HIV-positive injection drug users (IDUs) are just as likely to be alive 5 years after starting antiretroviral (ARV) therapy as non-IDU HIV-positive individuals, according to a report published in the August 6 issue of The Journal of the American Medical Association, coinciding with the start of the XVII International AIDS Conference in Mexico City. Julio Montaner, MD, of the University of British Columbia in Canada, and his study colleagues argue that these new data contradict the belief that IDUs with HIV receive fewer benefits from ARV therapy.

A number of reports have demonstrated that HIV-infected IDUs are less likely to respond favorably to ARV therapy, largely due to social instability and limited access to care. However, long-term evaluations of HIV treatment outcomes among IDUs compared with non-IDUs have not been available, notably in countries where ARV therapy is free.

Dr. Montaner’s group compared the rate of death among HIV-positive patients with and without a history of injection drug use initiating ARV therapy in British Columbia. Of the 3,116 patients followed for an average of five years, 915 were IDUs and 579 were women. Patients were about 34 years old when they started treatment.

During the study period, 622 patients died. Through seven years after the initiation of ARV treatment, the researchers found that the death rate from any cause was not significantly different between the two groups—26.5 percent among the IDUs and 21.6 percent among the non-IDUs.

Montaner’s group conducted an analysis that excluded deaths unlikely to be related to HIV, such as accidental overdoses, accidents and suicide. Accordingly, the IDUs were statistically more likely to die of such causes—21.1 percent of deaths among IDUs, compared with 9.7 percent among non-IDUs.

When accidental deaths were excluded from the analysis, death rates were similar between the two groups.

“Although our findings cannot be generalized outside of [this] cohort, as efforts to improve use of ARV therapy among IDUs expand, the fact that survival patterns were not significantly different between IDUs and non-IDUs should help to challenge the increasingly prevalent belief that IDUs may be markedly less likely to benefit from HIV treatment,” Montaner said.