Factors associated with drug resistance mutations among antiretroviral therapy-experienced adolescents living with HIV in South Rift Valley, Kenya

Abstract: Background: Antiretroviral therapy (ART) has significantly improved survival among people living with human immunodeficiency virus (PLHIV), yet drug resistance mutations (DRMs) continue to threaten treatment outcomes globally. Adolescents remain particularly vulnerable to DRMs due to biological, behavioural and structural factors. However, little is known about the factors associated with DRMs in the South Rift Valley (SRV) of Kenya. Aim: To assess factors associated with DRMs among ART-experienced adolescents in SRV. Setting: Eighty-two HIV clinics located in Nandi, Kericho, Bomet and Narok counties in Kenya’s SRV region. Methods: A retrospective cohort study was conducted among 226 ART-experienced adolescents aged 10–19 years with virologic failure, selected through simple random sampling. Plasma samples were genotyped to identify HIVDRMs using the Stanford HIV Drug Resistance database. Demographic, clinical and behavioural information was obtained from medical records and questionnaires. Descriptive statistics, Chi-square tests and logistic regression were performed to determine factors associated with DRMs. Results: The median age was 17 years (IQR: 15–18); 51.3% was male and 65% was orphans. Bivariate analysis identified several factors significantly associated with DRMs: ART duration (p = 0.030), enhanced adherence counselling (EAC) sessions (p = 0.001), ART regimen type (p = 0.001), CD4 count (p = 0.030), caregiver occupation (p = 0.029), and orphan status (p = 0.049). Conclusion: Longer ART duration, multiple EAC sessions and use of non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimens were associated with DRMs. These findings underscore the need for strengthened adherence support, early regimen optimisation and targeted interventions for adolescents at higher risk of resistance. Contribution: The study provides evidence to guide clinical and policy strategies aimed at improving ART outcomes among adolescents in Kenya.