Title: Antiretroviral therapy adherence patterns, virological suppression, and emergence of drug resistance: A nested case-control study from Uganda and South Africa.
Authors: Tyagi A, Tong Y, Rabideau DJ, Reynolds Z, De Oliveira T, Lessells R, Amanyire G, Orrell C, Asiimwe S, Chimukangara B, Giandhari J, Pillay S, Haberer JE, Siedner MJ; META Study Investigators. .
Journal: Antivir Ther.,27(5):13596535221114822. doi: 10.1177/13596535221114822: ()
Abstract
Background: Relationships between distinct antiretroviral therapy (ART) adherence patterns and risk of drug resistance are not well understood.
Methods: We conducted a nested case-control analysis within a longitudinal cohort study of individuals initiating efavirenz-based ART. Primary outcomes of interest, measured at 6 and 12 months after treatment initiation, were: 1) virologic suppression, 2) virologic failure with resistance, and 3) virologic failure without resistance. Our primary exposure of interest was ART adherence, measured over the 6 months before each visit with electronic pill monitors, and categorized in three ways: 1) 6 months average adherence; 2) running adherence, defined as the proportion of days with average adherence over 9 days of less than or equal to 10%, 20%, and 30%; and 3) number of 3-, 7-, and 28-day treatment gaps in the prior 6 months.
Results: We analyzed data from 166 individuals (107 had virologic failure during observation and 59 had virologic suppression at 6 and 12 months). Average adherence was higher among those with virologic suppression (median 83%, IQR 58-96%) versus those with virologic failure with resistance (median 35%, IQR 20-77%, pairwise P < 0.01) and those with virologic failure without resistance (median 21%, IQR 2-54%, pairwise P < 0.01). Although treatment gaps generally predicted virologic failure (P < 0.01), they did not differentiate failure with and without drug resistance (P > 0.6).
Conclusions: Average adherence patterns, but not the assessed frequency of treatment gaps, differentiated failure with versus without drug resistance among individuals initiating efavirenz-based ART. Future work should explore adherence-resistance relationships for integrase inhibitor-based regimens.
Download: Full text paper
Citation: Tyagi A, Tong Y, Rabideau DJ, Reynolds Z, De Oliveira T, Lessells R, Amanyire G, Orrell C, Asiimwe S, Chimukangara B, Giandhari J, Pillay S, Haberer JE, Siedner MJ; META Study Investigators. . Antiretroviral therapy adherence patterns, virological suppression, and emergence of drug resistance: A nested case-control study from Uganda and South Africa. Antivir Ther.,27(5):13596535221114822. doi: 10.1177/13596535221114822: ().