0291 Sleepiness and Subjective Well-Being as Predictors of Functional Impairment Among Fasting Adults in Nigeria

Abstract Introduction Voluntary religious fasting, prevalent across many African settings, may impair sleep due to circadian rhythm disruptions and altered meal timing, with downstream effects on daytime functioning. Fasting may predispose individuals to increased sleepiness and altered psychological well-being, both established predictors of functional impairment. However, sleep during fasting remains understudied in African populations, where unique sociocultural contexts limit our understanding of these relationships. This cross-sectional study examined the independent and interactive effects of sleepiness and subjective psychological well-being on functional impairment among fasting adults in Nigeria. We hypothesized that higher sleepiness would predict greater impairment, higher subjective psychological well-being would predict lower impairment, and that well-being would moderate the sleepiness-impairment relationship. Methods Participants (N = 138; Mean age = 31.14, SD = 11.08; 57% female), fasting for at least two weeks, completed an online survey hosted on Google Forms, which included the Epworth Sleepiness Scale, WHO-5 Well-Being Index, and PROMIS Sleep-Related Impairment Scale. Hierarchical linear regression tested the main effects of sleepiness and subjective psychological well-being, and the moderating effects of sleepiness and subjective well-being on sleep-related impairment. Results The main effects model explained significant variance in functional impairment (R² = .196, p < .001). Higher daytime sleepiness strongly predicted greater impairment (β = .58, p < .001), while higher psychological well-being independently predicted lower impairment (β = -.26, p = .022). Contrary to hypotheses, the sleepiness and well-being interaction was non-significant (p = .954), indicating that psychological well-being does not buffer the impairing effects of daytime sleepiness. Conclusion Daytime sleepiness and psychological well-being contribute independently rather than interactively to functional impairment during fasting. These findings suggest that fasting individuals experiencing daytime impairment may benefit from interventions that directly address sleep deficits alongside efforts to promote better psychological well-being. Given the widespread practice of religious fasting globally, understanding these independent pathways has important implications for promoting health and productivity during fasting periods. Future research should investigate whether sleepiness and well-being operate through distinct mechanisms to improve the health of diverse fasting populations. Support (if any) None