Leibniz Institute for Prevention Research and Epidemiology-BIPS, Bremen, Germany.
Department of Public Health and Primary Care, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium.
PLoS One. 2020 Jun 30;15(6):e0235049. doi: 10.1371/journal.pone.0235049. eCollection 2020.
Short sleep duration has been suggested to lead to insulin resistance both directly by altering glucose metabolism and indirectly through obesity. This study aims to investigate associations between nocturnal sleep duration and insulin resistance considering abdominal obesity as a mediator.
We analysed data of 3 900 children aged 2-15 years participating in the second (2009/10) and third (2013/14) examination wave of the European IDEFICS/I.Family study (hereafter referred to as baseline and follow-up). Information on nocturnal sleep duration was collected by questionnaires and age-standardised (SLEEP z-score). The homeostasis model assessment (HOMA) was calculated from fasting insulin and fasting glucose obtained from blood samples; waist circumference (WAIST) was measured with an inelastic tape. HOMA and WAIST were used as indicators for insulin resistance and abdominal obesity, respectively, and transformed to age- and sex-specific z-scores. Cross-sectional and longitudinal associations between SLEEP z-score and HOMA z-score were investigated based on a path model considering WAIST z-score as a mediator adjusting for relevant confounders.
Cross-sectionally, baseline SLEEP z-score was negatively associated with baseline WAIST z-score (unstandardised effect estimate -0.120, 95% confidence interval [-0.167; -0.073]). We observed no direct effect of baseline SLEEP z-score on baseline HOMA z-score but a negative indirect effect through baseline WAIST z-score (-0.042 [-0.058; -0.025]). Longitudinally, there was no direct effect of baseline SLEEP z-score on HOMA z-score at follow-up but a negative indirect effect through both baseline WAIST z-score and WAIST z-score at follow-up (-0.028 [-0.040; -0.016]).
Our results do not support the hypothesis of an association between short sleep duration and insulin resistance independent of abdominal obesity. However, longer sleep duration may exert short and long term beneficial effects on insulin resistance through its beneficial effects on abdominal obesity.
睡眠时长过短被认为会直接通过改变葡萄糖代谢，间接通过肥胖导致胰岛素抵抗。本研究旨在探讨夜间睡眠时间与胰岛素抵抗之间的关联，并考虑腹部肥胖作为中介。
我们分析了参与欧洲儿童肥胖症研究（IDEFICS）/家庭研究第二（2009/10 年）和第三（2013/14 年）波次的 3900 名 2-15 岁儿童的数据（以下简称基线和随访）。夜间睡眠时间信息通过问卷收集，并进行年龄标准化（SLEEP z 评分）。空腹胰岛素和空腹血糖来自血液样本，使用稳态模型评估（HOMA）计算；腰围（WAIST）使用无弹性带测量。HOMA 和 WAIST 分别作为胰岛素抵抗和腹部肥胖的指标，并转换为年龄和性别特异性 z 评分。基于路径模型，考虑 WAIST z 评分作为中介，调整相关混杂因素，横断面和纵向调查 SLEEP z 评分与 HOMA z 评分之间的关联。
横断面分析中，基线 SLEEP z 评分与基线 WAIST z 评分呈负相关（未标准化效应估计值 -0.120，95%置信区间 [-0.167；-0.073]）。我们没有观察到基线 SLEEP z 评分对基线 HOMA z 评分的直接影响，但通过基线 WAIST z 评分观察到负间接影响（-0.042 [-0.058；-0.025]）。纵向分析中，基线 SLEEP z 评分对随访时 HOMA z 评分无直接影响，但通过基线 WAIST z 评分和随访时 WAIST z 评分存在负间接影响（-0.028 [-0.040；-0.016]）。
我们的结果不支持短睡眠时间与胰岛素抵抗之间存在关联的假设，而不考虑腹部肥胖。然而，较长的睡眠时间可能通过对腹部肥胖的有益影响，对胰岛素抵抗产生短期和长期的有益影响。
