Abstract
Background: Chronic inflammation contributes to aging and organ dysfunction in the general population, and is a particularly important determinant of morbidity and mortality among people with HIV (PWH). The effect of cannabis use on chronic inflammation is not well understood among PWH, who use cannabis more frequently than the general population. Materials and Methods: We evaluated participants in the Multicenter AIDS Cohort Study (MACS) beginning in 2004 with available data on cannabis use and inflammatory biomarkers. Associations of current cannabis use with plasma concentrations of inflammatory markers were adjusted for hepatitis C, tobacco smoking, and comorbidities. Markers were analyzed individually and in exploratory factor analysis (EFA). Results: We included 1352 men within the MACS. Twenty-seven percent of HIV-negative men, 41% of HIV viremic men, and 35% of virologically suppressed men reported cannabis use at baseline. Among cannabis users, 20-25% in all groups defined by HIV serostatus were daily users, and the same proportion reported weekly use. The remaining ∼50% of users in all groups reported monthly or less frequent use. Four biomarker groupings were identified by EFA: Factor 1: immune activation markers; Factor 2: proinflammatory cytokines; Factor 3: Th1- and Th2-promoting cytokines; and Factor 4: inflammatory chemokines. In EFA, daily users had 30% higher levels of Factor 2 biomarkers than nonusers (p=0.03); this was the only statistically significant difference by cannabis use status. Among individual markers, concentrations of IL-1β, IL-2, IL-6, and IL-8 (Factor 2); IL-10 (Factor 3); and BAFF (Factor 1) were higher (p<0.05) among daily cannabis users than among nonusers, after adjusting for HIV serostatus and other covariates. Discussion: Associations between daily cannabis use and proinflammatory biomarker levels did not differ by HIV serostatus. Further prospective studies with measured cannabis components are needed to clarify the impact of these compounds on inflammation. Our findings can facilitate for hypothesis generation and selection of biomarkers to include in such studies.