LAUSR

Opioid use disorder (OUD) is a chronic relapsing disorder with a high overdose death rate. In OUD, sleep and circadian disruptions are highly prevalent, interfere with retention in opioid maintenance treatment (OMT) and increase relapse. Growing evidence suggests a link between sleep/circadian disruptions and dopaminergic (DA) signaling which accounts for addictive properties of drugs of abuse. The current study investigated rest-activity rhythm in Methadone and Buprenorphine-maintained patients and how it relates to DA changes in patients. To access rest-activity rhythm, twenty-five OUD patients (9 Females; age 44.34±11.97; 60% White, 32% Black; 18 Methadone; 7 Buprenorphine) and thirty-four age, sex, race and BMI-matched healthy controls wore wrist accelerometers for one-week and completed questionnaires for sleep and chronotype. Among OUD patients, sixteen of them completed [11C]NNC112 and [11C]raclopride PET scans for the assessments of D1R and D2R availability, respectively. Negative mood was accessed as secondary outcomes. Our preliminary data showed that compared to healthy participants, OUD patients undergoing OMT reported greater sleep problems and showed greater sleep irregularity measured by actigraphy, but no differences in other parameters such as sleep duration, rhythm timing or physical activity. Among patients, greater eveningness and irregularity were associated with higher level of negative mood including depression and anxiety. There is a tendency of a positive correlation between later phase and greater D1 receptor availability and a negative association between sleep irregularity and D2 receptor availability. Our finding suggests that a link between altered rest-activity rhythm and DA signaling in OUD patients. Circadian/sleep interventions that regulate rest-activity rhythm might benefit mood improvement and promote OUD recovery by normalizing DA transmission.