Factors affecting optimal adherence to antiretroviral therapy and viral suppression amongst HIV-infected prisoners in South Ethiopia: a comparative cross-sectional study

Background Maintaining optimal adherence and viral suppression in people living with HIV (PLWH) is essential to ensure both preventative and therapeutic benefits of antiretroviral therapy (ART). Prisoners bear a particularly high burden of HIV infection and are highly likely to transmit to others during and after incarceration. However, the level of treatment adherence and viral suppression in incarcerated populations in low-income countries is unknown. This study aimed to determine factors affecting optimal adherence to antiretroviral therapy and viral suppression amongst HIV-infected prisoners in South Ethiopia. Methods A comparative cross-sectional study was conducted between June 1, 2019 and May 31, 2020 to compare the level of adherence and viral suppression between incarcerated and non-incarcerated PLWH. Patient information including demographic, socio-economic, behavioral, and incarceration-related characteristics were collected using a structured questionnaire. Medication adherence was assessed according to self-report and pharmacy refill. Plasma viral load measurements undertaken within the study period were prospectively extracted to determine viral suppression. Univariate and multivariate logistic and fractional regression models were used to analyse data. Results Seventy-four inmates living with HIV (ILWH) and 296 non-incarcerated PLWH participated in the study. While ILWH had a significantly higher pharmacy refill adherence compared to non-incarcerated PLWH (89 vs 75%), they had a slightly lower dose adherence (81% vs 83%). The prevalence of viral non-suppression was also slightly higher in ILWH (6.0%; 95% confidence interval (CI): 1.7-14.6%) compared to non-incarcerated PLWH (4.5%; 95%CI: 2.4-7.5%). Overall, missing ART appointments, dissatisfaction with ART services, inability to comply with a specified medication schedule, and types of methods used to monitor the schedule (e.g., news time on radio/TV or other social cues) were significantly associated with non-adherence according to self-report. In ILWH specifically, accessing ART services from a hospital, inability to properly attend clinic appointments, depressive symptoms, and lack of social support predicted NA. Viral non-suppression was significantly higher in males, people of age 31to 35 years and in those who experienced social stigma, regardless of their incarceration status. Conclusions Sub-optimal dose adherence and viral suppression are generally higher in HIV-infected prisoners in South Ethiopia compared to their non-incarcerated counterparts. A multitude of factors were found to be responsible for this requiring multilevel intervention strategies focusing on the specific needs of prisoners.