School of Medicine, South China University of Technology, Guangzhou, 510006, Guangdong Province, China.
Guangdong Mental Health Center, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510080, Guangdong Province, China.
BMC Psychiatry. 2022 Feb 24;22(1):147. doi: 10.1186/s12888-022-03738-0.
Subjective cognitive decline (SCD) may be the early screening signal to distinguish susceptible population with Alzheimer's disease (AD) and mild cognitive impairment (MCI). Subjective cognitive complaints (SCCs) have been proved strongly associated with SCD. This study aimed to explore the association between sleep duration and SCCs in the Chinese elderly.
We conducted a cross-sectional study involving 688 participants aged 60 years and older in Guangdong Province, China. SCCs were assessed by the Subjective Cognitive Decline questionnaire 9 (SCD-Q9), which contained 9 items with two dimensions, including the overall memory function and time comparison (OMTC) and daily activity ability (DAA). Restricted cubic splines and generalized additive model (GAM) were used to fit the association between sleep duration and SCD-Q9 score.
There were significant U-shaped associations between sleep duration and overall score of SCD-Q9 (EDF = 3.842, P < 0.001), as well as the OMTC dimension (EDF = 4.471, P < 0.001) in the age- and gender-adjusted GAM. The lowest points on the overall score of SCD-Q9 and OMTC score were observed in those sleeping 8 h per night. After further adjusting for other demographic characteristics, lifestyle behaviors, hypertension and diabetes, the U-shaped associations between sleep duration and the overall score of SCD-Q9 (EDF = 3.575, P = 0.004), sleep duration and the OMTC score (EDF = 4.478, P = 0.010) were still found. The daily activity ability (DAA) score was also non-linear associated with sleep duration both in the age- and gender-adjusted GAM (EDF = 2.314, P < 0.001) and further adjusted GAM (EDF = 2.080, P = 0.010).
Both longer sleep duration (> 8 h) and shorter duration (< 8 h) were linked to worse SCCs. Future studies should explore the protective effect of managing sleep duration on SCD and its progression to dementia.
主观认知下降（SCD）可能是区分阿尔茨海默病（AD）和轻度认知障碍（MCI）易感人群的早期筛查信号。主观认知主诉（SCCs）已被证明与 SCD 密切相关。本研究旨在探讨中国老年人睡眠时长与 SCCs 之间的关系。
我们进行了一项横断面研究，纳入了中国广东省 688 名 60 岁及以上的参与者。SCCs 通过主观认知下降问卷 9（SCD-Q9）进行评估，该问卷包含 9 个项目，分为两个维度，包括整体记忆功能和时间比较（OMTC）和日常活动能力（DAA）。受限立方样条和广义加性模型（GAM）用于拟合睡眠时长与 SCD-Q9 评分之间的关联。
在年龄和性别调整后的 GAM 中，睡眠时长与 SCD-Q9 总分（EDF=3.842，P<0.001）以及 OMTC 维度（EDF=4.471，P<0.001）之间存在显著的 U 型关联。SCD-Q9 总分和 OMTC 得分最低的是每晚睡眠 8 小时的人群。进一步调整其他人口统计学特征、生活方式行为、高血压和糖尿病后，睡眠时长与 SCD-Q9 总分（EDF=3.575，P=0.004）和 OMTC 评分（EDF=4.478，P=0.010）之间的 U 型关联仍然存在。在年龄和性别调整后的 GAM（EDF=2.314，P<0.001）和进一步调整的 GAM（EDF=2.080，P=0.010）中，日常活动能力（DAA）评分与睡眠时长也呈非线性关联。
较长的睡眠时间（>8 小时）和较短的睡眠时间（<8 小时）都与更差的 SCCs 相关。未来的研究应该探讨管理睡眠时长对 SCD 及其向痴呆发展的保护作用。
