中老年人睡眠时间与全因死亡风险关系的队列研究

Relationship between Sleep Duration and All-cause Mortality in Middle-aged and Older Adults

背景中老年人睡眠时间与全因死亡关联的相关研究规模和随访时间差异较大,相关关系及推荐睡眠时间等研究结果仍存在争议。目的探讨中老年人睡眠时间与全因死亡风险之间的关联。方法2022年1—12月,根据编码手册,依据病例ID号合并中国健康与养老追踪调查(CHARLS)和中国老年健康影响因素跟踪调查(CLHLS)数据库的基线和随访信息,创建纵向研究队列,最终纳入43922名受访者。从CHARLS与CLHLS数据库中提取社会人口学特征、健康状况和健康相关行为、睡眠时间、死亡相关信息,并根据相关指标的测量和评价标准进行重新编码、变量转换等。采用Log-Rank检验的Kaplan-Meier法绘制生存曲线,采用Cox比例风险回归模型探讨中老年人群睡眠时间与死亡风险之间的关系,随后采用限制性立方样条(RCS)模型观察连续型变量睡眠时间对死亡风险的影响。结果43922名中老年人中,随访中位年限为6年,平均睡眠时间为7.32 h,其中每天睡眠时间≤5 h者9369名(21.33%),>5~6 h者7779名(17.71%),>6~7 h者295名(0.67%),>7~8 h者15611名(35.54%),>8~9 h者2567名(5.84%),>9~10 h者5011名(11.41%),>10 h者3290名(7.49%)。Kaplan-Meier生存分析结果显示,睡眠时间适中(>6~7 h)的中老年人生存概率最高,超长睡眠时间(>10 h)的中老年人生存概率最低。Cox比例风险回归模型结果显示,与睡眠时间为>10 h者的中老年人相比,睡眠时间≤5、>7~8、>8~9、>9~10 h可增加死亡风险〔HR(95%CI)分别为1.19(1.09,1.29)、1.16(1.08,1.25)、1.32(1.19,1.46)、1.12(1.04,1.22),P<0.05〕。RCS结果显示,睡眠时间与全因死亡风险之间存在“S”形非线性关联(P=0.023),每天睡眠时间为4.62~7.97 h对死亡风险无明显影响,<4.62 h与>7.97~10.00 h的睡眠时间均明显增加全因死亡风险。结论睡眠时间适中的中老年人生存概率最高,故中老年人的推荐睡眠时间为5~7 h。

Background The scale and follow-up time of studies related to the association between sleep duration and all-cause mortality in middle-aged and older adults vary widely,and the results of studies such as correlations and recommended sleep duration remain controversial.Objective To explore the association between sleep duration and the risk of all-cause mortality in middle-aged and older adults.Methods From January to December 2022,the longitudinal study cohort was created based on the case ID numbers of coding manual combined with baseline and follow-up data of the China Health and Retirement Longitudinal Study(CHARLS)and Chinese Longitudinal Healthy Longevity Study(CLHLS)databases from January to December in 2022,which ultimately included 43922 respondents.Social demographics,health status and health-related behaviors,sleep duration and death related information were extracted from CHARLS and CLHLS databases,recoding and variable transformations were performed according to the measurement and evaluation criteria of relevant indicators.The Kaplan-Meier method of Log-Rank test was used to plot survival curves,and the Cox proportional hazard regression model was used to explore the relationship between sleep duration and mortality risk in the middle-aged and older adults,followed by unrestricted cubic spline to observe the effect of the continuous-type variable of sleep duration on mortality risk.Results Among 43922 middle-aged and older adults with a median follow-up of 6 years and an average sleep duration of 7.32 h,9369 cases(21.33%)had sleep duration of≤5 h,7779 cases(17.71%)had sleep duration of>5-6 h,295 cases(0.67%)had sleep duration of>6-7 h,15611 cases(35.54%)had sleep duration of>7-8 h,2567 cases(5.84%)had sleep duration of>8-9 h,5011 cases(11.41%)had sleep duration of>9-10 h and 3290 cases had sleep duration>10 h(7.49%).Kaplan-Meier survival analysis showed that middle-aged and older adults with moderate sleep duration(>6-7 h)had the highest probability of survival,and those with extra-long sleep duration(>10 h)had the lowest probability of survival.Cox regression model results showed that compared with middle-aged and older adults with sleep duration>10 h,middle-aged and elderly adults with sleep duration of≤5 h〔HR(95%CI)=1.19(1.09,1.29),P<0.05〕,>7-8 h〔HR(95%CI)=1.16(1.08,1.25),P<0.05〕,>8-9 h〔HR(95%CI)=1.32(1.19,1.46),P<0.05〕,and>9-10 h〔HR(95%CI)=1.12(1.04,1.22),P<0.05〕had increased risk of death.Restricted cubic spline showed an S-shaped non-linear association between sleep duration and risk of all-cause death(P=0.023),with no significant association of sleep duration of 4.62-7.97 h with the risk of death,significant association of sleep duration<4.62 h and>7.97-10.00 h with all-cause mortality risk.Conclusion Middle-aged and older adults with moderate sleep duration had the highest probability of survival,so the recommended sleep duration for middle-aged and older adults is 5-7 h.