@entity5198 Concentration in Hair Samples Is a Strong Predictor of Virologic Suppression in a Prospective Cohort of XXXX -Infected @entity1 .

@entity1 @entity16333 @entity645 @entity5198
UNASSIGNED: Effective antiretroviral (ARV) therapy depends on adequate drug exposure, yet methods to assess ARV exposure are limited. Concentrations of ARV in hair are the product of steady-state pharmacokinetics factors and longitudinal adherence. We investigated @entity5198 ( @entity16333 ) concentrations in hair as a predictor of treatment response in @entity1 receiving ARVs. In @entity1 of the @entity1 's Interagency @entity645 Study, who reported @entity16333 use for >1 month from 2003-2008, @entity16333 concentrations in hair were measured via liquid-chromatography-tandem mass-spectrometry. The outcome was virologic suppression (plasma @entity645 RNA below assay threshold) at the time of hair sampling and the primary predictor was @entity5198 concentration categorized into quartiles. We controlled for age, race/ethnicity, pre-treatment @entity645 RNA, CD4 cell count, and self-reported adherence over the 6-month visit interval (categorized  <= 74%, 75%-94% or >=  95%). We also assessed the relation of @entity16333 concentration with changes in hepatic transaminase levels via multivariate random intercept logistic regression and linear regression analyses. 271 @entity1 contributed 1089 @entity1 -visits to the analysis (median 3 of semi-annual visits). Viral suppression was least frequent in concentration quartile 1 (86/178 (48.3%)) and increased in higher quartiles (to 158/204 (77.5%) for quartile 4). The odds of viral suppression in the highest concentration quartile were 9.17 times (95% CI 3.2-26, P < 0.0001) those in the lowest. African-American race was associated with lower rates of virologic suppression independent of @entity16333 hair concentration. @entity16333 concentration was not significantly associated with patterns of serum transaminases. Concentration of @entity16333 in hair was a strong independent predictor of virologic suppression in @entity1 taking @entity16333 , stronger than self-reported adherence, but did not appear to be strongly predictive of hepatotoxicity.
