Mood, Marijuana-Associated Coitus and Condom Use Among Adolescent Women: An Event-Level Analysis Devon J. Hensel, Ph.D. J. Dennis Fortenberry, M.D., M.S. Donald P. Orr, M.D. Section of Adolescent Medicine Indiana University School of Medicine

Background Research has suggested that marijuana use is associated with sexual risk behaviors

Background Existing event level studies have produced mixed results Failure to also consider other factors related to marijuana use and to sexual risk: –Partnership characteristics –Regular patterns of sexual behavior –Intrapersonal

Objective To model the effects of marijuana- associated coitus as a mediator of event-level mood, sexual interest and relationship variables on condom use among adolescent women

Methods: Sample Adolescent women (N=267): –14 to 17 years of age at enrollment –Reported ever trying marijuana –89.9% African American –Recruited from three primary care adolescent clinics in Indianapolis, Indiana

Methods: Data Daily sexual diaries: –Alternating 90-day intervals, over 27 months –Daily record of coitus, mood, marijuana use, condom use and relationship variables

Methods: Outcome Variables Marijuana-Associated Coitus (no/yes) Condom Use (no/yes)

Methods: Predictor Variables Domains: –Regular coital behaviors –Partnership characteristics –Intrapersonal factors

Methods: Predictor Variables Regular Coital Behaviors Recent sexual activity (past 7 days: no/yes) Recent marijuana use (past 7 days, not associated with sex: no/yes) Recent marijuana-associated coitus (past 7 days: no/yes) Usual condom use (past 7 days: no/yes)

Methods: Predictor Variables Partnership Characteristics Partner support (4-items,  =0.93) Time with partner (1 item; scale: 1-4)

Methods: Predictor Variables Intrapersonal Variables Vaginal bleeding (no/yes) Positive mood (3-items,  =0.84) Negative mood (3-items;  =0.81) Sexual interest (1 item, scale: 1-4)

Methods: Procedure Structural equation modeling Full information maximum likelihood (FIML) –Alternative analyses: generalized estimating logistic regression –Compare robustness of FIML to within subject correlation of observations AMOS, 5.0

Results: All Diary Days N = 84,931 (partner) diary days Coitus: 5.4% (4610/84,931) of all days Coitus associated with marijuana: 17.48% (806/4610) of all coital events

Results: Bivariate Coitus Not Associated With Marijuana Coitus Associated With Marijuana VariableMean (SE) Partner Support* 3.21 (.02)2.96 (.05) Positive Mood* 9.86 (.08)9.17 (.02) Negative Mood* 5.49 (.06)6.50 (.12) Sexual Interest 2.79 (.03)2.78 (.05) Time With Partner 4.43 (.01)4.50 (.03) *p<.000

Results: Bivariate NoYesTotal No 2857 (75.1%) 617 (76.5%) 3474 (75.4%) Yes 947 (24.9%) 189 (23.5%) 1136 (25.6%) Total Marijuana Associated Coitus Condom Use Х 2 (1) = , p<.000

B = * B = 0.13*B = -0.02* B = 0.75* B = 0.35* *p<.05

B = -0.01* B = 0.82* B = -0.01* B = -0.02* B = -0.04* B = -0.01* *p<.05

B = * B = 0.75* B = -0.04* *p<.05 B = 0.13* B = 0.35*

Discussion Substance-associated coitus: less than 20% of all coital events Marijuana-associated coitus appears to be associated with decreased condom use Effect size comparable to most other predictors

Discussion This association may not be causal Event level behavior reflected established patterns of behaviors Negative mood may suggest that both marijuana and coitus used to elevate mood

Limitations Does not assess motivations for sex No method for disentangling within day effects Unclear how marijuana changes usual patterns of condom use

Implications STI prevention efforts may benefit from targeting regular coital behaviors: –Recent marijuana use –Recent marijuana associated coitus –Usual condom use

Sources of Support NIAID U01AI3194 NIAID T32AI07637 NICHD R01 HD HRSA/T71 MC