1045 Sex Differences in Sleep Deficiency and Treatment Outcomes Among Individuals Receiving Methadone for Opioid Use Disorder

Abstract Introduction Sleep deficiency is common among individuals with opioid use disorder (OUD) and may contribute to psychiatric distress, substance use, and poor retention in treatment. Sex-specific differences in sleep health and their relationship to OUD outcomes remain poorly understood. We sought to characterize sex differences in sleep deficiency, psychological symptoms, and treatment outcomes in a large community-based opioid treatment program (OTP). Methods Validated measures of sleep—including the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS), the first two items of the Cambridge-Hopkins Restless Legs Syndrome questionnaire (CH-RLSq), and the STOP Questionnaire—were administered to all patients at a Connecticut OTP in August 2023. Psychological symptoms were assessed using the 24-item Behavior and Symptom Identification Scale (BASIS-24). Chart-derived variables included methadone dose, number of take-home days, and treatment duration. One-year outcomes assessed in August 2024 included retention, urine toxicology, and mortality. Group differences by sex were evaluated using t-tests and chi-square tests. Results Methadone dose (81.62 mg men vs. 81.9 mg women, p = 0.87), take-home days (12.55 vs. 13.13, p = 0.31), and treatment duration (7.12 vs. 7.02 years, p = 0.74) did not differ by sex. Women reported significantly poorer sleep: higher PSQI scores (8.18 vs. 6.89, p < 0.0001), greater insomnia severity (ISI 9.27 vs. 7.67, p = 0.0001), and more restless-legs symptoms (0.68 vs. 0.52, p = 0.0011). STOP and ESS scores did not differ. Women also demonstrated higher BASIS-24 Depression (1.13 vs. 0.87, p < 0.001). Over one year, women were more likely to test positive for benzodiazepines (30.0% vs. 24.8%, p = 0.046), whereas men were more likely to test positive for fentanyl (34.99% vs. 28.48%, p = 0.0185). Treatment retention was similar (p = 0.86). Thirteen participants died (9 women, 4 men). Conclusion In this large community-based cohort of patients receiving methadone for OUD, women exhibited markedly poorer sleep quality and more depressive symptoms than men despite comparable treatment duration and retention. Over one year, more women tested positive for benzodiazepines, while more men tested positive for fentanyl. Support (if any)