A26 SLEEP, Volume 44, Abstract Supplement, 2021 A. Basic and Translational Sleep and Circadian Science VII. Physiology and S2 (p=.876), but BRS signifcantly increased following 8 weeks of intervention at S3 compared to S1 (p=0.033) and S2 (p=0.037). There was also a signifcant decrease in BPMax across the three stays during EPII (p<.001). There was no signifcant decrease in EPII BPMax be- tween S1 and S2 (p=.325), but BPMax signifcantly decreased in S3 compared to S1 (p<0.001) and S2 (p=0.002). Conclusion: While we are still blind to condition, both conditions are considered active as they both involve stabilizing the sleep period using sleep hygiene. These preliminary data suggest that stabilization of sleep timing and possibly duration, has a positive impact on BP regulation. Support (if any): NIH (R01HL125379 to Dr. Janet Mullington), Harvard Catalyst, Harvard Clinical and Translational Science Center (UL1TR001102). 062 SEX DIFFERENCES IN SLOW WAVE SLEEP FOLLOWING EVENING BINGE ALCOHOL CONSUMPTION Ian Greenlund, 1 Jeremy Bigalke, 1 Anne Tikkanen, 1 Jennifer Nicevski, 1 Carl Smoot, 2 Jason Carter 1 1 Montana State University, 2 Michigan Technological University Introduction: Binge alcohol consumption alters normal sleep archi- tecture, often via increased slow wave sleep (SWS) and decreased rapid eye movement (REM) sleep. Women may be more susceptible to the sedative efects of alcohol during blood alcohol content (BAC) decrease as they report higher subjective sleepiness scores prior to bedtime. The purpose of the present study was to examine changes in SWS between men and women following binge alcohol consumption and determine the relation between BAC change at lights out and sub- sequent sleep architecture. Methods: Twenty-three participants (11 men, 12 women) between the ages of 21–45 years were tested twice, once after evening binge alcohol consumption and once after fuid control (randomized, cross- over design). The alcohol dose was based on body weight and sex (1g/ kg in men, 0.85g/kg in women) and served as a 4–5 drink equivalent consumed over two hours. Breath alcohol content (BrAC) was moni- tored in 15-minute increments from frst drink consumption to lights out. Overnight polysomnography (PSG) was recorded in each indi- vidual and scored by a board-certifed sleep physician. Statistical ana- lysis consisted of repeated measures ANOVA and Pearson correlation (p>0.05). Results: Age (24±4 vs. 26±6 years) and BMI (27±4 vs. 27±4 kg/ m2) were similar between men and women. Peak BrAC (0.10±0.02% vs. 0.10±0.02%) and percent change (-19±11% vs. -19±11%) in BrAC from peak to lights out were also similar between the sexes. Peak BrAC was signifcantly correlated to the percentage of SWS in women (r=-0.71; p=0.01), but not men (r=-0.25; p=0.45). Similarly, the percent change in BrAC from peak to lights out was signifcantly correlated to the percentage of SWS in women (r=-0.66; p=0.02), but not men (r=-0.40; p=0.22). The SWS and REM latencies were not associated with either peak or lights out BrAC in both men and women. Conclusion: Peak BrAC, and the rate of BrAC clearance prior to lights out, appear to impact SWS diferently in men and women. Specifcally, women appear to have more SWS in response to high BrAC than their male counterparts, suggesting a stronger depressor impact with re- gards to SWS in women. Support (if any): National Institutes of Health (AA-024892; U54GM115371; P20GM103474). 063 DIFFERENTIAL IMPACT OF SLEEP DURATION ON NOCTURNAL BLOOD PRESSURE DIPPING BETWEEN MEN AND WOMEN Jeremy Bigalke, 1 Ian Greenlund, 1 Jennifer Nicevski, 1 Neha John- Henderson, 1 Jason Carter 1 1 Montana State University Introduction: There is growing evidence that poor sleep may have a greater impact on the development of cardiovascular complications in women compared to men. However, most studies that have evaluated the impact of sex on sleep insufciencies and blood pressure (BP) have not utilized ambulatory BP, and often rely more heavily on subjective sleep diaries as opposed to objective sleep assessment. The purpose of this study was to examine the impact of sex on the relationship between objectively measured sleep and nocturnal BP dipping. We hypothe- sized that poor sleep would be associated with decreased nocturnal BP dipping, and that this association would be stronger in women. Methods: Total sleep time (TST) and sleep efciency (SE) were moni- tored in ffty adults (31 men, 19 women; 36±3 years; 26±1 kg/m2) util- izing wrist actigraphy monitoring over the course of 5–14 days (Avg: 10±0 days). On a separate occasion, participants underwent a 24-hour ambulatory BP recording session. Independent samples T-tests were used to compare characteristics between sexes. Partial correlations controlling for age and BMI were utilized to probe relationships be- tween sleep and nocturnal BP dipping. Results: TST and SE were not diferent between sexes. However, women exhibited reduced mean arterial pressure (MAP: 86±1 vs. 90±1 mmHg, P=0.026) compared to men. Partial correlation revealed a signifcant relationship between TST and the magnitude of noc- turnal MAP dipping in the sample population (R = 0.460, P<0.001). When stratifed by sex, this signifcant relationship persisted in men (R = 0.610, P<0.001), but not women (R = 0.108, P>0.05). In contrast, no relationship was observed between SE and nocturnal MAP dipping (R = -0.052, P>0.05) for the sample population. Similarly, SE did not correlate with nocturnal MAP dipping in men (R = -0.080, P>0.05) or women (R = 0.045, P>0.05). Conclusion: Contrary to our initial hypothesis, our results dem- onstrate that actigraphy-based TST is associated with nocturnal BP dipping in healthy men, but not women. This suggests a relation be- tween impaired nocturnal BP regulation and habitual sleep duration, potentially predisposing men to an increased overall risk for cardiovas- cular complications. Support (if any): National Institutes of Health (HL-098676 and HL-122919) 064 HIGHER RESTING HRV ENHANCES PROTECTIVE EFFECTS OF SELF-REPORTED RESILIENCE AGAINST THE IMPACT OF POOR SLEEP QUALITY ON PTSS Alisa Huskey, 1 Daniel Taylor, 1 Bruce Friedman 2 1 University of Arizona, 2 Virginia Polytechnic Institute and State University Introduction: Poor sleep quality is a well-established risk for posttraumatic symptoms (PTSS; Casement et al., 2012; Germain et al., 2004; 2005). Conversely, self-reported resilience is a well-established protective factor against PTSS (Mealer et al., 2012; Wrenn et al., 2011) and has also been shown to moderate the negative impacts of stressful life events on sleep quality (Li et al., 2019). Fewer studies have Downloaded from https://academic.oup.com/sleep/article/44/Supplement_2/A26/6260078 by guest on 25 June 2022