Predictors of patient retention in methadone maintenance treatment.

Abstract

This study sought to determine whether select pretreatment demographic and in-treatment clinical variables predict premature treatment discharge at 6 and 12 months among patients receiving methadone maintenance treatment (MMT). Data were abstracted from electronic medical records for 1,644 patients with an average age of 34.7 years (SD = 11.06) admitted to 26 MMT programs located throughout the United States from 2009 to 2011. Patients were studied through retrospective chart review for 12 months or until treatment discharge. Premature discharge at 6- and 12-month intervals were the dependent variables, analyzed in logistic regressions. Clinical predictor variables included average methadone dosage (mg/d) and urinalysis drug screen (UDS) findings for opioids and various nonopioid substances at intake and 6 months. Pretreatment demographic variables included gender, race/ethnicity, employment status, marital status, payment method, and age at admission. UDS findings positive (UDS+) for cocaine at intake and 6 months were found to be independent predictors of premature discharge at 12 months. UDS+ for opioids at 6 months was also an independent predictor of premature discharge at 12 months. Higher average daily methadone dosages were found to predict retention at both 6 and 12 months. Significant demographic predictors of premature discharge at 6 months included Hispanic ethnicity, unemployment, and marital status. At 12 months, male gender, younger age, and self-pay were found to predict premature discharge. Select demographic characteristics may be less important as predictors of outcome after patients have been in treatment beyond a minimum period of time, while others may become more important later on in treatment.