Investigation of Repeat Client Drop-Out and Re-Enrolment Cycles in Fourteen Methadone Maintenance Treatment Clinics in Guangdong, China.
OBJECTIVE
Client adherence is vital for effective methadone maintenance treatment (MMT). This study explores the pattern and associated factors of client adherence, drop-out and re-enrolment in the Chinese MMT programme over the period of 2006-2013.


METHODS
This retrospective study was conducted in 14 MMT clinics in Guangdong Province, China. We employed Kaplan-Meier survival analysis to estimate the rates of drop-out and re-enrolment of MMT clients and multivariate Cox regression to identify associated factors.


RESULTS
Among 1,512 study participants, 79% have experienced 'drop-out' during the 7-year study period. However, 82% 'dropped-out' clients resumed treatment at a later time. Low education level (junior high or below versus otherwise, HR = 1.21, 1.05-1.40), low methadone dosage in the first treatment episode (<50 ml versus ≥50 ml, HR = 1.84, 1.64-2.06) and higher proportion of positive urine test (≥50% versus<50%, HR = 3.72, 3.30-4.20) during the first treatment episode were strong predictors of subsequent drop-outs of the participants. Among the 'dropped-out' clients, being female (HR = 1.40, 1.23-1.60), being married (HR = 1.19, 1.09-1.30), and having a higher proportion of positive urine tests in the first treatment episode (≥50% versus<50%, HR = 1.35, 1.20-1.51) had greater likelihood of subsequent re-enrolment in MMT. Clients receiving lower methadone dosage (first treatment episode <50 ml versus ≥50 ml, HR = 1.12, 1.03-1.23; the last intake before drop-out <50 ml versus ≥50 ml, HR = 1.16, 1.04-1.30) were also more likely to re-enrol.


CONCLUSIONS
Persistent cycling in-and-out of clients in MMT programmes is common. Insufficient dosage and higher proportion of positive urine samples in the first treatment episode are the key determinants for subsequent client drop-out and re-enrolment. Interventions should target clients in their early stage of treatment to improve retention in the long term.
Sun Yat-sen Centre for Migrant Health Policy, Sun Yat-sen University, #74, Zhongshan Road II, Guangzhou, 510080, P.R. China; The Kirby Institute, University of New South Wales, Sydney, NSW, Australia.
Lei
L
Zhang
Sun Yat-sen Centre for Migrant Health Policy, Sun Yat-sen University, #74, Zhongshan Road II, Guangzhou, 510080, P.R. China; Faculty of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, #74, Zhongshan Road II, Guangzhou, 510080, P.R. China.
Xia
X
Zou
Sun Yat-sen Centre for Migrant Health Policy, Sun Yat-sen University, #74, Zhongshan Road II, Guangzhou, 510080, P.R. China; Faculty of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, #74, Zhongshan Road II, Guangzhou, 510080, P.R. China; Office of Medical Science, Sun Yat-sen University, Guangzhou, P. R. China.
Di
D
Zhang
Sun Yat-sen Centre for Migrant Health Policy, Sun Yat-sen University, #74, Zhongshan Road II, Guangzhou, 510080, P.R. China; Faculty of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, #74, Zhongshan Road II, Guangzhou, 510080, P.R. China.
Xiaoling
X
Li
Sun Yat-sen Centre for Migrant Health Policy, Sun Yat-sen University, #74, Zhongshan Road II, Guangzhou, 510080, P.R. China; Faculty of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, #74, Zhongshan Road II, Guangzhou, 510080, P.R. China.
Peizhen
P
Zhao
Sun Yat-sen Centre for Migrant Health Policy, Sun Yat-sen University, #74, Zhongshan Road II, Guangzhou, 510080, P.R. China; Faculty of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, #74, Zhongshan Road II, Guangzhou, 510080, P.R. China.
Li
L
Ling
D000328:Adult; D002681:China; D005260:Female; D006556:Heroin Dependence / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008691:Methadone / Q000627:therapeutic use*; D008875:Middle Aged; D009294:Narcotics / Q000627:therapeutic use*; D058850:Opiate Substitution Treatment; D010352:Patient Dropouts; D012189:Retrospective Studies; D016320:Substance Abuse Treatment Centers; D016896:Treatment Outcome; D055815:Young Adult
D009294:Narcotics; D008691:Methadone