Longitudinal patterns of illicit drug use, antiretroviral therapy exposure and plasma HIV-1 RNA viral load among HIV-positive people who use illicit drugs.

OBJECTIVES: HIV-positive people who use illicit drugs (PWUD) experience elevated rates of HIV-associated morbidity and mortality compared with members of other key affected populations. Although suboptimal levels of access and adherence to antiretroviral therapy (ART) are common among HIV-positive PWUD, there is a need for studies investigating the possible biological impacts of noninjection illicit drug use among people living with HIV in real-world settings. METHODS: We accessed data from the ACCESS study, an ongoing prospective cohort of illicit drug users with systematic HIV viral load monitoring in a setting with universal care and ART dispensation records. We used multivariable generalized linear mixed models to estimate the longitudinal associations between noninjection use of crack cocaine, powder cocaine, opioids, methamphetamine, cannabis and alcohol on plasma HIV-1 RNA viral load, adjusted for ART exposure and relevant confounders. RESULTS: Between 2005 and 2018, 843 individuals from the ACCESS cohort were included and contributed to 8698 interviews. At baseline, the mean age was 43 years, 566 (67%) reported male sex and 659 (78%) used crack cocaine in the previous 6 months. In multivariable models adjusted for ART exposure, only crack cocaine use in the last 6 months was found to be significantly associated with higher HIV viral load. CONCLUSION: We observed significantly higher HIV viral load during periods of crack cocaine use independent of ART exposure. Our findings support further research to investigate the possible biological mechanisms of this effect.

Treatment of stimulant use disorder: A systematic review of reviews.

AIMS: Stimulant use disorder contributes to a substantial worldwide burden of disease, although evidence-based treatment options are limited. This systematic review of reviews aims to: (i) synthesize the available evidence on both psychosocial and pharmacological interventions for the treatment of stimulant use disorder; (ii) identify the most effective therapies to guide clinical practice, and (iii) highlight gaps for future study. METHODS: A systematic database search was conducted to identify systematic reviews and meta-analyses. Eligible studies were those that followed standard systematic review methodology and assessed randomized controlled trials focused on the efficacy of interventions for stimulant use disorder. Articles were critically appraised using an assessment tool adapted from Palmeteer et al. and categorized for quality as 'core' or 'supplementary' reviews. Evidence from the included reviews were further synthesized according to pharmacological or non-pharmacological management themes. RESULTS: Of 476 identified records, 29 systematic reviews examining eleven intervention modalities were included. The interventions identified include: contingency management, cognitive behavioural therapy, acupuncture, antidepressants, dopamine agonists, antipsychotics, anticonvulsants, disulfiram, opioid agonists, N-Acetylcysteine, and psychostimulants. There was sufficient evidence to support the efficacy of contingency management programs for treatment of stimulant use disorder. Psychostimulants, n-acetylcysteine, opioid agonist therapy, disulfiram and antidepressant pharmacological interventions were found to have insufficient evidence to support or discount their use. Results of this review do not support the use of all other treatment options. CONCLUSIONS: The results of this review supports the use of contingency management interventions for the treatment of stimulant use disorder. Although evidence to date is insufficient to support the clinical use of psychostimulants, our results demonstrate potential for future research in this area. Given the urgent need for effective pharmacological treatments for stimulant use disorder, high-quality primary research focused on the role of psychostimulant medications for the treatment of stimulant use disorder is needed.

High-intensity cannabis use is associated with retention in opioid agonist treatment: a longitudinal analysis.

BACKGROUND AND AIMS: Cannabis use is common among people on opioid agonist treatment (OAT), causing concern for some care providers. However, there is limited and conflicting evidence on the impact of cannabis use on OAT outcomes. Given the critical role of retention in OAT in reducing opioid-related morbidity and mortality, we aimed to estimate the association of at least daily cannabis use on the likelihood of retention in treatment among people initiating OAT. As a secondary aim we tested the impacts of less frequent cannabis use. DESIGN: Data were drawn from two community-recruited prospective cohorts of people who use illicit drugs (PWUD). Participants were followed for a median of 81 months (interquartile range = 37-130). SETTING: Vancouver, Canada. PARTICIPANTS: This study comprised a total of 820 PWUD (57.8% men, 59.4% of Caucasian ethnicity, 32.2% HIV-positive) initiating OAT between December 1996 and May 2016. The proportion of women was higher among HIV-negative participants, with no other significant differences. MEASUREMENTS: The primary outcome was retention in OAT, defined as remaining in OAT (methadone or buprenorphine/naloxone-based) for two consecutive 6-month follow-up periods. The primary explanatory variable was cannabis use (at least daily versus less than daily) during the same 6-month period. Confounders assessed included: socio-demographic characteristics, substance use patterns and social-structural exposures. FINDINGS: In adjusted analysis, at least daily cannabis use was positively associated with retention in OAT [adjusted odds ratio (aOR) = 1.21, 95% confidence interval (CI) = 1.04-1.41]. Our secondary analysis showed that compared with non-cannabis users, at least daily users had increased odds of retention in OAT (aOR = 1.20, 95% CI = 1.02-1.43), but not less than daily users (aOR = 1.00, 95% CI = 0.87-1.14). CONCLUSIONS: Among people who use illicit drugs initiating opioid agonist treatment in Vancouver, at least daily cannabis use was associated with approximately 21% greater odds of retention in treatment compared with less than daily consumption.