Trajectories and Outcomes of Stimulant Drug Use among Men Who have Sex with Men (MSM) over a 4 year period

Background: Stimulant drug use is a predictor of HIV seroconversion and associated with other deleterious health effects among MSM. However, few studies have examined patterns and outcomes of stimulant drug use over time among MSM.

Methods: Within the Multicenter AIDS Cohort Study (n= 2457), we examined trajectories of stimulant drug use among MSM over a four year period (2004-2008). A semi-parametric, group-based approach was used to identify clustered patterns of use over time.

Findings: We identified five distinct patterns of stimulant drug use over the four year period: no use (69%), very low use (7%), increasing use (5%), decreasing use (8%) and consistent frequent use (11%). Men who did not use stimulants had a higher mean age and educational levels than all other groups and drank less than men in the decreasing or consistent frequent groups. Regarding outcomes, men who did not use stimulants had lower levels of depression symptoms than men in the increasing, decreasing or consistent frequent groups, scored lower on number of alcohol-related problems than all other groups, and higher on medication adherence measures than consistent frequent users.

Conclusions: Men who do not use stimulants had better scores on a number of health outcomes. However, a meaningful proportion of stimulant users either never used frequently or decreased use over time. Thus, MSM stimulant users may have important strengths in managing drug use that remain unstudied, which may be useful in substance abuse treatment and prevention efforts.