Abstract：
To investigate the association of baseline nocturnal sleep duration and sleep changes with functional disability in middle-aged and elderly Chinese.
Data for this study were collected from the China Health and Retirement Longitudinal Study (CHARLS) from baseline (2011) to the Wave 3 follow-up (2018). 8361 participants free of IADL disability in 2011 and aged ≥ 45 years old were recruited and prospectively followed till 2018 to analyze the association between baseline nocturnal sleep duration and IADL disability. Of these 8361 participants, a total of 6948 participants had no IADL disability at the first three follow-up visits and completed the 2018 follow-up to analyze the association between nocturnal sleep changes and IADL disability. Nocturnal sleep duration (hours) was self-reported at baseline. The coefficient of variation (CV) of nocturnal sleep duration at baseline and three follow-up visits was used to calculate sleep changes and classified into mild, moderate, and severe degrees by the quantiles. Cox proportional hazards regression model was used to analyze the association of baseline nocturnal sleep duration with IADL disability, and the binary logistic regression model was used to analyze the association of nocturnal sleep changes with IADL disability.
Among the 8361 participants of 50237.5 person-years follow-up with a median follow-up of 7 years, 2158 (25.81%) participants developed IADL disabilities. Higher risks of IADL disability were observed among participants with sleep duration <7 h [HR(95%): 1.23(1.09-1.38)], 8∼<9 h [HR(95%): 1.05(1.00-1.32)] and ≥9 h [HR(95%): 1.21(1.01-1.45)] compared to those with 7∼<8 h. Among the 6948 participants, a total of 745 (10.72%) participants finally developed IADL disabilities. Compared with mild nocturnal sleep changes, moderate [OR(95%): 1.48(1.19-1.84)] and severe [OR(95%): 2.43(1.98-3.00)] sleep changes increased the probability of IADL disability. The restricted cubic spline model showed that a higher degree of nocturnal sleep changes was associated with a greater probability of IADL disability.
Both insufficient and excessive nocturnal sleep duration were associated with higher risk of IADL disability in middle-aged and elderly adults, independent of the participants\' gender, age, and napping habits. Higher nocturnal sleep changes were associated with a higher probability of disability in IADL. These findings highlight the importance of appropriate and stable nocturnal sleep, and the need to pay attention to population differences in the impact of nocturnal sleep duration on health.
Data for this study were collected from the China Health and Retirement Longitudinal Study (CHARLS) from baseline (2011) to the Wave 3 follow-up (2018). 8361 participants free of IADL disability in 2011 and aged ≥ 45 years old were recruited and prospectively followed till 2018 to analyze the association between baseline nocturnal sleep duration and IADL disability. Of these 8361 participants, a total of 6948 participants had no IADL disability at the first three follow-up visits and completed the 2018 follow-up to analyze the association between nocturnal sleep changes and IADL disability. Nocturnal sleep duration (hours) was self-reported at baseline. The coefficient of variation (CV) of nocturnal sleep duration at baseline and three follow-up visits was used to calculate sleep changes and classified into mild, moderate, and severe degrees by the quantiles. Cox proportional hazards regression model was used to analyze the association of baseline nocturnal sleep duration with IADL disability, and the binary logistic regression model was used to analyze the association of nocturnal sleep changes with IADL disability.
Among the 8361 participants of 50237.5 person-years follow-up with a median follow-up of 7 years, 2158 (25.81%) participants developed IADL disabilities. Higher risks of IADL disability were observed among participants with sleep duration <7 h [HR(95%): 1.23(1.09-1.38)], 8∼<9 h [HR(95%): 1.05(1.00-1.32)] and ≥9 h [HR(95%): 1.21(1.01-1.45)] compared to those with 7∼<8 h. Among the 6948 participants, a total of 745 (10.72%) participants finally developed IADL disabilities. Compared with mild nocturnal sleep changes, moderate [OR(95%): 1.48(1.19-1.84)] and severe [OR(95%): 2.43(1.98-3.00)] sleep changes increased the probability of IADL disability. The restricted cubic spline model showed that a higher degree of nocturnal sleep changes was associated with a greater probability of IADL disability.
Both insufficient and excessive nocturnal sleep duration were associated with higher risk of IADL disability in middle-aged and elderly adults, independent of the participants\' gender, age, and napping habits. Higher nocturnal sleep changes were associated with a higher probability of disability in IADL. These findings highlight the importance of appropriate and stable nocturnal sleep, and the need to pay attention to population differences in the impact of nocturnal sleep duration on health.
