Adherence has improved by 50% in most populations.
Though it continues to be a key challenge preventing scientists and clinicians from curtailing the HIV/AIDS epidemic, patient adherence to HIV/AIDS medication regiment is improving dramatically.
More than 43,000 HIV patients across 14 states who were receiving Medicare benefits were assessed by researchers led by Ira B Wilson, MD, chair of the Health Service Policy and Practice Department at Brown University School of Public Health.
Among those patients, the median duration of continuing to take antiretroviral drugs increased by nearly 50% in the 9-year period between 2001 and 2010.
“These differences represent a tremendous, very real benefit,” Wilson said. “This represents a lot of people who are not dying and not infecting others.”
According to the study, reasons for the increasing duration included less toxic antiretroviral (ART) drugs and the reduction over time in the number of pills HIV patients were likely to be taking. Researchers found that patients taking only one pill per day had a 29% lower risk of discontinuing their medication than those taking 6 pills per day.
In addition, about half of the HIV care sites in the US include adherence counseling as part of the routine regimen, the study reported. The level of participation in the adherence counseling programs, however, is only about 20%.
Race, sex, and geography affected the adherence and duration results as well.
“These disparities are substantial in size, and did not improve over time in our data,” the study said, which strengthened “the case that disparities in medication adherence are an important driver of disparities in the health outcomes of persons with chronic conditions.”
African Americans and women were reported “to present lower levels of adherence possibly because of limited resources and restricted access to care,” researchers wrote. The differences between lower adherence levels in southern states, such as Texas and Louisiana, as compared with northern states like New York and California, could reflect reduced access to Medicaid benefits in Texas and Louisiana.
The study defined persistence as continuous treatment with a prescribed medication. The median duration for the study’s participants was not high, researchers noted. From 2004 to 2006, it reached 35.4 months. However, that duration for the use of ACE/ARB blood pressure medication in a non-HIV control group over the same period was 25.5 month.
The study noted that the improvement in persistence for such control medications was greater when patients were already taking ART. That suggested “there could be something about taking ART or about HIV care settings that improves persistence with other medications,” researchers wrote.
The consequences of discontinuing ART treatment include a viral rebound, viral resistance that may limit medication options in the future, and ongoing damage to the immune system by HIV, the study said.
The increase in treatment persistence among HIV patients “is still not optimal,” said Bora Youn, graduate student in the Brown Department of Health Services, Policy and Practice. said in a press release. “There is a lot of room for further improvement.”
The inability to prove whether persistent medication compliance resulted in better outcomes was a limitation, the study said. Also, the results cannot be generalized to non-Medicaid populations, the study added.