0135 Stress, Mindfulness, Perseverative Cognitions, and Sleep Quality: A Moderated Mediation Analysis

Introduction Psychological stress has previously been shown to be a predictor of poor sleep. Research indicates that pre-sleep cognitive arousal may mediate this relationship. Research has also suggested that mindfulness may improve sleep via its impact on perseverative cognitions. The purpose of the current study was to (1) examine the role of perseverative cognitions as a mediator in the stress-sleep relationship using both self-report and actigraphy measures of sleep and (2) determine whether the strength of this mediation is affected by one’s level of mindfulness. Methods Four weekday nights of concurrent actigraphy data were collected from 77 undergraduate students (86% female; 90% Hispanic; mean age 19.40 (2.07)). An online survey containing standardized measures of past-year stressful life events (ICSRLE), pre-sleep cognitive arousal (PSAS-Cognitive), sleep quality (PSQI) and trait mindfulness (MAAS) was also completed. Results Stress was correlated with poor sleep quality, both for self-report (r(77) = .36, p = .001) and actigraphy sleep fragmentation index (SFI; r(77) = .30, p = .004). Mediation/moderation analyses were conducted using Hayes’ PROCESS Macro V3.2 using 5,000 bootstrapped samples. Pre-sleep cognitive arousal did not significantly mediate this relationship for actigraph-based SFI (fully standardized indirect effect = -.05, SE = .08, 95% CI [-.206, .105]), but fully mediated this relationship for self-reported sleep quality (fully standardized indirect effect = .24, SE = .09, 95% CI [.076, .418]). Additionally, a moderated mediation analysis indicated that mindfulness significantly moderated this mediation (index of moderated mediation = -.004, SE = .002, 95% CI [-.0081, -.0001]. Conclusion Pre-sleep cognitive arousal emerged as a significant mediator between stressful life events and sleep quality for subjective, but not objective, sleep quality. For subjective sleep quality, this mediating effect varied as a function of mindfulness: the indirect effect of stressful life events on sleep quality through cognitive arousal was greater for individuals scoring low in trait mindfulness than for those who scored high. Mindfulness may therefore act as a buffer, attenuating the impact of stressful events on pre-sleep cognitive arousal. Support (If Any) N/A