Antiretroviral hair levels objectively quantify drug exposure over time and predict virologic responses. We assessed the acceptability and feasibility of collecting small hair samples in a rural Kenyan cohort. Ninety-five percentage of participants (354/373) donated hair. Although median self-reported adherence was 100% (interquartile range, 96%–100%), a wide range of hair concentrations likely indicates overestimation of self-reported adherence and the advantages of a pharmacologic adherence measure. Higher nevirapine hair concentrations observed in women and older adults require further study to unravel behavioral versus pharmacokinetic contributors. In resource-limited settings, hair antiretroviral levels may serve as a low-cost quantitative biomarker of adherence.
*Division of HIV/AIDS, Department of Medicine, University of California, San Francisco, San Francisco, CA;
†Mfangano Island Research Group, Organic Health Response, Homa Bay County, Kenya;
‡Microclinic International (MCI), San Francisco, CA;
§Department of Surgery, UCSF East Bay, Oakland, CA;
‖Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA;
¶Department of Environmental Science, Policy & Management, University of California, Berkeley, Berkeley, CA;
#Center for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya;
**Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA; and
††Family AIDS Care & Education Services, Kisumu, Kenya.
Correspondence to: Monica Gandhi, MD, MPH, Division of HIV/AIDS, Department of Medicine, University of California, San Francisco, 995 Potrero Avenue, 4th floor, San Francisco, CA 94143 (e-mail: firstname.lastname@example.org).
M.D.H. and C.R.S. have contributed equally to this work.
Supported by the National Institute of Allergy and Infectious Diseases (NIAID)/National Institutes of Health (NIH) (RO1 AI098472 to M.G.), a Clinical Research Fellowship grant from the Doris Duke Charitable Foundation (M.D.H.), and a UCSF School of Medicine Dean's research fellowship (C.R.S.). Additional funding support was provided to the Organic Health Response and Microclinic International by Google, Inc. via the Tides Foundation, the Mulago Foundation, the Rise Up Foundation, the Horace W Goldsmith Foundation, the Craigslist Foundation, and Professor Ray Lifchez of UC Berkeley.
The remaining authors have no funding or conflicts of interest to disclose.
Received October 24, 2013
Accepted January 09, 2014