Explaining associations between adolescent substance use and condom use

Purpose: This study examined different explanations for associations between adolescent substance use and lower condom use, in terms of the event-specific effects of alcohol or drugs, psychosocial factors, and sexual behaviors (intercourse frequency, greater number of partners and pill use). Methods: Pupils from 25 schools in Scotland, UK provided data on use of alcohol, tobacco, cannabis and psychosocial factors at ages 14 and 16 years; and sexual behaviors at age 16 years. Logistic regression was used to examine associations between substance use and condom use in those reporting intercourse more than once (n = 1322), adjusting for explanatory variables. Results: Regular use of any of the three substances at age 14 or 16 was associated with lower condom use at age 16, adjusting for gender and social background. The greatest attenuation of the substance use odds ratios was achieved by adjusting for all behaviors and psychosocial factors. This finding applied to different substance use groups, although cigarette-only and alcohol-only groups at age 16 differed in the relative importance of being "drunk or stoned" to other factors explaining condom use. Conclusions: Among adolescent substance users, being "drunk or stoned" at intercourse was only one factor related to not using condoms. Psychosocial factors (including attitudes to sexual risks and peer sexual norms) and having more sexual partners also explained substance users' condom use, with lesser effects due to greater intercourse frequency and pill use. Multiple explanations for substance use/condom use associations may guide counseling and education services.