Assessment of prevalence and factors associated with continual substance use among patients using Methadone in medically assisted treatment clinics in Dar es salaam, Tanzania

Abstract

ABSTRACT Background: Substance use is a global concern, affecting millions. Methadone maintenance therapy (MMT) is effective for treating opioid addiction, but concurrent illicit drug use remains an issue among MMT patients. In Tanzania, Medically Assisted Treatment (MAT) has been in use since 2011, yet it faces challenges with concurrent substance use, impacting treatment outcomes. Objective: To assess the prevalence and factors associated with continued substance use among patients using methadone in MAT centres (MNH, Mwananyamala RRH, and Temeke RRH) in Dar es Salaam. Methods and Materials: A cross-sectional study was conducted at three MAT clinics in Dar es Salaam: Muhimbili National Hospital, Temeke Regional Referral Hospital, and Mwananyamala Regional Referral Hospital. The study included 461 participants selected through systematic sampling from the MAT database at each hospital. Data were collected using electronic questionnaires programmed with Open Data Kit (ODK) and administered via smartphones/tablets. Data cleaning and analysis were performed using STATA version 17. Descriptive analysis provided insights into the prevalence and patterns of continued substance use. The Modified Poisson model assessed factors associated with the outcome, with covariates having a p-value < 0.2 included in a multivariate analysis. Statistical significance was determined by a p-value < 0.05. Results: The prevalence of continued substance use among methadone patients in MAT clinics was 52% (n=239). The most reported substances were cannabis (72%), heroin (30.1%), and alcohol (22.6%). There was a higher prevalence at Temeke RRH (65.2%) than at Muhimbili National Hospital (57.3%) and Mwananyamala RRH (36.1%). Modified Poisson model revealed that easy access to drugs in residential areas, stigma, loneliness, depression perceived insufficiency of methadone dosage and having friends using substances were significant factors associated with continual substance use. Sources of the substance used included easy drug access in residential areas (59.3%) and pharmacies 87% where prescription medicines, such as Diazepam (65.9%,) and Tramadol (48% )were obtained. Conclusion: The study highlights a significant prevalence of continued substance use among methadone patients in MAT clinics in Dar es Salaam. Factors such as easy access to drugs, stigma, loneliness, depression, perceived insufficiency of methadone dosage, and social circles involving substance use are crucial in influencing continued substance use. Addressing these factors through comprehensive strategies is essential to improve treatment outcomes and reduce concurrent substance use among methadone patients in Tanzania.