Assessing the impact of public funding in alleviating participant reduction and improving the retention rate in methadone maintenance treatment clinics in Taiwan: an interrupted time series analysis

Abstract

Background: Given the steady decline in patient numbers at methadone maintenance treatment (MMT) clinics in Taiwan since 2013, the government initiated Patients' Medical Expenditure Supplements (PMES) in January 2019 and the MMT Clinics Accessibility Maintenance Program (MCAM) in September 2019. This study aims to evaluate the impact of the PMES and MCAM on the enrollment and retention of patients attending MMT clinics and whether there are differential impacts on MMT clinics with different capacities.

Methods: The monthly average number of daily participants and 3-month retention rate from 2013 to 2019 were extracted from MMT databases and subjected to single interrupted time series analysis. Pre-PMES (from February 2013 to December 2018) was contrasted with post-PMES, either from January 2019 to December 2019 for clinics funded solely by the PMES or from January 2019 to August 2019 for clinics with additional MCAM. Pre-MCAM (from January 2019 to August 2019) was contrasted with post-MCAM (from September 2019 to December 2019). Based on the monthly average number of daily patients in 2018, each MMT clinic was categorized as tiny (1-50), small (51-100), medium (101-150), or large (151-700) for subsequent stratification analysis.

Results: In terms of participant numbers after the PMES intervention, a level elevation and slope increase were detected in the clinics at every scale except medium in MMT clinics funded solely by PMES. In MMT clinics with subsequent MCAM, a level elevation was only detected in small-scale clinics, and a slope increase in the participant numbers was detected in tiny- and small-scale clinics. The slope decrease was also detected in medium-scale clinics. In terms of the 3-month retention rate, a post-PMES level elevation was detected at almost every scale of the clinics, and a slope decrease was detected in the overall and tiny-scale clinics for both types of clinics.

Conclusions: Supplementing the cost of a broad treatment repertoire enhances the enrollment of people with heroin use in MMTs. Further funding of human resources is vital for MMT clinics to keep up with the increasing numbers of participants and their retention.

Keywords: Accessibility maintenance; Enrolling; Medical expenditure supplement; Methadone maintenance treatment; Public funding; Retention.