Numerous factors, including unemployment, lack of health insurance and race, are associated with lower adherence to antiretroviral (ARV) treatment among people living with HIV in the United States.

Overall, the proportion of the HIV population who have been prescribed ARVs and adhere to their daily regimen at an optimal rate remains quite low, MPR reports.

Looking to estimate the rates of adherence to ARVs as well as the prevalence of drug resistance among people with HIV, investigators analyzed data from the Integrated Dataverse from the Symphony Health database and the Monogram/LabCorp Database. They period they analyzed ran from January 1, 2015, to September 30, 2017.

Published in AIDS and Behavior, the study measured adherence based on the percentage of days within a 12-month period that were covered by prescriptions filled by each individual.

On average, 72% of the days in that period were covered by ARVs among the nearly 170,000 people included in the analysis. Forty-five percent of the study cohort members were considered to have poor adherence because less than 80% of the days in the year were covered by ARVs, while 30% had suboptimal adherence (80% to just under 95% of days were covered) and just 25% had optimal adherence (95% or more days were covered).

In Southern states, 50% of the individuals had poor adherence to ARVs.

The study looked at nearly 96,000 samples provided for drug resistance testing and found that 31% showed evidence of resistance to ARVs. From state to state, the prevalence of drug resistance ranged from 20% to 54%. Out of the five states that had the highest prevalence of drug resistance, three of them had a rate of poor adherence to ARVs greater than 40%.

States with higher rates of drug resistance had a higher HIV prevalence rate. Having a higher prevalence of poor or suboptimal adherence to ARVs in any particular state was associated with a higher proportion of the population living with HIV, a lower HIV diagnosis rate, a higher HIV-related mortality rate and a lower rate of full suppression of the virus. Other factors associated with poor or suboptimal adherence to ARVs included lower education, poverty, unemployment, not being white and a lack of health insurance.

“This study is one of the first in the U.S. to provide a comprehensive understanding of the current status of adherence to ART], the prevalence of resistance to HIV drugs, social determinants of health that could be associated with poor or suboptimal adherence and ART resistance,” the authors concluded.

They added that what are known as the social determinants of health should be taken into consideration when selecting an ARV regimen. They further called for efforts to improve adherence and prevent the development of resistance—for example, through the use of single-tablet regimens that include ARVs that are known to protect against drug resistance emergence.

To read the MPR article, click here.

To read the study, click here