0392 Exploring Crew Recuperation After Deployment: Preliminary Results

Abstract Introduction Crewmembers on United States Navy ships often spend months deployed away from their homeports. During these deployments, their lives are characterized by long hours of shift work, sleep deprivation, circadian misalignment, with few days off and periods of high stress. Little is known about how Sailors recuperate upon returning to homeport. Methods In a naturalistic longitudinal approach using Gen3 ŌURA rings, we monitored the sleep of 67 Sailors (20 to 59 years of age; 71.6% males; 73.1% enlisted personnel) from three destroyers during and after an ~8-month deployment. Sailor sleep during the entire deployment was assessed by descriptive analysis. Mixed-effects models were used to estimate differences in sleep characteristics across two months (one before and one after returning to homeport). Results Over the entire deployment, Sailors slept on average 6.44±0.78 hours/day (80% slept < 7hrs/day). Approximately 91% of the Sailors spent < 25% of their major sleep episode in deep sleep; ~41% spent < 20% in REM sleep. The month post-return was characterized by increased average respiratory rate (difference=0.1breaths/minute, p=0.021), average heart rate (difference=1.7bpm, p=0.011), lowest heart rate (difference=1.1bpm, p=0.045), but no statistically significant differences in daily sleep duration (p=0.241), sleep architecture (light sleep, p=0.506; deep sleep, p=0.188; REM sleep, p=0.154), heart rate variability (p=0.096), sleep latency (p=0.339), and sleep efficiency (p=0.166). Conclusion We did not identify systematic and substantive differences in sleep immediately following deployment compared to the period preceding the end of the deployment. Although we cannot establish the causal factors leading to this pattern of results, the issue of recuperation from chronic sleep deprivation after returning to homeport is important in terms of Sailor operational performance, well-being, and health. Thus, the Navy should educate Sailors on the importance of both deployment and homeport sleep hygiene. We recommend that a) Sailor recuperation be studied further and that b) the Navy should develop evidence-based recuperation guidelines. Support (if any) The views expressed in this research are those of the authors and do not necessarily reflect the official policy or position of the Department of the Navy, Department of Defense, or the U.S. Government. This study was funded by the Defense Suicide Prevention Office (DSPO).