HIV-positive people with a high degree of depressive symptoms, or who use stimulants on a weekly basis, are highly likely to go on and off antiretroviral (ARV) therapy or to stop treatment altogether, according to a study published November 24 in the Journal of Acquired Immune Deficiency Syndromes. The study’s authors suggest this behavior may help explain why people with psychological and substance use problems have worse health outcomes and faster HIV disease progression.
Researchers have noted the harmful affects of depression and substance abuse on the course of a person’s HIV disease since the earliest days of the epidemic. Taken together, the dozens of studies on these issues have demonstrated that people living with HIV and either depression or substance abuse have lower CD4 counts, higher viral loads, faster disease progression and higher mortality.
A number of factors can help explain poorer health outcomes in people with these conditions. People with psychological and substance abuse problems tend to be poorer, to have worse access to medical care, to be infected with diseases other than HIV, and to have poor treatment adherence when they do go on ARV drugs.
One potential contributing factor to poorer health that has not been well investigated is erratic use of ARVs. This is different than adherence, where the concern is how many doses over a period of time a person took correctly. Rather, ARV utilization explores whether a person purposefully stops taking medication and either remains off treatment or opts to use treatment only intermittently.
To explore this matter, Adam Carrico, PhD, from the University of California in San Francisco, and his colleagues analyzed data from a study that was initially designed to test an intervention to help HIV-positive people reduce behaviors that could pass on the virus to others.
Over 600 people participated in the study, which involved surveys and blood tests conducted every six months for 25 months. Roughly 18 percent of the participants reported at least weekly stimulant use, and 12 percent reported injecting drugs at least once in the previous year.
Ninety-four percent were on ARVs, and 33 percent had an undetectable viral load at the start of the study. Though an ideal adherence level is 95 percent of doses taken correctly, adherence averaged 88 percent across in the cohort.
Carrico and his colleagues defined ARV discontinuation as a person being on treatment and then going off for the remainder of the study. Intermittent ARV use was defined as going off treatment purposefully and then restarting treatment again—at least once.
The team found that depression and stimulant use both predicted erratic ARV use. People with high depressive scores at the outset of the study were 39 percent more likely to discontinue treatment altogether, while weekly stimulant users were more than two and a half times more likely to report intermittent discontinuations.
People who discontinued ARVs or who had intermittent utilization had much higher viral loads—and therefore a higher risk of HIV disease progression and CD4 cell loss—than people who remained on ARVs throughout the course of the study.
When accounting for poorer adherence and other factors, ARV discontinuation and intermittent utilization were both strongly predictive of a high viral load.
These study results suggest that “adjuvant mental health and substance abuse treatment will be needed to promote sustained ART utilization [and] achieve viral suppression,” the authors stated.
“In the context of HIV medical care, this will require implementation of rapid screening tools for depression and substance abuse and efficient methods for linkage to mental health and/or substance abuse treatment,” they concluded.
