背景:随着气候变化,由于降雪减少和云量增加,预计全球北部地区冬季的日光减少。虽然冬季与心理健康问题有关,冬季日光的作用几乎没有被研究过。我们研究了冬季客观暴露于全球辐射和自我报告的日光暴露与抑郁和睡眠问题症状的纵向关联。
方法:我们的分析样本包括来自三项瑞典纵向职业健康调查(2012年,2014年和2016年)的15,619名受访者。客观暴露是全球辐射(MJ/m2,11月至1月和11月至2月)。主观暴露是基于自己报告的白天在户外度过的时间(<1h与≥1h,11月至1月)。使用(霍普金斯)症状清单的六项子量表评估抑郁症的症状。通过设计控制时间不变参与者特征的条件逻辑回归的固定效应方法和时变协变量被添加到模型中。
结果:4个月平均全球辐射增加1个单位与抑郁症状的几率较低相关(OR0.69,95%CI0.52-0.91)。这些发现通过四个月的累积暴露得到证实(OR0.91,95%CI0.85-0.98)。与暴露时间<1小时相比,报告冬季暴露时间≥1小时的个体不太可能报告抑郁症状(OR0.72,95%CI0.60-0.82)。更高的三个月全球辐射暴露表明睡眠问题的保护性关联。
结论:这些研究结果表明,冬季暴露在日光下的比例较高可能会降低抑郁症状的可能性。
BACKGROUND: With climate change Northern areas of the globe are expected to have less
daylight during winters due to less snow and more cloudiness. While wintertime has been linked to mental health problems, the role of wintertime
daylight has been scarcely studied. We examined longitudinal associations for wintertime objective exposure to global radiation and self-reported
daylight exposure with symptoms of depression and sleep problems.
METHODS: Our analytical sample included 15,619 respondents from three Swedish Longitudinal Occupational Surveys of Health (2012, 2014 and 2016). Objective exposure was global radiation (MJ/m2, November-January and November-February). Subjective exposure was based on self-reported time spent outdoors in
daylight (<1 h vs. ≥ 1 h, November-January). Symptoms of depression were evaluated using a six-item subscale of the (Hopkins) Symptom Checklist. Fixed-effects method with conditional logistic regression controlled for time-invariant participant characteristics by design and time-varying covariates were added into models.
RESULTS: One unit increase in the four-month averaged global radiation was associated with lower odds of depressive symptoms (OR 0.69, 95 % CI 0.52-0.91). These findings were confirmed using four-month cumulative exposure (OR 0.91, 95 % CI 0.85-0.98). Individuals reporting ≥ 1 h exposure to
daylight during winter months were less likely to report depressive symptoms (OR 0.72, 95 % CI 0.60-0.82) compared to time when their exposure was < 1 h. Higher three-month exposure to global radiation suggested a protective association for sleep problems.
CONCLUSIONS: These findings suggest that higher exposure to daylight during winters may contribute to lower likelihood of depression symptoms.