Abstract

Background: There is evidence that substance use is associated with risky sexual behaviors among the youth, but the multiplicity of sexual partners has been largely overlooked, particularly in Latin America and low- and middle-income countries. Objective: We evaluated the association between the frequency of substance use–alcohol, marijuana, cocaine, and cocaine paste–and the number of sexual partners among young people between the ages of 15 and 29 living in Chile. Methods: We used data from the Ninth National Youth Survey, a cross-sectional study with a multi-stage random sampling design. Association measures were estimated through separate generalized negative binomial regression models (NB-P), adjusting for sexual onset, sexual orientation, and sociodemographic factors. Results: We found an association between the use (once monthly or less) of alcohol (IRR = 1.18, 95%CI [1.04, 1.34]) and cocaine use (IRR = 1.4, 95%CI [1.11, 1.76]) and the number of sexual partners in the previous twelve months. Using alcohol and marijuana several times per month was associated with a risk increase of 1.33 (95%CI [1.16, 1.54]) and 1.22 (95%CI [1.09, 1.36]) respectively. Conclusions: Alcohol, marijuana, and cocaine use was associated with an increased risk of having multiple sexual partners compared to nonuse among young people. These findings should be complemented by analyzing other risky sexual behaviors, patterns of substance use, and health outcomes.