Chamorro R, Algarín C, Garrido M, Causa L, Held C, Lozoff B, Peirano P
Sleep Laboratory, Institute of Nutrition and Food Technology (INTA), University of Chile, Santiago, Chile.
Electrical Engineering Department, University of Chile, Santiago, Chile.
Int J Obes (Lond). 2014 Aug;38(8):1120-5. doi: 10.1038/ijo.2013.238. Epub 2013 Dec 19.
Epidemiological evidence shows an inverse relationship between sleep duration and overweight/obesity risk. However, there are few polysomnographic studies that relate the organization of sleep stages to pediatric overweight (OW). We compared sleep organization in otherwise healthy OW and normal-weight (NW) 10-year-old children.
Polysomnographic assessments were performed in 37 NW and 59 OW children drawn from a longitudinal study beginning in infancy. Weight and height were used to evaluate body mass index (BMI) according to international criteria. Non-rapid eye movement (NREM) sleep (stages N1, N2 and N3), rapid eye movement (REM) sleep (stage R) and wakefulness (stage W) were visually scored. Sleep parameters were compared in NW and OW groups for the whole sleep period time (SPT) and for each successive third of it using independent Student's t-tests or nonparametric tests. The relationship between BMI and sleep variables was evaluated by correlation analyses controlling for relevant covariates.
The groups were similar in timing of sleep onset and offset, and sleep period time. BMI was inversely related to total sleep time (TST) and sleep efficiency. OW children showed reduced TST, sleep efficiency and stage R amount, but higher stage W amount. In analysis by thirds of the SPT, the duration of stage N3 episodes was shorter in the first third and longer in the second third in OW children as compared with NW children.
Our results show reduced sleep amount and quality in otherwise healthy OW children. The lower stage R amount and changes involving stage N3 throughout the night suggest that OW in childhood is associated with modifications not only in sleep duration, but also in the ongoing night time patterns of NREM sleep and REM sleep stages.
流行病学证据显示睡眠时间与超重/肥胖风险之间存在负相关关系。然而，很少有多导睡眠图研究将睡眠阶段的组织与儿童超重（OW）联系起来。我们比较了健康的OW和正常体重（NW）的10岁儿童的睡眠结构。
对37名NW儿童和59名OW儿童进行了多导睡眠图评估，这些儿童来自一项始于婴儿期的纵向研究。根据国际标准，使用体重和身高来评估体重指数（BMI）。对非快速眼动（NREM）睡眠（N1、N2和N3阶段）、快速眼动（REM）睡眠（R阶段）和清醒（W阶段）进行视觉评分。使用独立样本t检验或非参数检验比较NW组和OW组在整个睡眠时间（SPT）及其连续的三分之一时间段内的睡眠参数。通过控制相关协变量的相关分析评估BMI与睡眠变量之间的关系。
两组在入睡和起床时间以及睡眠时间方面相似。BMI与总睡眠时间（TST）和睡眠效率呈负相关。OW儿童的TST、睡眠效率和R阶段时间减少，但W阶段时间增加。在按SPT的三分之一进行分析时，与NW儿童相比，OW儿童在第一个三分之一时间段内N3阶段的持续时间较短，在第二个三分之一时间段内较长。
我们的结果表明，在其他方面健康的OW儿童中，睡眠量和质量有所下降。较低的R阶段时间以及夜间N3阶段的变化表明，儿童期OW不仅与睡眠时间的改变有关，还与NREM睡眠和REM睡眠阶段的夜间持续模式的改变有关。
