Department of Family Medicine & Public Health, University of California, San Diego, La Jolla, CA.
Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN.
Sleep. 2020 Jan 13;43(1). doi: 10.1093/sleep/zsz205.
Activities throughout the day, including sleep, sedentary behavior (SB), light-intensity physical activity (LIPA), and moderate to vigorous physical activity (MVPA) are independently associated with cardiometabolic health. Few studies have examined interrelationships between sleep and 24-hour activity and associations with cardiometabolic risk. The objective of this study is to understand how replacing time in SB, LIPA, or MVPA with sleep impacts cardiometabolic risk.
Women's Health Initiative OPACH Study participants (N = 3329; mean age = 78.5 ± 6) wore ActiGraph GT3X+ accelerometers 24 hours/7 days. Adjusted linear regression estimated the relationship between sleep duration and cardiometabolic markers. Separately for shorter (<8 hours) and longer (≥8 hours) sleepers, isotemporal substitution models estimated the cross-sectional associations with cardiometabolic markers with reallocating time in daytime activities to or from sleep.
Longer sleep duration was associated with higher insulin, HOMA-IR, glucose, total cholesterol, and triglycerides (all p < 0.05). The associations between sleep duration and C-reactive protein, waist circumference, and body mass index (BMI) were U-shaped (both p < 0.05). For shorter sleepers, reallocating 33 minutes of MVPA to sleep was associated with higher values of insulin, HOMA-IR, glucose, triglycerides, waist circumference, and BMI (0.7%-11.5%). Replacing 91 minutes of SB time with sleep was associated with lower waist circumference and BMI (-1.3%, -1.8%). For long sleepers, shifting 91 minutes of sleep to SB was associated with higher waist circumference and BMI (1.3%, 1.4%).
This is one of the first isotemporal analyses to include objectively measured sleep duration. Results illuminate possible cardiometabolic risks and benefits of reallocating time to or from sleep.
白天的活动，包括睡眠、久坐行为（SB）、低强度体力活动（LIPA）和中高强度体力活动（MVPA），均与心血管代谢健康独立相关。很少有研究探讨睡眠与 24 小时活动之间的相互关系及其与心血管代谢风险的关联。本研究的目的是了解用睡眠替代 SB、LIPA 或 MVPA 的时间如何影响心血管代谢风险。
妇女健康倡议 OPACH 研究参与者（N=3329；平均年龄=78.5±6 岁）佩戴 ActiGraph GT3X+加速度计 24 小时/7 天。调整线性回归估计了睡眠持续时间与心血管代谢标志物之间的关系。对于睡眠较短（<8 小时）和较长（≥8 小时）的睡眠者，分别使用等时替代模型，用日间活动的时间来分配或重新分配睡眠，评估与心血管代谢标志物的横断面关联。
更长的睡眠时间与更高的胰岛素、HOMA-IR、葡萄糖、总胆固醇和甘油三酯（均 P<0.05）相关。睡眠持续时间与 C 反应蛋白、腰围和体重指数（BMI）之间呈 U 型关系（均 P<0.05）。对于睡眠较短的人，将 33 分钟的 MVPA 重新分配到睡眠中与更高的胰岛素、HOMA-IR、葡萄糖、甘油三酯、腰围和 BMI 值相关（0.7%-11.5%）。用 91 分钟的 SB 时间替代睡眠与腰围和 BMI 降低相关（-1.3%，-1.8%）。对于睡眠较长的人，将 91 分钟的睡眠转移到 SB 中与更高的腰围和 BMI 相关（1.3%，1.4%）。
这是最早将客观测量的睡眠时间纳入的等时分析之一。结果阐明了重新分配睡眠时间可能带来的心血管代谢风险和益处。
