McGill University Faculty of Medicine, Montreal, Canada.
Research Institute, McGill University Health Centre, Montreal, Canada.
J Clin Sleep Med. 2022 Aug 1;18(8):1993-1999. doi: 10.5664/jcsm.10056.
Social jetlag (SJL) measures the discrepancy between circadian and social clocks. Using accelerometry-derived data, our objective was to assess the prevalence of SJL in young healthy children and determine the association of SJL and sleep with temperament.
Of 117 children participating in TARGet Kids!, a Canadian cohort of healthy preschool-aged children, 78 children (39 girls; 50%; mean age [SD]: 35.1 [20.5] months) were included. Sleep was measured objectively using accelerometry. Temperament dimensions (surgency, negative affectivity, and effortful control) were assessed with the very short forms of Rothbart's child and infant behavior questionnaires. We examined associations of SJL and sleep with temperament using multivariable linear regression models adjusted for sex, age, ethnicity, and preschool/daycare attendance.
20 out of 78 (25.6%) experienced SJL of greater than 30 minutes. SJL was greater in children who attended preschool/daycare compared with children who did not (26.3[18.8] minutes vs 17.6 [14.8] minutes; < .05). There was no evidence of an association between SJL and any temperament dimension. We found evidence of an association between increased sleep duration and increased negative affectivity scores (longer 24-hour sleep; β: 0.347; 95% confidence interval: 0.182, 0.512; < .0001; and longer nighttime sleep duration: β: 0.413; 95% confidence interval: 0.163, 0.663; = .002).
In our cohort, 1 in 4 preschool-aged children experienced SJL. Increased sleep duration was associated with increased negative affect, which could have implications for children developing internalizing behavior such as depression or low self-esteem. We found that sleep duration, but not SJL, was associated with temperament and may impact daytime behavior of young children.
Giannoumis M, Mok E, Borkhoff CM, et al. Association of accelerometry-derived social jetlag and sleep with temperament in children less than 6 years of age. . 2022;18(8):1993-1999.
社会时差（SJL）衡量的是生理时钟和社交时钟之间的差异。本研究使用加速计得出的数据，旨在评估年轻健康儿童中 SJL 的发生率，并确定 SJL 和睡眠与气质之间的关联。
在加拿大的 TARGet Kids！队列中，共有 117 名健康学龄前儿童参与了这项研究，其中 78 名儿童（39 名女孩；50%；平均年龄[标准差]：35.1[20.5]个月）被纳入研究。使用加速计客观地测量睡眠。使用 Rothbart 儿童和婴儿行为问卷的极短形式评估气质维度（冲动性、负性情绪和努力控制）。我们使用多变量线性回归模型，调整了性别、年龄、种族和学前/日托出勤率，以评估 SJL 和睡眠与气质之间的关联。
78 名儿童中有 20 名（25.6%）存在 30 分钟以上的 SJL。上学前/日托的儿童 SJL 比不上学前/日托的儿童更大（26.3[18.8]分钟比 17.6 [14.8]分钟；<0.05）。SJL 与任何气质维度之间均无关联。我们发现睡眠持续时间与负性情绪评分的增加之间存在关联（24 小时睡眠延长：β：0.347；95%置信区间：0.182，0.512；<0.0001；夜间睡眠延长：β：0.413；95%置信区间：0.163，0.663；=0.002）。
在我们的队列中，1/4 的学龄前儿童存在 SJL。睡眠持续时间的增加与负性情绪有关，这可能对儿童发展出内化行为（如抑郁或低自尊）产生影响。我们发现，是睡眠持续时间，而不是 SJL，与气质有关，可能会影响幼儿的日间行为。
Giannoumis M, Mok E, Borkhoff CM, et al. Association of accelerometry-derived social jetlag and sleep with temperament in children less than 6 years of age.. 2022;18(8):1993-1999.
