Gay men who use methamphetamine three times more likely to get HIV, says US study

Gay men who use the recreational drug methamphetamine are three times more likely to test positive for HIV than non- users of the drug, according to a study conducted in San Francisco and published in the September 2^nd edition of AIDS. The investigators also found that gay men who use methamphetamine are more likely to report unprotected anal sex.

An earlier study conducted in San Francisco found that over a third of gay men who attended ‘circuit parties’ used methamphetamine, and that these methamphetamine users were approximately two and a half times more likely to report unprotected anal sex with a man of a different or unknown HIV status during a ‘party’ weekend than non-users of the drug.

Investigators from the US Centers for Disease Control, San Francisco Department of Public Health, and University of California designed a study to determine the frequency of methamphetamine use amongst gay men seeking an anonymous HIV test; the social, demographic and behavioural characteristics associated with methamphetamine use; and, the association between methamphetamine use and HIV seroconversion.

A total of 2991 gay men were included in the investigators’ analysis. The median age was 34 years, 71% were white, 10% were Hispanic, 11% were Asian or Pacific and 8% were of other races or ethnicities.

Overall, 290 men (10%) reported using methamphetamine in the previous year and 236 (8%) said they had had sex whilst using the drug. Compared with non-users of the drug, men who took methamphetamine were more likely to report unprotected anal sex in the previous year (odds ratio 2.3) and to report ten or more sexual partners (odds ratio 2.5). The investigators also found that users of methamphetamine were significantly more likely to be under 35 years of age (p

A total of 108 men (4%) tested HIV-positive. Testing suggested that 34 of these men had been infected within the last six months, and of these men eight (24%) had used methamphetamine.

The investigators calculated that the overall HIV incidence was 2.5% per year. However, their analysis indicated that the rate of new annual infections was much higher amongst methamphetamine users at 6%, and 8% per year amongst men who used methamphetamine during sex.

Even when the investigators controlled for the use of other recreational drugs, alcohol and poppers they still found a strong association between methamphetamine use and recent infection with HIV (odds ratio 2.5).

The investigators call their findings “worrisome” and recommend that HIV counsellors and physicians collect data and “counsel their clients and patients on the dangers of amphetamine addiction and the link between amphetamine use, high-risk sex practices, and HIV infection.”