Trauma History Among Patients Receiving Methadone Maintenance Treatment: Sex Differences, Characteristics, and...

Most patients with opioid use disorder have experienced traumatic events; however, sex differences in trauma exposure, its timing, and its association with treatment outcomes remain unclear.

Of the 1194 patients admitted to a methadone maintenance treatment (1993-2025), 923 completed an intake questionnaire assessing traumatic events and their timing relative to substance use (before, during, "always", or "never"). Predictors of long-term retention were examined using Kaplan-Meier analyses and a Cox multivariate model.

Of 923 participants, 23.5% were female, and 74.4% reported trauma. Males (35.7%) more often reported trauma during substance use than females (27.6%), whereas females more frequently reported trauma occurring "always" (31.3%) than males (22.2%; p=0.024). Interpersonal trauma category was more prevalent in females (59% vs. 40.2%, p<0.001) with no differences in physical trauma (50.8%) and self-directed harm (38.8%). The age of opioid initiation was comparable between sexes but females were admitted to MMT younger. Substance use at admission was comparable between sexes, as were one-year and long-term retention (mean=9.8 years, 95% CI 9.1-10.6). Long-term retention between trauma timing groups and trauma categories were comparable, also when stratified by sex. Sex-specific differences emerged only when trauma type and timing were considered. Specifically rape history was associated with shorter retention among males but not females.

Traumatic experiences differed between sexes but were not associated with long-term retention and did not change the comparable outcomes between sexes. A bigger sample is needed to confirm the findings of shorter retention in male who experienced rape.