Methamphetamine abuse as a barrier to HIV medication adherence among gay and bisexual men

The methamphetamine epidemic: implications for HIV prevention and treatment

Methamphetamine and related amphetamine compounds are among the most commonly used illicit drugs, with over 35 million users worldwide. In the United States, admissions for methamphetamine treatment have increased dramatically over the past 10 years. Methamphetamine use is prevalent among persons with HIV infection and persons at risk for HIV, particularly among men who have sex with men. In addition to being associated with increased sexual risk behavior, methamphetamine causes significant medical morbidity, including neurologic deficits, cardiovascular compromise, dental decay, and skin infections, all of which may be worsened in the presence of HIV/AIDS. Methamphetamine use may also result in decreased medication adherence, particularly during "binging" episodes. Behavioral counseling remains the standard of treatment for methamphetamine dependence, although the effectiveness of most counseling interventions has not been rigorously tested. Pharmacologic and structural interventions may prove valuable additional interventions to reduce methamphetamine use.

Methamphetamine-dependent gay men's disclosure of their HIV status to sexual partners

Disclosure of one's HIV status to a potential sexual partner has important HIV prevention implications. This paper qualitatively evaluates the social and sexual contexts that influence disclosure of HIV status among methamphetamine-dependent gay men enrolled in an outpatient drug treatment research program. As part of an open-ended, semi-structured interview, 34 HIV-positive and HIV-negative men discussed how, when, to whom and under what circumstances they reveal information about their HIV status. The four factors that influence participants' decision to disclose include: (1) an HIV-negative sexual partner's disclosure; (2) sexual venue (private versus public); (3) primary versus non-primary partner; and (4) the perceived risk of the sexual act. Sexual encounters among the men in this sample often occurred in public environments with non-primary partners, and involved use of illicit substances. In these social and sexual contexts, both HIV-positive and HIV-negative participants believed that it is HIV-negative rather than HIV-positive men who should initiate safer sex dialogue and safer sex practices. Findings are helpful in crafting HIV-prevention interventions targeting substance-using gay men whose sexual practices place them at high-risk for HIV-infection.

Effect of methamphetamine on the pharmacokinetics of dextromethorphan and midazolam in rats

Methamphetamine is the fourth most frequently reported compound associated with drug abuse on admission of patients to treatment centres after cocaine, heroin and marijuana. It is metabolized in the organism with a reaction that is catalyzed by cytochrome P450, mainly by the CYP2D and CYP3A subfamily, 4-hydroxyamphetamine and amphetamine being dominant metabolites. The present pharmacokinetic study was undertaken to investigate the possible influence of methamphetamine (10 mg/kg, i.p., once daily for six days) on the pharmacokinetics of dextromethorphane as a model substrate for rat cytochrome P-4502D2 and midazolam as a model substrate for CYP3A1/2. Animals received a single injection of dextromethorphane (10 mg/kg) or midazolam (5 mg/kg) in the tail vein 24 h after the last dose of methamphetamine or administration of placebo. The results of pharmacokinetic analysis showed a significantly increased rate of dextrorphane and 3-hydroxymorphinan formation, and a marked stimulatory effect of methamphetamine on CYP2D2 metabolic activity. Similarly, the kinetics of midazolam's metabolic conversion to hydroxy derivates of midazolam indicated a significant increase in CYP3A1/2 activity. The results showed that the administration of methamphetamine significantly stimulated the metabolic activity of CYP2D2 as well as that of CYP3A1/2. With regard to the high level of homology between human and rat CYP isoforms studied, the results may have a clinical impact on future pharmacotherapy for methamphetamine abuse.

Risk factors for early syphilis among gay and bisexual men seen in an STD clinic: San Francisco, 2002-2003

BACKGROUND

Substantial increases in syphilis among gay and bisexual men have been reported in San Francisco.

GOAL

To identify risk factors for early syphilis infection among gay and bisexual men attending the San Francisco municipal STD clinic (City Clinic).

STUDY

Cross-sectional, self-administered, behavioral survey of gay and bisexual men attending City Clinic between November 2002 and March 2003 linked with electronic medical record data.

RESULTS

Among 1318 gay and bisexual men surveyed, 53 (4.0%) were diagnosed with early syphilis. The final multivariate model included nonwhite race (OR = 2.1 [1.1-4.4]), HIV-infection (OR = 3.9 [2.0-7.7]), using both methamphetamine and sildenafil (Viagra(R)) (OR = 6.2 [2.6-14.9]), using methamphetamine without sildenafil (OR = 3.2 [1.3-7.6]), using sildenafil without methamphetamines (OR = 0.9 [0.3-2.9]), stronger gay community affiliation (OR = 2.3 [1.2-4.6]), and having recent Internet partners (OR = 2.1 [1.0-4.3]).

CONCLUSIONS

Syphilis prevention efforts should address methamphetamine and sildenafil use among gay and bisexual men and require strong and substantive involvement with the gay community to address syphilis in San Francisco.

Integration of motivational interviewing and cognitive behavioral therapy to improve HIV medication adherence and reduce substance use among HIV-positive men and women: results of a pilot project

Directly addressing HIV medication adherence and substance use together is ideal in light of the research on the complex connections between these two behaviors. This paper describes the development of a pilot program in which a combined motivational interviewing and cognitive behavioral therapy intervention was used to increase adherence to highly active antiretroviral therapy (HAART) and reduce substance use in HIV-infected adults. The main goals of the pilot study were (1) to confirm the ability to recruit HIV-positive substance users taking HAART; (2) to demonstrate the ability to retain participants over the course of an eight-session intervention; and (3) to examine changes in substance use and HAART adherence from pretreatment to posttreatment. Twelve HIV-positive adults with a substance use disorder participated in an 8-week intervention, which consisted of weekly individual sessions with a trained therapist. Results showed that despite the small sample size, there was a significant reduction in substance use from pretreatment to posttreatment. No statistically significant differences were found for changes in HIV medication adherence, but the trends suggest the potential for positive results with a larger sample. Retention for all eight sessions of the treatment was 73.3%. Eighty percent completed the 3-month follow-up assessment. Participants reported high therapeutic alliance reflecting comfort with their therapists and in the treatment. Overall, the pilot demonstrated feasibility and acceptability of the treatment. Furthermore, results suggest that this may, in fact, be an effective intervention to reduce substance use and improve HIV medication adherence.