The EDGE Project

Thomas L. Patterson, Principal Investigator

The Edge

Fact Sheet

Study Title Behavior Change and Maintenance Intervention for HIV+ MSM Methamphetamine Users
Funding Source National Institutes of Health: Office of AIDS Research and National Institute of Drug Abuse
Grant Number R01 DA021115-01
Project Period 09/30/2006 - 04/30/2011
Total Costs
(entire project period)
Performance Site HIV Neurobehavioral Research Center (HNRC), San Diego, CA
Notes This study represents a continuation of an earlier study, "Promoting Safer Sex in HIV+ MSM Methamphetamine Users" (R01 DA012116-01A2), which was also nicknamed "EDGE" and ran from 2000 to 2005. The main innovation in the current project is the introduction of a behavior maintenance component (see abstract, below).

The concept for the original EDGE project, in turn, grew out of an earlier study, "Brief Targeted Intervention for HIV+ Persons" (R01 MH56264).


Increased numbers of HIV/AIDS cases among Men who have Sex with Men (MSM) have been linked to the use of methamphetamine—a powerful stimulant that is widely used across the USA. Studies conducted with MSM from San Diego to New York show a strong association between methamphetamine use and high risk sexual practices. Heightened concern about the spread of HIV/AIDS among MSM has led to an immediate need for the development of sexual risk reduction interventions for HIV+ methamphetamine users. A major goal of intervention development is the longer-term maintenance of behavior change. This study's primary objective is to evaluate the efficacy of an intervention that integrates an individual behavior change component with a behavioral maintenance component, which together are hypothesized to result in maximum, long-term treatment effects. Our intervention will utilize a randomized, pretest, multiple posttest, control group design. Four hundred fifty sexually active HIV+ MSM who regularly use methamphetamine and who have had unprotected sex with HIV negative or unknown status partner(s) will be randomly assigned to one of three conditions: (1) individual behavior change counseling (N=150); (2) individual behavior change counseling plus group-format maintenance sessions (N=150); or (3) an attention-control condition (time-equivalent to condition 2) which addresses diet, exercise, and HIV and includes group maintenance sessions (N=150). The behavior change component of the intervention (based on social cognitive theory and motivational interviewing) addresses five intervention domains: the contexts of unsafe sex and drug use; condom use; negotiation of safer sex practices; disclosure of HIV seropositivity to sex partners; and enhancement of social supports. The eight session, group-format maintenance component will use clinical strategies borrowed from relapse prevention to help participants sustain or improve positive behavioral changes (e.g., by identifying high risk situations that can lead to sexual slipups and developing effective coping strategies). Followup assessments will be conducted at 6, 12 and 18 months. A variety of outcomes will be examined (e.g., unprotected anal sex, number of HIV-negative partners, partner types). Subgroup differences in the efficacy of the intervention based on ethnicity, patterns of drug use (e.g., binge use, injection, polydrug use) and key psychosocial factors (e.g., sexual compulsivity, experiences of abuse) will be explored.


(In reverse chronological order)

Semple, S.J., Zians, J., Grant, I., and Patterson, T.L. Methamphetamine use, impulsivity, and sexual risk behavior among HIV+ men who have sex with men. Journal of Addictive Diseases. In Press, October 2006.

Mausbach, B.T., Semple, S.J., Strathdee, S.A., Zians, J., and Patterson, T.L. Effectiveness of a behavioral intervention for increasing safer sex behaviors in HIV+ methamphetamine users: Results from the EDGE study. Drug and Alcohol Dependence. In Press, October 2006.

Semple, S.J., Zians, J., Grant, I., and Patterson, T.L. Sexual compulsivity in a sample of HIV+ methamphetamine-using Men who have Sex with Men. AIDS and Behavior 10 (5): 587-98, 2006.

Semple, S.J., Zians, J., Grant, I. and Patterson, T.L. Sexual risk behavior of HIV+ methamphetamine-using men who have sex with men: The role of partner serostatus and partner type. Archives of Sexual Behavior. 35 (4), 2006.

Semple, S.J., Zians, J., Grant, I. and Patterson, T.L. Impulsivity and methamphetamine use. Journal of Substance Abuse Treatment. 29: 85-93, 2005.

Patterson, T.L., Semple, S.J., Zians, J.K., and Strathdee, S.A. Methamphetamine-using HIV-positive men who have sex with men: Correlates of polydrug use. Journal of Urban Health. 82 (I Suppl 1): i120-6, 2005.

Patterson, T.L, and Semple, S.J. Coping, Methamphetamine, and HIV. In: The Neurology of AIDS. 2nd Ed. pp. 753-762. Gendelman H.E., Grant I., Lipton, S., Everall, I., and Swindell, S. (Eds). Oxford University Press, Oxford U.K., 2005.

Semple, S.J., Patterson, T.L., and Grant, I. A comparison of injection and non-injection methamphetamine-using HIV positive men who have sex with men. Drug and Alcohol Dependence. 76 (2): 203-212, 2004.

Semple, S.J., Patterson, T.L., and Grant, I. Psychosocial characteristics and sexual risk behavior of HIV+ men who have anonymous sex partners. Psychology and Health. 19 (1): 71-87, 2004.

Patterson, T.L., and Semple. S.J. Sexual risk reduction among HIV positive drug using men who have sex with men (MSM). Journal of Urban Health. 80 (4): 77-87, 2003.

Semple, S.J., Patterson, T.L., and Grant, I. Binge use of methamphetamine among HIV-positive men who have sex with men: Pilot data and HIV prevention implications. AIDS Education and Prevention. 15 (2): 133-147, 2003.

Patterson, T.L., Shaw, W.S., and Semple, S.J. Reducing the sexual risk behaviors of HIV+ individuals: Outcome of a randomized controlled trial. Annals of Behavioral Medicine. 25 (2): 137-145, 2003.

Semple, S.J., Patterson, T.L., and Grant, I. HIV+ gay and bisexual men: Predictors of unsafe sex. AIDS Care. 15 (1): 3-15, 2003.

Semple, S.J., Patterson, T.L., and Grant, I. Motivations associated with methamphetamine use among HIV+ men who have sex with men. Journal of Substance Abuse Treatment. 22 (3): 149-156, 2002.

Semple, S.J., Patterson, T.L., and Grant, I. Gender differences in the sexual risk practices of HIV+ heterosexual men and women. AIDS and Behavior. 6 (1): 45-54, 2002.

Semple, S.J., Patterson, T.L., and Grant, I. Partner type and sexual risk behavior among HIV positive gay and bisexual men: Social cognitive correlates. AIDS Education and Prevention. 12 (4): 340-356, 2000.

Semple, S.J., and Patterson, T.L. Psychosocial predictors of unprotected anal intercourse among HIV seropositive gay men who volunteer for a sexual risk reduction intervention. AIDS Education and Prevention. 12 (5): 416-430, 2000.

Semple, S.J., Patterson, T.L. and Grant, I. The sexual negotiation behavior of HIV+ gay and bisexual men. Journal of Consulting and Clinical Psychology. 68 (5): 934-937, 2000.

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