Cannabis and Anxiety: A Critical Review.

Introduction: Cannabis has been reported to have both anxiogenic and anxiolytic effects. Habitual cannabis use has been associated with anxiety disorders (AD). The causal pathways and mechanisms underlying the association between cannabis use (CU)/cannabis use disorder (CUD) and anxiety remain unclear. We examined the literature via a systematic review to investigate the link between cannabis and anxiety. The hypotheses studied include causality, the common factor theory, and the self-medication hypothesis. Methods: Critical systematic review of published literature examining the relationship of CU/CUD to AD or state-anxiety, including case reports, literature reviews, observational studies, and preclinical and clinical studies. A systematic MEDline search was conducted of terms including: [anxiety], [anxiogenic], [anxiolytic], [PTSD], [OCD], [GAD], [cannabis], [marijuana], [tetrahydrocannabinol], [THC]. Results: While several case-control and cohort studies have reported no correlation between CU/CUD and AD or state anxiety (N = 5), other cross-sectional, and longitudinal studies report significant relationships (N = 20). Meta-analysis supports anxiety correlating with CU (N = 15 studies, OR = 1.24, 95% CI: 1.06-1.45, p = 0.006) or CUD (N = 13 studies, OR = 1.68, 95% CI: 1.23-2.31, p = 0.001). PATH analysis identifies the self-medication hypothesis (N = 8) as the model that best explains the association between CU/CUD and AD or state-anxiety. Despite the support of multiple large cohort studies, causal interpretations (N = 17) are less plausible, while the common factor theory (N = 5), stress-misattribution hypothesis, and reciprocal feedback theory lack substantial evidential support. Conclusion: The association between cannabis and anxiety is best explained by anxiety predisposing individuals toward CU as a method of self-medication. A causal relationship in which CU causes AD incidence is less likely despite multiple longitudinal studies suggesting so.

Effects of Opioid Withdrawal on Psychobiology in People Living with HIV.

OBJECTIVE: Many persons with opioid use disorders (OUDs) have HIV disease and experience clinically significant stress after they enroll in abstinence-based treatment and undergo medically assisted withdrawal. We examined whether opioid withdrawal affects virologic control, inflammatory markers, cognition, and mood in persons with an OUD and HIV, and explored whether measures of withdrawal stress, such as activation of the HPA axis, contribute to alterations in immune function, cognition, and mood. METHOD AND PARTICIPANTS: Study participants were 53 persons with HIV who were admitted for OUD treatment at the City Addiction Hospital in Saint Petersburg, Russian Federation. Participants were examined at admission, at the anticipated peak of withdrawal 3 to 7 days after the last day of a clonidine-based withdrawal process lasting 7 to 14 days, and 3 to 4 weeks after completing withdrawal. At these times, participants received medical exams and were evaluated for symptoms of withdrawal, as well as cognition and mood. Viral load, plasma cortisol, DHEA sulfate ester (DHEA-S), interleukin-6 (IL-6), and soluble CD14 (sCD14) were determined. Multivariable models examined the relationships between markers of HPA activation and the other parameters over time. RESULTS: HPA activation as indexed by cortisol/DHEA-S ratio increased during withdrawal, as did markers of immune activation, IL-6 and sCD14. There were no significant associations between viral load and indicators of HPA activation. In longitudinal analyses, higher cortisol/DHEA sulfate was related to worse cognition overall, and more mood disturbance. Increase in IL-6 was associated with worse cognitive performance on a learning task. There were no significant associations with sCD14. CONCLUSIONS: Worsening of cognition and measures of mood disturbance during withdrawal were associated with activation of the HPA axis and some measures of inflammation. Whether repeated episodes of opioid withdrawal have a cumulative impact on long-term HIV outcomes and neurocognition is a topic for further investigation.

Genetic Variations in EIF2AK3 are Associated with Neurocognitive Impairment in People Living with HIV.

Based on emerging evidence on the role for specific single-nucleotide variants (SNVs) in EIF2AK3 encoding the integrated stress response kinase PERK, in neurodegeneration, we assessed the association of EIF2AK3 SNVs with neurocognitive performance in people with HIV (PWH) using a candidate gene approach. This retrospective study included the CHARTER cohort participants, excluding those with severe neuropsychiatric comorbidities. Genome-wide data previously obtained for 1047 participants and targeted sequencing of 992 participants with available genomic DNA were utilized to interrogate the association of three noncoding and three coding EIF2AK3 SNVs with the continuous global deficit score (GDS) and global neurocognitive impairment (NCI; GDS ≥ 0.5) using univariable and multivariable methods, with demographic, disease-associated, and treatment characteristics as covariates. The cohort characteristics were as follows: median age, 43.1 years; females, 22.8%; European ancestry, 41%; median CD4 + T cell counts, 175/µL (nadir) and 428/µL (current). At first assessment, 70.5% used ART and 68.3% of these had plasma HIV RNA levels ≤ 200 copies/mL. All three noncoding EIF2AK3 SNVs were associated with GDS and NCI (all p < 0.05). Additionally, 30.9%, 30.9%, and 41.2% of participants had at least one risk allele for the coding SNVs rs1805165 (G), rs867529 (G), and rs13045 (A), respectively. Homozygosity for all three coding SNVs was associated with significantly worse GDS (p < 0.001) and more NCI (p < 0.001). By multivariable analysis, the rs13045 A risk allele, current ART use, and Beck Depression Inventory-II value > 13 were independently associated with GDS and NCI (p < 0.001) whereas the other two coding SNVs did not significantly correlate with GDS or NCI after including rs13045 in the model. The coding EIF2AK3 SNVs were associated with worse performance in executive functioning, motor functioning, learning, and verbal fluency. Coding and non-coding SNVs of EIF2AK3 were associated with global NC and domain-specific performance. The effects were small-to-medium in size but present in multivariable analyses, raising the possibility of specific SNVs in EIF2AK3 as an important component of genetic vulnerability to neurocognitive complications in PWH.

Neurocognition and its predictors in a linguistically and culturally diverse cohort of people with HIV.

Objective: HIV/AIDS disproportionately affects Black and Latino people in the United States, yet there is a lack of research on predictors of neurocognitive outcomes in these groups. We examined neurocognitive performance and its key predictors across White, Black, and Latino people with HIV (PWH). Method: Participants included 586 PWH of White, Black, and Latino (English- and Spanish-speaking) background. Neurocognition was assessed via demographically-adjusted Fluid Cognition Composite T-scores from the NIH-Toolbox cognition battery, and individual tests comprising this composite. Predictors examined included sociodemographic and HIV disease characteristics, and medical, psychiatric and substance comorbidities. Results: Compared to White PWH, English-speaking Latino PWH had lower T-scores on the Fluid Cognition Composite, as well as Flanker Inhibition and Picture Sequence Memory tests. While there were no other significant group differences on Fluid Cognition, both Latino PWH language groups performed worse than Black PWH on Flanker Inhibition, and Black PWH performed worse than White PWH on List Sorting. Separate multivariable linear regression models by ethnic/racial/language group showed that significant correlates of worse Fluid Cognition included depressive symptoms among White PWH; hepatitis C co-infection among Black PWH; hypertension among English-speaking Latino PWH; and higher estimated duration of HIV disease and depressive symptoms in Spanish-speaking Latino PWH. Conclusions: Findings suggest worse neurocognition among English-speaking Latino PWH compared to Whites. Predictors of neurocognitive function among PWH differ across ethnic/racial and language groups. Consideration of these HIV disease characteristics and comorbidities may be valuable in developing targeted culturally-relevant interventions aimed at ameliorating neurocognitive dysfunction among diverse PWH.