Objective: To investigate the association between sleep duration and blood pressure levels in school-aged children. Methods: A prospective cohort study was conclucted. The subjects were from the healthy children cohort in western China from 2021 to 2024. The baseline survey was conducted in 2021 in Shimian County, Sichuan Province, and Jiulongpo District Chongqing; in 2022 in Jiulongpo District, Chongqing; and in 2023 in Xishui County, Guizhou Province. Follow-up surveys were carried out in 2023 and 2024. A total of 15 662 participant-visits were finally included in the analysis. Among these, the baseline included 2 716 participants in 2021, 2 766 in 2022, and 1 977 in 2023. The first follow-up included 3 831 participants in 2023 and 2 058 in 2024, while the second follow-up comprised 2 314 participants in 2024. This study collected data on demographic characteristics, lifestyle factors, and sleep status. Additionally, this study conducted uniform measurements of height, weight, blood pressure, and brachial-ankle pulse wave velocity. The restricted cubic spline (RCS) regression model was utilized to examine the nonlinear relationship between average sleep duration, average sleep duration difference between weekends and weekdays, and the risk of elevated blood pressure to identify cutoff values. The association of different average sleep durations and differences in average sleep duration with elevated blood pressure were analyzed using multivariate mixed-effects logistic regression models. Based on the generalized linear mixed model, this study estimated the differences in blood pressure and brachial-ankle pulse wave velocity between various average sleep duration groups and among groups with different average sleep duration differences. Results: At baseline, there were 7 459 children with an average age of (10.8±2.3) years. Among them, 3 848 were boys, accounting for 51.6% of the total. The overall prevalence rate of elevated blood pressure was 13.4% (1 003/7 459). The age, height, body mass index (BMI), physical activity, and pulse wave velocity in the group with elevated blood pressure were all significantly higher than those in the normal blood pressure group (all P<0.05). The analysis results of the RCS the regression model indicated that the cut-off value for average sleep duration was 9 h/d. When the average sleep duration was less than 9 h/d, a negative correlation was observed between the average sleep duration and the risk of elevated blood pressure (P=0.008). The difference of average sleep duration was positively correlated with an increased risk of elevated blood pressure (P=0.005), with a cut-off value of 2.5 h/d for this difference. Using the average sleep duration of <9 h/d as a reference, the group with an average sleep duration of ≥9 h/d had a decreased risk of elevated blood pressure (OR=0.86, 95%CI: 0.75-0.99). Compared with the difference in average sleep duration of <2.5 h/d, the risk of elevated blood pressure was increased in the group with ≥2.5 h/d' difference in average sleep duration (OR=1.23, 95%CI: 1.06-1.43). The systolic blood pressure, diastolic blood pressure, and pulse wave velocity were significantly lower in the group with an average sleep duration of ≥9 h/d compared to the group with <9 h/d (all P<0.05). Conversely, these parameters were significantly higher in the group with a difference in average sleep duration of ≥2.5 h/d compared to the group with <2.5 h/d difference (all P<0.05). Conclusion: Inadequate average sleep duration (<9 h/d) and poor sleep regularity (average sleep duration difference between weekends and weekdays ≥2.5 h/d) are significant risk factors for elevated blood pressure in children.
目的： 探讨学龄儿童睡眠时长与血压水平的关联。 方法： 前瞻性队列研究。研究对象来自2021—2024年建立的西部地区健康儿童队列，其中分别于2021（四川省石棉县、重庆市九龙坡区）、2022（重庆市九龙坡区）、2023年（贵州省习水县）进行了基线调查，2023、2024年进行了随访。最终纳入15 662人次进行分析，其中基线：2021年2 716名，2022年2 766名，2023年1 977名；第1次随访：2023年3 831名，2024年2 058名；第2次随访：2024年2 314名。采集人口学特征、生活方式、睡眠状况等信息，统一测量身、高体重、血压和臂踝脉搏波传导速度。采用限制性立方样条（RCS）回归模型分析平均睡眠时长、休息日与工作日平均睡眠时长差异与血压偏高风险的非线性关系，确定切点值。基于多因素混合效应logistic回归模型分析不同平均睡眠时长、平均睡眠时长差异与血压偏高的关联。基于广义线性混合模型估计不同平均睡眠时长、睡眠时长差异组间血压及臂踝脉搏波传导速度的差异。 结果： 基线时7 459名儿童年龄（10.8±2.3）岁，男生3 848名（51.6%），总体血压偏高率为13.4%（1 003/7 459）。血压偏高组年龄、身高、体质指数、体力活动、臂踝脉搏波传导速度均高于血压正常组（均P<0.05）。RCS回归模型分析结果显示，平均睡眠时长切点值为9 h/d，当平均睡眠时长<9 h/d，平均睡眠时长与血压偏高风险呈负相关（P=0.008）；平均睡眠时长差异与血压偏高风险呈正相关（P=0.005），平均睡眠时长差异切点值是2.5 h/d。以平均睡眠时长<9 h/d组为参照，≥9 h/d组的血压偏高风险降低（OR=0.86，95%CI：0.75~0.99）。以平均睡眠时长差异<2.5 h/d组为参照，≥2.5 h/d组血压偏高风险增加（OR=1.23，95%CI：1.06~1.43）。平均睡眠时长≥9 h/d组收缩压、舒张压和臂踝脉搏波传导速度均低于<9 h/d组（均P<0.05）；平均睡眠时长差异≥2.5 h/d组收缩压、舒张压和臂踝脉搏波传导速度均高于<2.5 h/d组（均P<0.05）。 结论： 平均睡眠时长不足（<9 h/d）和睡眠规律性差（休息日与工作日平均睡眠时长差异≥2.5 h/d）是儿童血压偏高的危险因素。.