Abstracts / Drug and Alcohol Dependence 146 (2015) e34–e117 e57

CYP2A6 metabolism in the development ofnicotine dependence in adolescents and youngadults

Emily Olfson 1, Joseph Bloom 1, Sarah Bertelsen 1,John Budde 1, Victor Hesselbrock 2, John Kramer 3,Alison Goate 1, Laura Bierut 1

1 Washington University School of Medicine, St.Louis, MO, United States2 University of Connecticut School of Medicine,Farmington, CT, United States3 University of Iowa Carver College of Medicine, IowaCity, IA, United States

Aims: To examine how variation in CYP2A6, the enzyme respon-sible for the majority of nicotine metabolism, influences nicotinedependence in a youth sample.

Methods: Since 2005, the Collaborative Study on the Geneticsof Alcoholism (COGA) has recruited participants ages 12–22 fromsix US sites with assessments every two years. A subsample of1,016 European ancestry individuals was genotyped for CYP2A6variants to calculate a previously described metabolism metric, andmore genotyping is underway. In this sample, 366 (36%) reportedsmoking at least 100 cigarettes and were considered smokers. Datawere analyzed using the Statistical Analysis System, and logis-tic regression was used to model nicotine dependence with theFagerstrom Test for Nicotine Dependence (FTND, score of 0-3 non-dependent smokers vs. >4 dependent smokers). Metabolizer status(slow metabolizers < 0.85 by metric), gender, and last interview agewere used as covariates.

Results: The sample was 40% female and 15% slow metaboliz-ers with a mean first interview age of 17 years and last interviewof 22 years. Among smokers, 51% of the normal metabolizers wereFTND dependent (n = 152/312), while 70% of the slow metabolizerswere dependent (n = 38/54). In the logistic regression model, beinga slow metabolizer was associated with increased risk of FTND diag-nosis after controlling for gender and last interview age (OR = 2.3,p = 0.009).

Conclusions: These preliminary findings suggest that CYP2A6variation linked to slow metabolism is associated with increasednicotine dependence risk in adolescents and young adults. Somestudies hypothesize that slow metabolism may increase sensitivityto nicotine in youth, causing increased progression to dependence.Future research will dissect the specific timing of smoking behav-iors in this population.

Financial support: This work was supported by U10AA008401from the National Institute of Health (NIH). EO was supported byT32GM007200 and UL1TR000448, sub-award TL1TR000449, fromthe NIH.

http://dx.doi.org/10.1016/j.drugalcdep.2014.09.524

Evaluating potential moderators of efficacy fora single-session computer-delivered 5Asintervention for smoking in pregnancy

Steven J. Ondersma 1,2, David M. Ledgerwood 1,Dace Svikis 3

1 Department of Psychiatry & BehavioralNeurosciences, Wayne State University, Detroit, MI,United States2 Merrill Palmer Skillman Institute, Wayne StateUniversity, Detroit, MI, United States3 Institute for Women’s Health, Psychology,Psychiatry; Ob/Gyn, Virginia CommonwealthUniversity, Richmond, VA, United States

Aims: In a previously published trial, a single-session,computer-delivered 5As/5Rs intervention (CD-5As) was associatedwith significant reductions in smoking (e.g., 24.5% 7-day point-prevalence abstinence at 10-week follow-up in the interventiongroup vs. 8.9% in the control group). The present study conductedsecondary data analysis to evaluate potential moderators of inter-vention efficacy.

Methods: The original trial randomly assigned 107 low-income,primarily African-American pregnant women reporting smokingduring pregnancy to intervention vs. control conditions and re-evaluated smoking 10 weeks later. The primary outcome in theoriginal study, as well is in the current analyses, was 7-daypoint prevalence abstinence per self-report confirmed with carbonmonoxide breath testing. Moderator analyses involved a series ofbinary logistic regressions, one for each of the four potential mod-erators of efficacy: smoking more than 10 cigarettes per day (26.2%of participants), nicotine dependence (positive score on the Fager-ström Test of Nicotine Dependence; 52.7% of participants), mentalillness (scoring above the published cutoff on the K6 screener;23.6% of participants), or living with someone who smokes (61.8%of participants). These equations entered experimental condition(intervention vs. control) and moderator variables before enteringa condition × moderator interaction term.

Results: None of the four interaction terms were significant,suggesting that the efficacy of the computerized 5As interventionwas not moderated by any of the four measures studied.

Conclusions: In this sample, a computer-delivered brief 5As/5Rsintervention for smoking during pregnancy was equally likely tohave a small to moderate effect on smoking, regardless of baselinesmoking frequency, nicotine dependence, maternal mental illness,or presence of other smokers in the home.

Financial support: DA021668.

http://dx.doi.org/10.1016/j.drugalcdep.2014.09.525