187359 Patterns of methamphetamine use by gender among injection drug users in Tijuana, Mexico

Tuesday, October 28, 2008

Melanie L.A. Rusch, PhD , Division of International Health and Cross Cultural Medicine, UCSD, La Jolla, CA
Maria Remedios Lozada, Dra , Patronato Pro-COMUSIDA, Tijuana, Mexico
Robin A. Pollini, PhD MPH , School of Medicine, University of California San Diego, La Jolla, CA
Alicia Vera, MPH , Division of International Health and Cross-cultural Medicine, University of California, San Diego, San Diego, CA
Thomas Patterson, PhD , Dept of Psychiatry, University of California, La Jolla, CA
Patricia Case, ScD , The Fenway Institute, Fenway Community Health, Boston, MA
Steffanie A. Strathdee, PhD , Department of Family and Preventive Medicine, University of California, San Diego, La Jolla, CA
Background: Tijuana, situated across from San Diego, CA, is a major drug trafficking route. Increased trafficking of methamphetamine in recent years has created a local consumption market. We examined factors associated with different types of methamphetamine use among male and female injecting drug users (IDUs).

Methods: From 2006-2007, IDUs ≥18 years old in Tijuana were recruited using respondent-driven sampling (RDS), interviewed with structured questionnaires and tested for HIV, syphilis and TB. Weighted logistic regression was used to assess associations with current methamphetamine use (past 6 months), stratified by gender.

Results: Among 1056 participants, methamphetamine use was reported by more females compared to males (80% vs. 68%, p=0.001). Smoking methamphetamine was also more common among females (70.9% vs. 50.1%; p<0.01). Among females (N=158), being aged <35 years (AOR: 5.3, 95% CI: 2.13 ĘC 13.12), and recent sex work (AOR: 2.4, 95% CI: 0.99-5.76) were associated with methamphetamine use. Among males (N=898), being aged <35 years (AOR: 2.1, 95% CI: 1.55-2.77), homelessness (AOR: 1.4 (0.93-2.20), and ever reporting sex with another man (MSM; AOR: 1.9, 95% CI: 1.39-2.69) were associated with methamphetamine use. HIV serostatus was not associated with use among either gender. Exploring modes of use among males indicated that while MSM was associated with methamphetamine injection, it was not associated smoking or snorting; however, recent sex work was associated with snorting methamphetamine.

Conclusions: Methamphetamine use is highly prevalent among IDUs in Tijuana. Routes of administration differed by gender and subgroup which has important implications for development of interventions and harm reduction.

Learning Objectives:
1.Identify differences in patterns of methamphetamine use by gender that impact risk for HIV through both injection and sexual risk. 2. Recognize the implications of different risks associated with different modes of use. 3. Discuss directions for harm reduction and risk reduction interventions that take the different risks by mode and gender into account.

Keywords: Drug Use, Epidemiology

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I am an Assistant Professor of Epidemiology in the Division of International Health and Cross Cultural Medicine, and I have my PhD in Epidemiology from Johns Hopkins University. I have worked for over 8 years on the epidemiology and policy of drug-related risks among IDU and other substance using populations.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.