Assessment of HIV antiretroviral therapy adherence by measuring drug concentrations in hair among children in rural Uganda

Abstract

Current tools for measuring medication adherence have significant limitations, especially among pediatric populations. We conducted a prospective observational study to assess the use of antiretroviral (ARV) drug levels in hair for evaluating antiretroviral therapy (ART) adherence among HIV-infected children in rural Uganda. Three-day caregiver recall, 30-day visual analog scale (VAS), Medication Event Monitoring System (MEMS), and unannounced pill counts and liquid formulation weights (UPC) were collected monthly over a one-year period. Hair samples were collected quarterly and analyzed for nevirapine (NVP) levels, and plasma HIV RNA levels were collected every six months. Among children with at least one hair sample collected, we used univariable random intercept linear regression models to compare log transformed NVP concentrations with each adherence measure, and the child's age, sex, and CD4 count percentage (CD4%). One hundred and twenty-one children aged 2–10 years were enrolled in the study; 74 (61%) provided at least one hair sample, and the mean number of hair samples collected per child was 1.9 (standard deviation [SD] 1.0). Three-day caregiver recall, VAS, and MEMS were found to be positively associated with increasing NVP concentration in hair, although associations were not statistically significant. UPC was found to have a nonsignificant negative association with increasing hair NVP concentration. In conclusion, NVP drug concentrations in hair were found to have nonsignificant, although generally positive, associations with other adherence measures in a cohort of HIV-infected children in Uganda. Hair collection in this population proved challenging, suggesting the need for community education and buy-in with the introduction of novel methodologies.

Keywords:

• antiretroviral therapy
• human immunodeficiency virus
• adherence
• children
• Uganda

Acknowledgments

The authors would like to thank the study participants, as well as the following study staff: Nneka Emenyonu, Georgina Nakafero, Jenniffer Owomuhangi, Sarah Namwanje, Ambrose Mugyenyi, Allen Kiconco, Andrew Mugumemushabe, Dan Mwehire, Mathias Orimwesiga, Constance Katabazi, Teddy Komuhangi, and Henry Kizito.

Additional information

Funding

This study was supported by the National Institutes of Health (NIMH) [K23MH087228] to J.H., [R21MH083306] to J.H., J.K., and D.N. and National Institute of Allergy and Infectious Diseases (NIAID) [grant number RO1AI098472] to M.G. Partial funding for this work was provided by NIH/NIAID (American Recovery and Reinvestment Act Funds) [grant number 3R01AI065233-05S2].