirty-six studies including 15,032 patients were identified for qualitative synthesis. Six studies included patients with BD. The studies were highly heterogeneous in design, outcome measures, and algorithms. More than half of the studies reported superiority of SCPs over treatment as usual, suggesting that the standardized structure and consistent monitoring inherent in SCPs may be contributing to their effectiveness. We also found accumulating evidence supporting feasibility of SCPs in different settings, although dropout rates were generally higher in SCPs. The studies included were limited to being published in peer-reviewed journals in English language. The heterogeneity of studies did not allow quantitative evaluation. CONCLUSIONS: The findings of our study suggest that SCPs are equally or more effective than treatment as usual in depression and BD. Further studies are required to ascertain their effectiveness, particularly for BD, and to identify factors that influence their feasibility and success.

ABCB1 Gene Variants and Antidepressant Treatment Outcomes: A Systematic Review and Meta-Analysis Including Results from the CAN-BIND-1 Study.

The P-glycoprotein efflux pump, encoded by the ABCB1 gene, has been shown to alter concentrations of various antidepressants in the brain. In this study, we conducted a systematic review and meta-analysis to investigate the association between six ABCB1 single-nucleotide polymorphisms (SNPs; rs1045642, rs2032582, rs1128503, rs2032583, rs2235015, and rs2235040) and antidepressant treatment outcomes in individuals with major depressive disorder (MDD), including new data from the Canadian Biomarker and Integration Network for Depression (CAN-BIND-1) cohort. For the CAN-BIND-1 sample, we applied regression models to investigate the association between ABCB1 SNPs and antidepressant treatment response, remission, tolerability, and antidepressant serum levels. For the meta-analysis, we systematically summarized pharmacogenetic evidence of the association between ABCB1 SNPs and antidepressant treatment outcomes. Studies were included in the meta-analysis if they investigated at least one ABCB1 SNP in individuals with MDD treated with at least one antidepressant. We did not find a significant association between ABCB1 SNPs and antidepressant treatment outcomes in the CAN-BIND-1 sample. A total of 39 studies were included in the systematic review. In the meta-analysis, we observed a significant association between rs1128503 and treatment response (T vs. C-allele, odds ratio = 1.30, 95% confidence interval = 1.15-1.48, P value (adjusted) = 0.024, n = 2,526). We did not find associations among the six SNPs and treatment remission nor tolerability. Our findings provide limited evidence for an association between common ABCB1 SNPs and antidepressant outcomes, which do not support the implementation of ABCB1 genotyping to inform antidepressant treatment at this time. Future research, especially on rs1128503, is recommended.

Response Inhibition and Predicting Response to Pharmacological and Cognitive Behavioral Therapy Treatments for Major Depressive Disorder: A Canadian Biomarker Integration Network for Depression Study.

BACKGROUND: Major depressive disorder (MDD) is associated with various cognitive impairments, including response inhibition. Deficits in response inhibition may also underlie poor antidepressant treatment response. Recent studies revealed that the neurobiological correlates of response inhibition can predict response to pharmacological treatments. However, the generalizability of this finding to first-line nonpharmacological treatments, particularly cognitive behavioral therapy, remains to be investigated. METHODS: Data from two independent treatment protocols were combined, one in which 65 patients with MDD underwent treatment with escitalopram, and the other in which 41 patients with MDD underwent a course of cognitive behavioral therapy. A total of 25 healthy control subjects were also recruited. Neural correlates of response inhibition were captured by participants completing a Go/NoGo task during electroencephalography recording. Response inhibition-related measures of interest included the amplitudes of the N2 and P3 event-related potentials. RESULTS: Pretreatment P3 amplitude, which has been linked to both the motor and cognitive aspects of response inhibition, was a significant predictor of change in depressive symptoms following escitalopram and cognitive behavioral therapy treatment. A greater pretreatment P3 amplitude was associated with a greater reduction in depressive severity. In addition, the pretreatment P3 amplitude was found to be significantly greater at baseline in remitters than in nonremitters and healthy control subjects. CONCLUSIONS: The integrity of response inhibition may be critical for a successful course of pharmacological or psychological treatment for MDD. Electrophysiological correlates of response inhibition may have utility as a general prognostic marker of treatment response in MDD. Future studies may investigate the benefit of preceding first-line treatments with interventions that improve response inhibition in MDD.

Factors Associated With Initiation of Antidepressant Medication in Adults With Type 1 and Type 2 Diabetes: A Primary Care Retrospective Cohort Study in Ontario, Canada.

