A comparative study of opioid substitution therapy utilisation among opioid-dependent men and women

Introduction and Aims: Few population-based studies have examined differences in opioid substitution therapy (OST) treatment utilisation between men and women. Using a population of opioid-dependent people in New South Wales, Australia, first-episode and long-term OST treatment utilisation profiles were compared between men and women, differentiating between treatment initiation in the community and in custody. Design and Methods: Retrospective data linkage study using records of new OST entrants (2001-2010) and custody episodes (2000-2012). First OST treatment episode and overall treatment utilisation characteristics were compared between men and women initiating treatment in the community or in custody. Treatment retention was evaluated at 3, 6, 9 and 12 months after first commencing OST and overall, as the median proportion of follow-up time spent in treatment. Results: There were 15600 new OST entrants in the cohort-10930 were men (70.1%) and 4670 women (29.9%); 12584 (80.7%) initiated treatment in the community and 3016 (19.3%) in custody. More men initiated OST in custody (24.0% vs. 8.3%, P<0.001) and only received OST in custody (57.5% vs. 41.8%, P<0.001). Women were retained longer in their first OST treatment episode at all four time points in both treatment settings and in treatment overall (community: 46.6% vs. 39.1%, P<0.001; custody: 41.3% vs. 30.8%, P<0.001). Discussion and Conclusions: There are a number of key differences in OST treatment utilisation profiles between men and women. Whereas men commonly initiate and only receive OST in custody, treatment retention is higher among women, independent of the setting treatment is initiated.