Association Between Marijuana Use and Condom Use: A Meta-Analysis of Between-Subject Event-Based Studies.

OBJECTIVE: With the current public health burden of sexually transmitted infections, it is important to identify factors affecting condom use. The association between marijuana use and condom use is especially important because of the increasing number of U.S. states legalizing marijuana; however, relevant research findings are mixed. The goal of this study was to perform a meta-analysis assessing the relationship between marijuana and condom use at instances of sexual intercourse. METHOD: A systematic search of four databases was performed. Data were extracted and pooled estimates were calculated using random-effects models with inverse variance weighting. Heterogeneity was evaluated using the Cochran Q chi-square test. RESULTS: Eleven studies were included. There was a statistically significant relationship between marijuana and condom use in the overall pooled analysis (odds ratio [OR] = 0.71, 95% CI [0.56, 0.89]), and studies were homogeneous, I2 = 12%, χ2(10) = 11.37, p = .33. Stratified analyses showed that although the pooled OR was not significant for adults (OR = 0.92, 95% CI [0.64, 1.33]), there was a significant relationship between condom use and marijuana use for adolescents (OR = 0.62, 95% CI [0.47, 0.82]). CONCLUSIONS: This meta-analysis found that the odds of condom use were lower for those who used marijuana around the time of intercourse than for those who did not, with this effect only significant for adolescents in a subgroup analysis. As the adolescent populations in this analysis were not representative of a general population of adolescents, future research should focus not only on those considered high risk.