A benchmark of near-perfect adherence (≥95%) to antiretroviral therapy (ART) is often cited as necessary for HIV viral suppression. However, given newer, more effective ART medications, the threshold for viral suppression may be lower. We estimated the minimum ART adherence level necessary to achieve viral suppression.
The Patient-centered HIV Care Model demonstration project.
Adherence to ART was calculated using the proportion of days covered measure for the 365-day period before each viral load test result, and grouped into 5 categories (<50%, 50% to <80%, 80% to <85%, 85% to <90%, and ≥90%). Binomial regression analyses were conducted to determine factors associated with viral suppression (HIV RNA <200 copies/mL); demographics, proportion of days covered category, and ART regimen type were explanatory variables. Generalized estimating equations with an exchangeable working correlation matrix accounted for correlation within subjects. In addition, probit regression models were used to estimate adherence levels required to achieve viral suppression in 90% of HIV viral load tests.
The adjusted odds of viral suppression did not differ between persons with an adherence level of 80% to <85% or 85% to <90% and those with an adherence level of ≥90%. In addition, the overall estimated adherence level necessary to achieve viral suppression in 90% of viral load tests was 82% and varied by regimen type; integrase inhibitor- and nonnucleoside reverse transcriptase inhibitor-based regimens achieved 90% viral suppression with adherence levels of 75% and 78%, respectively.
The ART adherence level necessary to reach HIV viral suppression may be lower than previously thought and may be regimen-dependent.
aDivision of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, GA;
bHealth Analytics, Research, and Reporting Department, Walgreen Co., Deerfield, IL;
cDepartment of Biostatistics and Epidemiology, University of North Texas Health Science Center, Fort Worth, TX;
dDepartment of Pharmacotherapy, University of North Texas Health Science Center System College of Pharmacy, Fort Worth, TX;
eDepartment of Health, Research, Informatics, and Technology, ICF, Atlanta, GA; and
fPatient Care and Advocacy Department, Walgreen Co., Deerfield, IL.
Correspondence to: Kathy K. Byrd, MD, MPH, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, 1600 Clifton Road, MS E-45, Atlanta, GA 30329 (e-mail: firstname.lastname@example.org).
Supported by the U.S. Department of Health and Human Services Secretary's Minority AIDS Initiative fund and the Centers for Disease Control and Prevention through a co-operative agreement [grant number NU65PS004275] with the University of North Texas Health Science Center System College of Pharmacy. Walgreen Co., provided all services in-kind.
J.G.H., R.H., H.K., and A.D. report that they were employees of Walgreen Co., during the conduct of this study. The remaining authors have no conflicts of interest to disclose.
The findings and conclusions of this analysis are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.
Members of Patient-Centered HIV Care Model Team are listed in Appendix1.
Received March 28, 2019
Accepted July 08, 2019