Sex differences in bipolar disorder: Impact of lifetime cannabis use on clinical course, functioning, and quality of life in bipolar disorder

Sex differences in bipolar disorder: The dorsolateral prefrontal cortex as an etiopathogenic region

Bipolar disorder (BD) is worldwide a prevalent mental illness and a leading risk factor for suicide. Over the past three decades, it has been discovered that sex differences exist throughout the entire panorama of BD, but the etiologic regions and mechanisms that generate such differences remain poorly characterized. Available evidence indicates that the dorsolateral prefrontal cortex (DLPFC), a critical region that controls higher-order cognitive processing and mood, exhibits biological disparities between male and female patients with psychiatric disorders, which are highly correlated with the co-occurrence of psychotic symptoms. This review addresses the sex differences in BD concerning epidemiology, cognitive impairments, clinical manifestations, neuroimaging, and laboratory abnormalities. It also provides strong evidence linking DLPFC to the etiopathogenesis of these sex differences. We emphasize the importance of identifying gene signatures using human brain transcriptomics, which can depict sexually different variations, explain sex-biased symptomatic features, and provide novel targets for sex-specific therapeutics.

Avatar Intervention for Cannabis Use Disorder in Individuals with Severe Mental Disorders: A Pilot Study

Cannabis use disorder (CUD) is a complex issue, even more so when it is comorbid with a severe mental disorder (SMD). Available interventions are at best slightly effective, and their effects are not maintained over time. Therefore, the integration of virtual reality (VR) may increase efficacy; however, it has not yet been investigated in the treatment of CUD. A novel approach, avatar intervention for CUD, uses existing therapeutic techniques from other recommended therapies (e.g., cognitive behavioral methods, motivational interviewing) and allows participants to practice them in real-time. During immersive sessions, participants are invited to interact with an avatar representing a significant person related to their drug use. This pilot clinical trial aimed to evaluate the short-term efficacity of avatar intervention for CUD on 19 participants with a dual diagnosis of SMD and CUD. Results showed a significant moderate reduction in the quantity of cannabis use (Cohen's d = 0.611, p = 0.004), which was confirmed via urinary quantification of cannabis use. Overall, this unique intervention shows promising results. Longer-term results, as well as comparison with classical interventions in a larger sample, are warranted through a future single-blind randomized controlled trial.

Associations between cannabis use, cannabis use disorder, and mood disorders: longitudinal, genetic, and neurocognitive evidence

RATIONALE

Cannabis use among people with mood disorders increased in recent years. While comorbidity between cannabis use, cannabis use disorder (CUD), and mood disorders is high, the underlying mechanisms remain unclear.

OBJECTIVES

We aimed to evaluate (1) the epidemiological evidence for an association between cannabis use, CUD, and mood disorders; (2) prospective longitudinal, genetic, and neurocognitive evidence of underlying mechanisms; and (3) prognosis and treatment options for individuals with CUD and mood disorders.

METHODS

Narrative review of existing literature is identified through PubMed searches, reviews, and meta-analyses. Evidence was reviewed separately for depression, bipolar disorder, and suicide.

RESULTS

Current evidence is limited and mixed but suggestive of a bidirectional relationship between cannabis use, CUD, and the onset of depression. The evidence more consistently points to cannabis use preceding onset of bipolar disorder. Shared neurocognitive mechanisms and underlying genetic and environmental risk factors appear to explain part of the association. However, cannabis use itself may also influence the development of mood disorders, while others may initiate cannabis use to self-medicate symptoms. Comorbid cannabis use and CUD are associated with worse prognosis for depression and bipolar disorder including increased suicidal behaviors. Evidence for targeted treatments is limited.

CONCLUSIONS

The current evidence base is limited by the lack of well-controlled prospective longitudinal studies and clinical studies including comorbid individuals. Future studies in humans examining the causal pathways and potential mechanisms of the association between cannabis use, CUD, and mood disorder comorbidity are crucial for optimizing harm reduction and treatment strategies.