OBJECTIVES: Depression in patients with diabetes mellitus is common and associated with poorer outcomes. This study aims to identify demographic, socioeconomic and medical factors associated with the initiation of antidepressant medication after a diagnosis of diabetes in adult patients without a previous prescription for antidepressants. We also examined frequency of primary care visits in the year after antidepressant initiation compared with the year before treatment began. METHODS: This was a retrospective cohort study using routinely collected electronic medical record data spanning January 2011 to December 2019 from the University of Toronto Practice-based Research Network (UTOPIAN) Data Safe Haven. Our primary outcome was a first prescription for an antidepressant in patients with diabetes. We used a mixed-effects logistic regression model to identify sociodemographic and medical factors associated with this event. RESULTS: Among 22,750 patients with diabetes mellitus, 3,055 patients (13.4%) began taking an antidepressant medication. Increased odds of antidepressant initiation were observed in younger patients (odds ratio [OR], 1.77; 95% confidence interval [CI], 1.39 to 2.26), females (OR, 1.60; 95% CI, 1.46 to 1.7), those receiving insulin treatment (OR, 1.59; 95% CI, 1.43 to 1.78) and cases of polypharmacy (OR, 3.67; 95% CI, 3.29 to 4.11). There was an increase in the mean number of primary care visits from 4.6 to 5.9 per year after antidepressant initiation. CONCLUSIONS: In patients with diabetes, age, sex and medical characteristics were associated with the initiation of antidepressants. These patients accessed primary care more frequently. Screening and prevention of depression, particularly in these subgroups, could reduce its personal and systemic burdens.

Identification of Endocannabinoid Predictors of Treatment Outcomes in Major Depressive Disorder: A Secondary Analysis of the First Canadian Biomarker Integration Network in Depression (CAN-BIND 1) Study.

INTRODUCTION: An increasing number of studies are examining the link between the endocannabinoidome and major depressive disorder (MDD). We conducted an exploratory analysis of this system to identify potential markers of treatment outcomes. METHODS: The dataset of the Canadian Biomarker Integration Network in Depression-1 study, consisting of 180 patients with MDD treated for eight weeks with escitalopram followed by eight weeks with escitalopram alone or augmented with aripiprazole was analyzed. Association between response Montgomery-Asberg Depression Rating Scale (MADRS; score reduction≥50%) or remission (MADRS score≤10) at weeks 8 and 16 and single nucleotide polymorphisms (SNPs), methylation, and mRNA levels of 33 endocannabinoid markers were examined. A standard genome-wide association studies protocol was used for identifying SNPs, and logistic regression was used to assess methylation and mRNA levels. RESULTS: Lower methylation of CpG islands of the diacylglycerol lipase alpha gene (DAGLA) was associated with non-remission at week 16 (DAGLA; OR=0.337, p<0.003, q=0.050). Methylation of DAGLA was correlated with improvement in Clinical Global Impression (p=0.026), Quick Inventory of Depressive Symptomatology (p=0.010), and Snaith-Hamilton Pleasure scales (p=0.028). We did not find any association between SNPs or mRNA levels and treatment outcomes. DISCUSSION: Methylation of DAGLA is a promising candidate as a marker of treatment outcomes for MDD and needs to be explored further.

Effects of 28 days of cannabis abstinence on cognition in major depressive disorder: A pilot study.

BACKGROUND AND OBJECTIVES: Cannabis is a widely used substance that may impair select cognitive domains, including attention and memory. Problematic cannabis use is a common clinical problem among patients with major depressive disorder (MDD). Few studies have investigated the effects of cannabis abstinence on cognition in MDD. Thus, our study aimed to determine whether a 28-day period of cannabis abstinence is associated with improvements in cognition in patients with MDD and comorbid cannabis use disorder (CUD). METHODS: We evaluated the effects of 28 days of cannabis abstinence on cognition in MDD patients with comorbid CUD facilitated by contingency management, motivational interviewing, psychoeducation, and coping-skills training (N = 11). Primary outcomes included Baseline to Day 28 changes in verbal memory and learning, while secondary outcomes included Baseline to Day 28 changes in working memory, visuospatial working memory (VSWM), visual search speed, mental flexibility, response inhibition, attention, manual dexterity, and fine motor movement. RESULTS: Eight participants (72.7%) met the pre-specified criteria for cannabis abstinence and three participants significantly reduced their cannabis use (≥90%). Visual search speed, selective attention, and VSWM improved over the study period. These improvements were not associated with changes in cannabis metabolite levels from baseline to endpoint. DISCUSSION AND CONCLUSIONS: Our findings suggest that 28 days of cannabis abstinence may improve select cognitive domains in patients with MDD and comorbid CUD. SCIENTIFIC SIGNIFICANCE: This is the first study to longitudinally examine the effects of cannabis on cognition in MDD. CLINICAL TRIAL: Effects of Cannabis Abstinence on Symptoms and Cognition in Depression (NCT03624933; https://www. CLINICALTRIALS: gov).