Missed Doses, Treatment Interruptions and Self-Rated Adherence among Adults on Antiretroviral Therapy in Ibadan, Nigeria: A Cross-Sectional Study

Background: Consistent antiretroviral therapy (ART) adherence is essential for viral suppression and progress towards the UNAIDS 95-95-95 targets, but a single global self-rating may not identify specific missed doses or treatment interruptions. Aims: To measure missed doses and treatment interruptions among adults receiving ART in Ibadan, examine their correlates, and assess whether a global self-rating reflects reported medication-taking behaviour. Study Design: A cross-sectional study, reported in accordance with STROBE. Place and Duration of Study: HIV clinic, Adeoyo Specialist Hospital, Ring Road, Ibadan, Oyo State, Nigeria, from March to July 2025. Methodology: In this cross-sectional study, 100 adults receiving ART were selected using systematic sampling and completed an interviewer-administered questionnaire about missed doses during the previous seven days, dose timing, treatment interruptions lasting more than two days, and a four-level global adherence rating. Prevalences are reported with Wilson 95% confidence intervals (CIs); associations were assessed using Fisher’s exact or chi-square tests, Spearman correlation, and logistic regression. Results: Mean age was 36.7 ± 8.0 years and 52% were male. Nineteen percent (95% CI 12.5–27.8) reported no missed doses in the previous seven days, 58% missed at least two doses, 47% (37.5–56.7) reported an interruption lasting more than two days, and 38% (29.1–47.8) always took doses on time. Only 45% (35.6–54.8) rated adherence as good or excellent. The global rating was not significantly correlated with missed doses (Spearman ρ = 0.10, P = .31) or interruptions (ρ = −0.03, P = .79); 20 of 23 participants rating adherence excellent reported at least one missed dose. No factor was significantly associated with interruption after adjustment (overall model P = .37); the unadjusted association with smoking was not statistically significant after adjustment (adjusted OR 2.03, 95% CI 0.84–4.93; P = .12). Conclusion: Missed doses and treatment interruptions were commonly reported, and a single global self-rating did not reliably reflect reported behaviour. HIV programmes should use specific, recall-bounded questions and assess barriers to continuity of treatment. Because viral load was not measured, this study cannot determine whether reported behaviours were associated with virological failure; larger studies combining behavioural questions with viral load and other adherence measures are warranted.