Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, Maryland, USA.
Human Genetics Branch, National Institute of Mental Health Intramural Research Program, Bethesda, Maryland, USA.
Am J Med Genet B Neuropsychiatr Genet. 2021 Mar;186(2):113-121. doi: 10.1002/ajmg.b.32840. Epub 2021 Mar 1.
Sleep is essential to the human brain and is regulated by genetics with many features conserved across species. Sleep is also influenced by health and environmental factors; identifying replicable genetic variants contributing to sleep may require accounting for these factors. We examined how stress and mood disorder contribute to sleep and impact its heritability. Our sample included 326 Amish/Mennonite individuals with a lifestyle with limited technological interferences with sleep. Sleep measures included Pittsburgh Sleep Quality Index (PSQI), bedtime, wake time, and time to sleep onset. Current stress level, cumulative life stressors, and mood disorder were also evaluated. We estimated the heritability of sleep features and examined the impact of current stress, lifetime stress, mood diagnosis on sleep quality. The results showed current stress, lifetime stress, and mood disorder were independently associated with PSQI score (p < .05). Heritability of PSQI was low (0-0.23) before and after accounting for stress and mood. Bedtime, wake time, and minutes to sleep time did show significant heritability at 0.44, 0.42, and 0.29. However, after adjusting for shared environment, only heritability of wake time remained significant. Sleep is affected by environmental stress and mental health factors even in a society with limited technological interference with sleep. Wake time may be a more biological marker of sleep as compared to the evening measures which are more influenced by other household members. Accounting for nongenetic and partially genetic determinants of sleep particularly stress and mood disorder is likely important for improving the precision of genetic studies of sleep.
睡眠对人类大脑至关重要，其受到遗传因素的调控，在不同物种中具有许多保守特征。睡眠也受到健康和环境因素的影响；确定导致睡眠的可复制遗传变异可能需要考虑这些因素。我们研究了压力和情绪障碍如何影响睡眠并影响其遗传性。我们的样本包括 326 名阿米什/门诺派个体，他们的生活方式受到限制，很少受到科技对睡眠的干扰。睡眠测量包括匹兹堡睡眠质量指数（PSQI）、就寝时间、醒来时间和入睡时间。还评估了当前的压力水平、累积生活压力源和情绪障碍。我们估计了睡眠特征的遗传性，并研究了当前压力、终生压力、情绪障碍对睡眠质量的影响。结果表明，当前压力、终生压力和情绪障碍与 PSQI 评分独立相关（p <.05）。在考虑压力和情绪后，PSQI 的遗传性较低（0-0.23）。然而，在调整共享环境后，只有醒来时间的遗传性仍然显著。即使在一个受到科技对睡眠干扰有限的社会中，睡眠也会受到环境压力和心理健康因素的影响。与受其他家庭成员影响更大的晚上测量相比，醒来时间可能是睡眠的更生物学标志物。考虑到睡眠的非遗传和部分遗传决定因素，特别是压力和情绪障碍，对于提高睡眠遗传研究的准确性可能很重要。