Multimodal Correlates of Cannabis Use among U.S. Veterans with Bipolar Disorder: An Integrated Study of Clinical, Cognitive, and Functional Outcomes

Objective: Cannabis use (CU) is common among persons with bipolar disorder (BD). Evidence suggests that CU is associated with poorer outcomes among persons with BD; however, these findings remain inconsistent. The present exploratory study aims to examine clinical, functional, and cognitive correlates of CU among persons with BD. Methods: U.S. veterans with BD type I who participated in a large-scale, nationwide study were categorized into four groups: current CU, past CU, past other drug use, and no drug use. Bivariate analyses, univariate analyses of covariance, and Levene's Test for Equality of Variance were used to compare groups on clinical, cognitive, and functional measures. Results: Of 254 (84.6% male) veterans with BD type I included in the analyses, 13 (5.1%) had current CU, 37 (14.5%) past CU, 77 (30.3%) past other drug use, and 127 (50%) reported no drug use. BD with CU was associated with post-traumatic stress disorder (PTSD) and experiencing lifetime suicidal ideation. Notably, current CU was associated with higher working memory performance, compared to both past CU and no drug use. Likewise, current CU was associated with higher functional capacity, compared to past CU as well as no drug use. Conclusions: These findings contribute to the growing literature on the complex effects of cannabis on BD. As the commercialization and legalization of cannabis increases, further research in this area is warranted to quantify posed risks to this population, and thereby guide clinical decision-making.

Confirmatory evaluation of the bipolar depression rating scale (BDRS) in a large sample of female patients with bipolar depression

OBJECTIVE

The Bipolar Depression Rating Scale (BDRS) is a structured rating scale designed to assess depressive and mixed symptoms in bipolar disorder (BD). Previous studies evaluating the scale have been performed on small samples or on patients in a depressive phase, but not on patients in a mixed or manic phase. This study evaluated the Persian version of the BDRS regarding its factor structure, reliability, and validity in a large sample of Iranian women with BD in a depressive or mixed/manic phase.

METHODS

Three-hundred and one female BD inpatients completed the BDRS, the Beck Depression Inventory-II (BDI-II), the Hamilton Depression Rating Scale (HDRS), the Montgomery-Åsberg Depression Rating Scale (MADRS), and the Young Mania Rating Scale (YMRS).

RESULTS

The BDRS demonstrated a three-factor structure with good reliability. The BDRS and its psychological and somatic symptom clusters had stronger correlations with other measures of depressive symptoms than a measure of mania. The BDRS mixed symptom cluster also had a stronger correlation with a measure of mania than other measures of depression, supporting the scales' convergent and discriminant validity.

CONCLUSIONS

The BDRS demonstrated psychometric validity in assessing depressive and mixed symptoms in Iranian women with BD in a depressive or mixed/manic phase.KEY POINTSThe Bipolar Depression Rating Scale (BDRS) was validated in Iranian women with BD.The BDRS showed a three-factor structure, similar to the original validation.The BDRS had good reliability based on Omega and test-retest coefficients.The findings provided evidence for the convergent and discriminant validity of the BDRS.

The relationship between cannabis use and cognition in people with bipolar disorder: A systematic scoping review

Bipolar disorder (BD) and cannabis use are highly comorbid and are each associated with cognitive impairment.  Given the prevalence of cannabis use in people with BD, it is important to understand whether the two interact to impact cognitive function. We performed a systematic scoping review to determine what is currently known in this field. We systematically searched PubMed, Embase, CINAHL, Web of Science, and PsycINFO for studies on the relationship between cannabis use and cognition in people with BD or relevant animal models. Six observational human studies and no animal studies met inclusion criteria. Two studies found cannabis use in BD was associated with better performance in some cognitive domains, while three studies found no association. One study found cannabis use in BD was associated with worse overall cognition. Overall, most identified studies suggest cannabis use is not associated with significant cognitive impairment in BD; however, the scope of knowledge in this field is limited, and more systematic studies are clearly required. Future studies should focus on longitudinal and experimental trials, and well-controlled observational studies with rigorous quantification of the onset, frequency, quantity, duration, and type of cannabis use, as well as BD illness features.