Stimulant use may have less of a negative effect on health outcomes for people living with HIV than previously thought. A team of researchers reported that they found no association between any frequency of stimulant use and mortality, and only a modest association between high-frequency stimulant use and the combined outcomes of mortality and progression to Aids.
Over 1,000 HIV-positive men who have sex with men participating in the Multicentre AIDS Cohort Study (MACS) provided information for the study about methamphetamine, cocaine, crack cocaine, or ecstasy use. In addition, MACS researchers collected participant data of Aids-defining illnesses, CD4 cell counts, viral loads, and mortality. On average, participants stayed in the study for about eight and a half years, during which time they completed study visits every three months.
The researchers analysed participant data to look at the relationship between frequency of stimulant use and the likelihood of progressing to Aids or dying, while controlling for outside influences such as hepatitis C co-infection, high blood pressure, high cholesterol, depression, drinking, and smoking.
“We thought there would be this dose response relationship where people who had used more often, or reported use more frequently, would have more negative health outcomes. They would die faster, or they would progress to Aids or die faster,” explains Dr Adam Carrico, of department of community health systems, School of Nursing, University of California, San Francisco, and lead author of the paper. Unexpectedly, they didn’t find a significant association between stimulant use over time and mortality. “We found that when people are on HAART (highly active antiretroviral therapy), there are not mortality differences between stimulant users and non-users. Being a drug user didn’t mean that you died faster,” says Carrico.
When the researchers considered the combined outcome of progression to Aids or mortality, they did see evidence of what Carrico explained as a “modest” relationship. People who use stimulants more often (ie, reported stimulant use at more than half of their visits) displayed increased risk of progressing to Aids or dying by about 50%. To put this in perspective, this means that – if people who didn’t use stimulants had a 10% likelihood of dying or progressing to Aids during the study period – using stimulants frequently would increase this likelihood to 15%
Carrico explains that although modest, the effect is meaningful. “But it doesn’t mean that there’s this overwhelming effect of stimulant use. That everyone using stimulants is having negative outcomes. And it’s not the occasional user we’re worried about, it’s really people, for example, who meet criteria for treatment at Stonewall (San Francisco AIDS Foundation’s substance use treatment programme). Those are probably the folks that are really having negative health outcomes.”
Independent of drug use frequency, having a higher CD4 cell count when first beginning HAART was protective against mortality, researchers found. Starting HAART with a CD4 cell count below 200 was associated with over a four-fold increase in the odds of mortality. This was one of the take-away points from the study for Carrico, who notes that, “Using drugs doesn’t mean that you can’t manage your medications, engage in care and talk with your provider about how to get on and stay on HAART. And maximize your adherence. You can manage HIV and stimulant users can do it quite well. A lot of the story is about getting people who use drugs to start HAART. Once people are on treatment, they’re doing pretty well.”
Carrico doesn’t mean for people to conclude from the study’s findings that there are no consequences to stimulant use. “There are all sorts of reasons other than HIV to try to think about reducing or abstaining from stimulant use. Exploring ways to reduce or abstain from stimulants can be good for your overall health and well-being. Not just whether you die or develop Aids.”