0147 The Moderating Role of Rest-Activity Rhythms in Early PTSD Symptoms After Hospitalization for a Stroke/Transient Ischemic Attack

Abstract Introduction Posttraumatic stress disorder (PTSD) symptoms are common after stroke/transient ischemic attack (TIA), and post-stroke distress is related to worse functional recovery and shorter sleep. Hospitalization and early recovery are marked by less differentiation between active and rest periods, but the role of rest-activity rhythms in subsequent PTSD remains unclear. We examined whether more robust rest-activity rhythms were related to less severe PTSD symptoms and whether they weakened the association between acute in-hospital distress and later PTSD. Methods Patients admitted to the hospital with stroke/TIA symptoms completed the Acute Stress Disorder Scale (ASDS) in-hospital and wore GENEActiv wrist accelerometers for up to 45 days (N= 394, 58.3% female). PTSD symptoms were assessed 1 month post-discharge using the PTSD Checklist for DSM-5 (0–80), keyed to their medical event. We derived relative amplitude (RA) from raw accelerometry in participants with ≥5 days of ≥18 hours/day of valid wear (M[SD]= 30.8[8.9] days). RA reflects the average contrast in activity between the least active 5 and most active 10 hours; higher (0–1) indicates more robust rhythms. Linear regressions tested associations between RA and 1-month PTSD symptoms, adjusting for ASDS to account for initial distress, and then additionally controlling for age, sex, stroke severity (NIH Stroke Scale), discharge location (home vs. inpatient rehab/other), and medical comorbidities (Charlson Comorbidity Index). We also tested whether RA moderated the prospective influence of ASDS on later PTSD with and without covariates. Results Higher RA was associated with lower 1-month PTSD symptoms, β= -1.46, p=.02, adjusting for ASDS. RA also moderated the prospective link from ASDS to PTSD: 1 SD higher RA attenuated PTSD symptoms by 1.93 points (p<.01), and this interaction effect persisted when all covariates were included (β= -2.05, p<.01). No covariates independently related to PTSD symptoms. Conclusion Less robust rest-activity rhythms early after hospitalization for suspected stroke are related to greater early PTSD symptoms and may amplify the impact of initial distress. Interventions enhancing rest-activity rhythms (e.g., light therapy, consistent routines) may reduce PTSD risk following medical events. Ongoing work will test whether these patterns persist at 6 months post-discharge. Support (if any) NHLBI R01-HL141494, R01-HL132347; SRSF Career Development Award