Dropout Rates and Factors Associated with Adherence to Opioid Agonist Treatment Among Adults with Opioid Use Disorder at Sekou Toure Regional Referral Hospital, Mwanza, Tanzania

Allen Rweyendera^1,2Tusherahma Tuli^1*Greyson Gwahula¹YACINTER Vedastus¹Raymond Maziku¹Peter Chilipweli^3*Kiyeti A Hauli⁴

• ¹School of Medicine,, Catholic University of Health and Allied Sciences (CUHAS), Bugando, Tanzania
• ²Development of Research and Consultancy, Community Health and Development Foundation (CHADF), Mwanza,, Tanzania
• ³Department of Community Medicine, School of Public Health,, Catholic University of Health and Allied Sciences (CUHAS), Bugando, Tanzania
• ⁴Department of Psychiatry, Bugando Medical Center, Catholic University of Health and Allied Sciences (CUHAS), Bugando, Tanzania

Background: Opioid use remains a significant global public health concern, with approximately 60 million people using opioids and 39.5 million living with opioid use disorders. Opioid agonist treatment (OAT), particularly methadone, is an effective intervention for opioid dependence, though retention remains problematic worldwide. This study aimed to determine the dropout rate and identify factors influencing adherence to OAT among patients at Sekou Toure Regional Referral Hospital (SRRH) in Mwanza, Tanzania. Methods: A mixed-method design combining a retrospective cohort and cross-sectional approach was used. Retrospective data were extracted from records of patients enrolled from February 2018 to March 2024. A cross-sectional survey was conducted from September to November 2024 among 223 systematically selected patients. Data analysis included descriptive statistics and Chi-square tests, with significance set at p < 0.05. Results: The dropout rate was 37.9%. Most dropouts were men (97.4%), consistent with the predominantly male patient population. Nearly half of the dropouts (47.7%) had only primary education. Adherence was influenced by personal motivations such as improving health (27.8%) and maintaining sobriety (27.4%), social support (25.6% reported none), and psychological distress (38.1% reported severe symptoms). Perceived treatment effectiveness varied, with 46.6% rating OAT as effective or very effective. Conclusion: The high dropout rate highlights the need for targeted interventions focused on men, individuals with lower education levels, and patients lacking social support. Strengthening the treatment environment, enhancing psychological support, and improving communication about OAT effectiveness may improve retention. Further research is needed to understand barriers to confidence in OAT and perceptions of treatment ineffectiveness.