Outcome of Enhanced Adherence Counselling on Viral Load Suppression Among HIV Clients with Unsuppressed Viral Load in a Tertiary Hospital in Southwest Nigeria: A Retrospective Cohort Study (Published)
Virological failure among people living with HIV (PLHIV) persists despite advances in antiretroviral therapy (ART). World Health Organization (WHO) guidelines recommend Enhanced Adherence Counselling (EAC) to restore adherence and promote viral re-suppression. However, evaluation of post-EAC outcomes in routine programmatic settings is frequently confounded by attrition in repeat viral load testing and inappropriate statistical handling of missing data. To evaluate viral re-suppression, changes in viral load, and factors associated with outcomes following EAC among HIV clients with unsuppressed viral load at the Obafemi Awolowo University Teaching Hospital Complex (OAUTHC), Osun State, Nigeria, using rigorous paired longitudinal analyses and distinguishing between retested clients and the total enrolled cohort. A retrospective cohort study was conducted reviewing records of 149 clients with unsuppressed viral load (≥1000 copies/mL) enrolled in EAC between January 2019 and December 2023. Paired log10 viral load changes were evaluated using Wilcoxon signed-rank tests and paired t-tests restricted to clients with documented follow-up testing. Binary viral suppression (<1000 copies/mL vs. ≥1000 copies/mL) was analyzed using Fisher’s exact tests, Risk Ratios (RR), and multivariable binary logistic regression. Sensitivity analysis (missing follow-up = unsuppressed) was conducted to estimate population-level impact. Of 149 enrolled clients, repeat testing was documented for 67 (44.9%) at 3 months, 41 (27.5%) at 6 months, and 24 (16.0%) at 12 months. Among clients with a documented repeat result, viral suppression (<1000 copies/mL) was achieved by 45/67 (67.2%) at 3 months, 34/41 (82.9%) at 6 months, and 17/24 (70.8%) at 12 months. Relative to the full enrolled cohort (N = 149), the proportion of original clients with documented re-suppression was 30.2% (45/149), 22.8% (34/149), and 11.4% (17/149). In conservative sensitivity analysis (missing = unsuppressed), non-suppression rates were 69.8%, 77.2%, and 88.6%. Log10 viral load decreased significantly among retested clients from baseline to 6 months (mean difference = -2.30 log10, 95% CI: -2.72 to -1.88, p < .001; Z = -5.24, p < .001) and 12 months (mean difference = -2.03 log10, 95% CI: -2.65 to -1.41, p < .001; Z = -4.01, p < .001). Multivariable logistic regression among retested clients at 3 months (n = 67) identified interruption of care (adjusted OR = 0.11, 95% CI: 0.03–0.41, p = .001) and tuberculosis (adjusted OR = 0.06, 95% CI: 0.01–0.54, p = .012) as independent negative predictors of suppression. EAC significantly reduced viral load among clients who returned for testing, with conditional re-suppression meeting WHO benchmarks at 6 and 12 months. However, overall program effectiveness was severely compromised by low repeat testing uptake and care interruptions. Nurse-led retention strategies, tracking of missing appointments, and routine paired monitoring are critical.
Keywords: adherence barriers, antiretroviral therapy, enhanced adherence counselling, missing follow-up, paired longitudinal analysis, viral load suppression