Environmental Factors Associated with Psychotropic Drug Use in Brazilian Nightclubs.

The purpose of this study was to identify environmental factors associated with patterns of psychotropic drug use in nightclubs. Mixed methods were used to investigate psychotropic drugs consumption among patrons of 31 nightclubs in São Paulo, Brazil. A total of 1822 patrons at the entrance and exit of the venues and 30 staff members of the nightclubs were interviewed. The observational data were collected through 307 h of observational research using a structured guide to register environmental measures. Psychotropic drug use in nightclubs was classified into three categories (1: no drugs; 2: legal drugs [e.g., alcohol and tobacco]; or 3: illicit drugs regardless of alcohol and tobacco use). Illicit drugs used were self-reported by patrons, and alcohol use was measured using a breathalyzer. The data were analyzed in clusters using correlated multinomial logistic regression models. The following environmental variables were associated with illicit drug use in nightclubs: all-you-can-drink service (adjusted odds ratio (aOR) = 11.84, 95%CI [4.06;34.57]) and light effects, such as laser and "disco lights" (aOR = 24.49, 95%CI [8.48;70.77]). The number of bouncers per capita × 100 and the presence of two or more dance floors were inversely associated with the use of illicit drugs (aOR = 0.26, 95%CI [0.11;0.65], and aOR = 0.13, 95%CI [0.06;0.29], respectively). Legal drug use was associated with all-you-can-drink service (aOR = 2.17, 95%CI [1.43;5.04]), the presence of two or more dance floors (aOR = 2.06, 95%CI [1.40;3.05]), and the number of bouncers per capita × 100 (aOR = 1.39, 95%CI [1.22;1.59]). These findings suggest that this is a multivariate phenomenon that would require an integrated approach involving the venue owners, staff members, patrons, local governments, and law enforcement agencies.