More than 40 percent of injection drug users with HIV who are eligible for the highly active antiretroviral therapy fail to undergo the treatment, according to a study conducted by the Bloomberg School of Public Health. The HAART regimen, or "drug cocktail," is a combination of several antiretroviral drugs that can dramatically reduce the levels of HIV in the body and slow the progression to AIDS. The study, which appears in the September issue of the journal AIDS, suggests that injection drug use is a major impediment to initiating HAART therapy, while methadone addiction treatment among men, health insurance and access to regular health care were factors associated with increased HAART use.
"Injection drug users directly or indirectly account for nearly half of all the people infected with HIV in the United States each year, and they are a population that could certainly benefit from HAART use. In addition to making people with HIV feel better, HAART has also been shown to make them less infectious to others by reducing their viral load, so there is a real benefit to the public," says lead author David D. Celentano, professor of epidemiology at the Bloomberg School.
"Over the years, we've seen an increase in the number of injection drug users undergoing HAART, but a large number still do not use the therapy. It is important to understand the factors involved in why drug users choose or do not choose this therapy. Our study examines some of the factors that contribute to HAART use among injection drug users with HIV," Celentano says.
For the study, researchers examined 528 HIV-infected injection drug users living in Baltimore between 1996 and 1999. All the participants were originally part of a larger long-term study of AIDS and injection drug users known as AIDS Links to Intravenous Experience, or ALIVE; in addition, all had a CD4 cell count making them eligible to begin HAART treatment according to guidelines established by the International AIDS Society and U.S. panels.
The participants were interviewed and examined every six months. Researchers also collected demographic data and information on current drug use, sexual behavior, utilization of health care, AIDS symptoms and use of specific antiretroviral drugs.
Overall, nearly one-third of the injection drug users eligible for antiretroviral treatment never received it. According to the study, injection drug use was strongly associated with not instituting HAART. Participants who stated they injected drugs consistently were more than 58 percent less likely to initiate HAART, and intermittent drug users were 20 percent less likely to use HAART. The study also shows that men enrolled in methadone treatment for drug addiction were 80 percent more likely to enroll in HAART than those who were not on methadone; however, there was no increase in HAART initiation among women using methadone.
Having health care and regular access to care outside of the study also was associated strongly with increased HAART initiation. Participants with health insurance were four times more likely to initiate HAART treatment than those without insurance, and those who received some other form of antiretroviral treatment also were more likely to start HAART treatment.
"By identifying the factors associated with HAART initiation among injection drug users, we can develop better public health policies to treat this population," Celentano says.
Other authors are Noya Galai, Ajay K. Sethi, Nina G. Shah, Steffanie A. Strathdee, David Vlahov and Joel E. Gallant.
The study was funded by grants from the National
Institute on Drug Abuse.