Substance use, sexual intercourse, and condom nonuse among depressed adolescents and young adults

To examine daily- and event-level associations of substance use with occurrence of sex and condom nonuse among depressed youth.

Depressed, sexually active outpatients aged 15-22 years reported alcohol use, marijuana use, and sex on a personal digital assistant for 2 weeks. If they reported sex, participants indicated partner type and condom use. Data were analyzed for participants who reported both substance use and sex events (N = 39) using generalized estimating equations. Daily-level models compared the likelihood of sex and of condom nonuse between days on which participants did or did not use substances. Event-level models examined the likelihood of sex in the 2, 6, and 12 hours after substance use and the likelihood of condom nonuse if substances were used in the preceding 2, 6, and 12 hours.

Participants reported 307 sex events (180 unprotected) and 391 substance use events on 572 days. Substance use was associated with increased odds of sex on the same day, but not after adjusting for weekend. Depressed youth were less likely to have sex within 2 hours after substance use and more likely to have sex within 12 hours after marijuana use. There was no main effect of substance use on condom nonuse; however, there was a significant interaction such that on weekdays, condom nonuse was less likely when substances were used within 6 hours before sex.

The findings from this small, predominantly female sample suggest that contextual factors, not intoxication, influence associations of substance use with sexual behavior in depressed youth.