Gender differences in access to methadone maintenance therapy in a Canadian setting.

INTRODUCTION AND AIMS: Methadone maintenance therapy (MMT) is an evidence-based treatment for opioid addiction. While gender differences in MMT pharmacokinetics, drug use patterns and clinical profiles have been previously described, few studies have compared rates of MMT use among community-recruited samples of persons who inject drugs (PWID).

DESIGN AND METHODS: The present study used prospective cohorts of PWID followed between May 1996 and May 2013 in Vancouver, British Columbia, Canada. We investigated potential factors associated with time to methadone initiation using Cox proportional hazards modelling. Stratified analyses were used to examine for gender differences in rates of MMT enrolment.

RESULTS: Overall, 1848 baseline methadone-naïve PWID were included in the study, among whom 595 (32%) were female. In an adjusted model, male gender was independently associated with increased time to MMT initiation and an overall lower rate of enrolment [adjusted relative hazard = 0.74 (95% confidence interval: 0.65-0.85)]. Among both female and male PWID, Caucasian ethnicity and daily injection heroin use were associated with decreased time to methadone initiation, while in females, pregnancy was also associated with more rapid initiation.

DISCUSSION AND CONCLUSIONS: These data highlight gender differences in methadone use among a population of community-recruited PWID. While factors associated with methadone use were similar between genders, rates of use were lower among male PWID, highlighting the need to consider gender when designing strategies to improve recruitment into MMT. [Bach P, Milloy M-J, Nguyen P, Koehn J, Guillemi S, Kerr T, Wood E. Gender differences in access to methadone maintenance therapy in a Canadian setting. Drug Alcohol Rev 2015;34:503-7].