1108 Prior-night Sleep Predicts Next-day Symptoms over Ten Days Among Military Personnel with Sleep Problems

Abstract Introduction Insufficient and disturbed sleep are highly prevalent and associated with adverse consequences in the U.S. military. The purpose of this study was to employ remote monitoring/ecological momentary assessment methods to test the hypothesis that prior-night sleep is associated with next-day subjective symptoms among military personnel. Methods Participants (N=270) with sleep problems were recruited from two military treatment facilities and completed an intensive ten-day remote monitoring assessment. Prior night sleep was measured using standardized sleep diaries and a commercial wearable sleep tracker (Fitbit Inspire 2). Next-day symptoms were measured using twice-daily symptom surveys (i.e., 20 surveys over ten days). Individual items assessed subjective cognition, energy level, and mood using an “I feel tired” format and scored from 0-4. To determine the lagged impact of prior-night sleep on next-day symptoms, a total of 40 mixed models (MMs) were developed. Individual prior-night sleep diary (total sleep time [TST], sleep efficiency [SE], and sleep quality [QUAL]) and Fitbit (TST, SE) parameters were entered as independent variables, and individual daytime symptoms (feeling alert, clear-headed, refreshed, fatigued, happy, sad, stressed, and relaxed) were entered as dependent variables. All models controlled for age and sex. The Benjamini-Hochberg procedure for correcting false discovery rate (BH-FDR) method was used to correct for multiple comparisons. Results Lagged MM analyses revealed that all prior-night sleep diary variables were significantly associated with next-day symptoms (all ps< 0.001 with df=2081) over ten days. Specifically, prior-night sleep diary parameters (TST, SE, QUAL) were positively associated with next-day feeling alert, clear-headed, refreshed, happy, and relaxed; and negatively associated with next-day feeling fatigued, sad, and stressed. Prior-night Fitbit sleep parameters were significantly associated with most next-day symptoms (largest p=0.023 with df=1956). Specifically, Fitbit TST and SE were positively associated with next-day feeling clear-headed, refreshed, happy, and relaxed and negatively associated with next-day fatigue. Fitbit TST was negatively associated with next-day stress. Conclusion Among military personnel with sleep problems, prior-night sleep predicts next-day subjective cognition, energy level, and mood over ten days. Future research should employ remote monitoring approaches to predict treatment response and deliver personalized care to improve sleep and daytime symptoms. Support (if any) DoD W81XWH1990006 (via Medical Technology Enterprise Consortium)