Davis Kristin M, Shields Grant S, Slavich George M, Zilioli Samuele
Department of Psychology, Wayne State University, Detroit, MI, USA.
Department of Psychological Science, University of Arkansas, Fayetteville, AR, USA.
Ann Behav Med. 2025 Jan 4;59(1). doi: 10.1093/abm/kaaf013.
Although sleep disparities contribute to racial health disparities, little is known about factors affecting sleep among African Americans. One such factor may be positive affect, which could impact sleep directly (direct effect hypothesis) or indirectly by buffering the effects of stress (stress buffering hypothesis).
We tested the direct effect and stress buffering effects of positive affect on sleep at three levels (day, week, trait) in a sample of 210 older African American adults, ranging in age from 50 to 89 years old.
Daily positive affect, perceived stress, sleep quality, and sleep duration were collected for five consecutive days. Multilevel modeling was used to test the direct and stress buffering hypotheses both within-person (day level) and between-persons (week level). Trait positive affect, past five-year stress severity, and global sleep quality were assessed cross-sectionally. Regression was used to test the direct and stress buffering hypotheses at the trait level.
In line with the direct effect hypothesis, higher week-level positive affect predicted better sleep quality and sleep duration. Day-level positive affect was not significantly associated with daily sleep quality or daily sleep duration. Higher trait positive affect predicted better global sleep quality. However, neither day-level perceived stress nor past five-year stress severity significantly interacted with positive affect measures for any sleep outcome; no interaction effect was observed on week-level sleep duration. Positive affect and perceived stress interacted at the week level to predict sleep quality, but not in the hypothesized direction.
We found support for the direct effect hypothesis at the week- and trait-levels, but not at the day level. In contrast, we found no support for the stress buffering hypothesis.
尽管睡眠差异导致了种族健康差异，但对于影响非裔美国人睡眠的因素却知之甚少。积极情绪可能是其中一个因素，它可能直接影响睡眠（直接效应假说），也可能通过缓冲压力的影响间接影响睡眠（压力缓冲假说）。
我们在210名年龄在50至89岁之间的老年非裔美国成年人样本中，测试了积极情绪在三个层面（日、周、特质）对睡眠的直接效应和压力缓冲效应。
连续五天收集每日的积极情绪、感知压力、睡眠质量和睡眠时间。采用多水平模型在个体内部（日层面）和个体之间（周层面）测试直接效应和压力缓冲假说。对特质积极情绪、过去五年的压力严重程度和整体睡眠质量进行横断面评估。采用回归分析在特质层面测试直接效应和压力缓冲假说。
与直接效应假说一致，较高的周层面积极情绪预示着更好的睡眠质量和睡眠时间。日层面的积极情绪与每日睡眠质量或每日睡眠时间没有显著关联。较高的特质积极情绪预示着更好的整体睡眠质量。然而，日层面的感知压力和过去五年的压力严重程度与任何睡眠结果的积极情绪测量指标均未产生显著交互作用；在周层面睡眠时间上未观察到交互作用。积极情绪和感知压力在周层面相互作用以预测睡眠质量，但并非按照假设的方向。
我们在周层面和特质层面发现了对直接效应假说的支持，但在日层面没有。相比之下，我们没有发现对压力缓冲假说的支持。
