Musanje, KhamisiKamya, R. MosesKasujja, RoscoVanderplasschen, WouterSinclair, Deborah L.Baluku, M. MartinOdokonyero, F. RaymondNamisi, P. CharlesMukisa, JohnWhite, G. RossCamlin, S. Carol2025-06-242025-06-242024-03-062325-9582Online ISSN: 2325-9582https://doi.org/10.1177/23259582241236http://hdl.handle.net/20.500.12280/3206Adherence to antiretroviral therapy (ART) is lower in adolescents with HIV (AWH) than in any other age group, partly due to self-regulatory challenges during development. Mindfulness and acceptance training have been shown to support psychological flexibility, a self-regulatory skill that potentially improves adolescent adherence to medication. We assessed the effect of weekly group-based mindfulness and acceptance training sessions on ART adherence among older adolescents (15–19 years) in Kampala, Uganda. One hundred and twenty-two AWH (median age 17, range 15–19 years, 57% female) receiving care at a public health facility in Kampala were randomized 1:1 to receive 4 weekly 90-min group sessions facilitated by experienced trainers or standard-of-care ART services. The training involved (Session 1) clarifying values, (Session 2) skillfully relating to thoughts, (Session 3) allowing and becoming aware of experiences non-judgmentally, and (Session 4) exploring life through trial and error. At baseline, postintervention, and 3-month follow-up, psychological flexibility was measured using the Avoidance and Fusion Questionnaire for Youth (AFQ-Y8), and self-reported ART adherence was assessed using the Morisky Medication Adherence Scale (MMAS-8). At baseline, the intervention and standard-of-care arms had similar psychological flexibility (AFQ-Y8 score:15.45 ± 0.82; 15.74 ± 0.84) and ART adherence (MMAS-8 score: 5.32 ± 0.24; 5.13 ± 0.23). Retention through the study was moderate (71%). Completion of mindfulness and acceptance training was associated with a significant reduction in psychological inflexibility at the 3-month follow-up (AFQ-Y8 score: 12.63 ± 1.06; 14.05 ± 1.07, P = .006). However, no significant differences were observed in self-reported adherence to ART at the 3-month follow-up (MMAS-8 score: 5.43 ± 0.23; 4.90 ± 0.33, P = .522). Group-based mindfulness and acceptance training improved psychological flexibility in this population of adolescents on ART in Uganda but did not significantly improve ART adherence.enHIVAdherenceMindfulnessMental healthHealth outcomesPsychological flexibilityArticle