摘要：
目的：探讨中老年人夜间睡眠时间和睡眠变化与功能性残疾的关系。
方法：本研究的数据来自中国健康与退休纵向研究（CHARLS），从基线（2011年）到第3波随访（2018年）。招募8361名2011年无IADL残疾且年龄≥45岁的参与者，并前瞻性随访至2018年，以分析基线夜间睡眠时间与IADL残疾之间的关联。在8361名参与者中，共有6948名参与者在前3次随访中没有出现IADL残疾,并完成了2018年的随访,以分析夜间睡眠变化与IADL残疾之间的关联.夜间睡眠持续时间(小时)在基线时自我报告。使用基线和三次随访时夜间睡眠持续时间的变异系数（CV）来计算睡眠变化，并将其分为轻度，中度,分位数的严重程度。Cox比例风险回归模型用于分析基线夜间睡眠时间与IADL残疾的相关性。采用二元logistic回归模型分析夜间睡眠变化与IADL残疾的相关性。
结果：在50237.5人年随访的8361名参与者中，中位随访时间为7年，2158名(25.81%)参与者出现IADL残疾。在睡眠时间<7小时的参与者中观察到IADL残疾的风险更高[HR（95％）：1.23（1.09-1.38）]，8h<9h[HR(95%):1.05(1.00-1.32)]和≥9h[HR(95%):1.21(1.01-1.45)]与7h<8h相比。在6948名参与者中，共有745名(10.72%)参与者最终发展为IADL残疾.与轻度夜间睡眠变化相比，中度[OR（95％）：1.48（1.19-1.84）]和重度[OR（95％）：2.43（1.98-3.00）]睡眠变化增加了IADL残疾的可能性。受限三次样条模型表明，夜间睡眠变化程度越高，IADL残疾的可能性越大。
结论：在中老年人中，夜间睡眠时间不足和过多与IADL残疾的风险较高有关，独立于参与者的性别，年龄,和小睡的习惯。在IADL中，较高的夜间睡眠变化与较高的残疾概率相关。这些发现强调了适当和稳定的夜间睡眠的重要性。并且需要注意人群夜间睡眠时间的差异对健康的影响。
方法：本研究的数据来自中国健康与退休纵向研究（CHARLS），从基线（2011年）到第3波随访（2018年）。招募8361名2011年无IADL残疾且年龄≥45岁的参与者，并前瞻性随访至2018年，以分析基线夜间睡眠时间与IADL残疾之间的关联。在8361名参与者中，共有6948名参与者在前3次随访中没有出现IADL残疾,并完成了2018年的随访,以分析夜间睡眠变化与IADL残疾之间的关联.夜间睡眠持续时间(小时)在基线时自我报告。使用基线和三次随访时夜间睡眠持续时间的变异系数（CV）来计算睡眠变化，并将其分为轻度，中度,分位数的严重程度。Cox比例风险回归模型用于分析基线夜间睡眠时间与IADL残疾的相关性。采用二元logistic回归模型分析夜间睡眠变化与IADL残疾的相关性。
结果：在50237.5人年随访的8361名参与者中，中位随访时间为7年，2158名(25.81%)参与者出现IADL残疾。在睡眠时间<7小时的参与者中观察到IADL残疾的风险更高[HR（95％）：1.23（1.09-1.38）]，8h<9h[HR(95%):1.05(1.00-1.32)]和≥9h[HR(95%):1.21(1.01-1.45)]与7h<8h相比。在6948名参与者中，共有745名(10.72%)参与者最终发展为IADL残疾.与轻度夜间睡眠变化相比，中度[OR（95％）：1.48（1.19-1.84）]和重度[OR（95％）：2.43（1.98-3.00）]睡眠变化增加了IADL残疾的可能性。受限三次样条模型表明，夜间睡眠变化程度越高，IADL残疾的可能性越大。
结论：在中老年人中，夜间睡眠时间不足和过多与IADL残疾的风险较高有关，独立于参与者的性别，年龄,和小睡的习惯。在IADL中，较高的夜间睡眠变化与较高的残疾概率相关。这些发现强调了适当和稳定的夜间睡眠的重要性。并且需要注意人群夜间睡眠时间的差异对健康的影响。
