A new repeated measures approach of sexual and substance use risk behaviors among patients in transmitted disease clinics

s / Drug and Alcohol Dependence 156 (2015) e102–e182 e171 Results: 40 participants (60% male, age =22±2) of the target sample of 114were included in this analysis. Preliminary data suggest that, in the driving only condition, following distance behind a slowmoving vehicle increased in the active group 48h after smoking (p<0.05). Although not statistically significant, trends were observed in reductionof verbal recallmemory, increase in omission and commission errors of a sustained attention task, and increase in total collisions in the driving only scenario at both 24 and 48h post-dose. Conclusions: Preliminary data suggest that there may be some residual effects of cannabis on driving but findings are not conclusive. An increase in the sample sizewill help to yieldmoredefinitive results. Financial support: Funded by the Canadian Institutes of Health Research. http://dx.doi.org/10.1016/j.drugalcdep.2015.07.463 A new repeated measures approach of sexual and substance use risk behaviors among patients in transmitted disease clinics Yue Pan1, Lisa R. Metsch2, James Sorensen3, Daniel J. Feaster1 1 Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, United States 2 Columbia University, New York, NY, United States 3 University of California, San Francisco, San Francisco, CA, United States Aims: Although extensive studies have examined sexual and substance use behaviors that put people at risk for sexually transmitted infections (STI) including HIV, most focus on an overall measure of aggregate risk or a few simple and particular sub-types of sexual acts. We explored creating a more sensitive measure to assess how the relative characteristics of the sex acts determine the level of risk in which an individual choses to engage. There were two aims: (1) describe a new approach to examine the count of sexual acts using a fully disaggregated repeatedmeasuredesign, (2) showhowthisnewmeasures couldbeused toevaluate interactions between substance use, STI and other health outcomes. Methods: We analyzed data from Project Aware, a randomized clinical trial conducted among 5012 patients in 9 STD clinics in the US. Profiles of 16 different types of sexual acts were assessed using the repeatedmeasures approach. Potential interactions of the sex acts – having a primary/non-primary sex partner; partner’s HIV status; vaginal/anal; involvementof substanceusewithsexact; and patterns of substance use were examined. Generalized Estimating Equations (GEE) with negative binomial models were used. Results: Overall, participants had 2.1 partners and 23.3 condomless sex acts in the last 6 months. 56% reported ever using drugs, 6% were injection drug users, and 16% reported binge drinking in the last 6 months. Participants with problematic drug use (IRR=3.24,p<0.0001) andSTI (IRR=1.38,p=0.02)weremore likely to report an increased count of sex acts. Significant interactions were found for substance use with sex and problematic drug use (p<0.0001), partner status with STI prevalence (p=0.04) and incidence (p=0.01). Conclusions: This approach extends our understanding of how people make choices among sexual risk behaviors. The repeated measures approach may be useful in future research on disaggregated characteristics of sex acts. Financial support: RC2 DA028973 & R21 DA038641. http://dx.doi.org/10.1016/j.drugalcdep.2015.07.464 Age and gender effects on subjective drug effect of d-amphetamine Raina Pang1,2, Matthew Kirkpatrick2,3, Nicholas Goldenson1,2, Casey Guillot1,2, Adam Leventhal1,2 1 University of Southern California, Los Angeles, CA, United States 2 Department of Preventive Medicine, University of Southern California, Azusa, CA, United States 3 Preventive Medicine, University of Southern California, Los Angeles, CA, United States Aims: Prior studies suggest that sex differences in damphetamine response are related to hormonal fluctuations that occur during the luteal phase. Thus, studies control for sex differences by running females during the follicular phase when hormones are relatively low. However, studies showing no sex differences under these conditions have relatively small sample sizes. Thus, it is still unclear if there are sex differences – unrelated to luteal phase hormonal fluctuations– in d-amphetamine response. Agemayalsobean importantpredictor of subjectivedrug response, as illicit drug use varies by age. Few experimental studies have investigated the effect of age on drug response. The present study assessed gender and age as predictors of subjective drug response. Methods: Healthy stimulant-naive volunteers (n=75 normally cyclingwomen in the follicular phase;n=29men) aged18–35completed this two-session, double-blind,within-subjects studyduring which they received a single dose of 20-mg oral d-amphetamine or placebo in counterbalanced order. Subjective measures of drug response were completed at repeated intervals before and after drug administration over a 4-h period and under the curve drug response difference scores (e.g. d-amphetamine – placebo) computed. Partial correlations were run to evaluate relationships between sex, age, and subjective drug response. Results:After controlling for age,males reportedgreater subjective responses on the Drug Effects Questionnaire (DEQ) ‘Feel Drug’, ‘Like Drug’ and ‘Want More’ (rs = .20–.21, ps = .01–.04). After controlling for gender, younger individuals reported greater scores on the DEQ ‘Want More’ (r=−.26, p= .007). Conclusions: These results might suggest age and gender differences in abuse liability for young adults who may be prescribed d-amphetamine for clinical conditions (e.g., ADHD or narcolepsy) or start experiment with d-amphetamine recreationally. Financial support: TRDRP grant 22FT-0062, NIDA grants R21DA034768 and K08-DA025041. http://dx.doi.org/10.1016/j.drugalcdep.2015.07.465 School context and marijuana use among Maryland high school students Elizabeth Parker1, Renee M. Johnson1, Sarah Lindstrom Johnson2, Catherine Bradshaw3,4 1 Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States 2 Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, United States 3 Curry School of Education, University of Virginia, Charlottesville, VA, United States 4 Johns Hopkins Center for the Prevention of Youth Violence, Baltimore, MD, United States Aims: We examined: (1) whether the prevalence of marijuana use among high school students varied across schools, and (2)