Clinical Research Center, the Third Xiangya Hospital, Central South University, Changsha, 410013, China.
National Center for Chronic and Noncommunicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Xicheng District, Beijing, 100050, China.
BMC Med. 2023 Mar 16;21(1):95. doi: 10.1186/s12916-023-02822-w.
While epidemiological studies have found correlations between light at night (LAN) and health effects, none has so far investigated the impacts of LAN on population mortality yet. We aimed to estimate the relative risk for mortality from exposure to LAN in Mainland China.
This time-stratified case-crossover nationwide study used NPP-VIIRS to obtain daily LAN data of Mainland China between 2015 and 2019. The daily mortality data were obtained from the Disease Surveillance Point System in China. Conditional Poisson regression models were applied to examine the relative risk (RR) for mortality along daily LAN in each county, then meta-analysis was performed to combine the county-specific estimates at the national or regional level.
A total of 579 counties with an average daily LAN of 4.39 (range: 1.02-35.46) were included in the main analysis. The overall RRs per 100 nW/cm/sr increases in daily LAN were 1.08 (95%CI: 1.05-1.11) for all-cause mortality and 1.08 (95%CI: 1.05-1.11) for natural-cause mortality. A positive association between LAN and all natural cause-specific mortality was observed, of which the strongest effect was observed on mortality caused by neuron system disease (RR = 1.32, 95%CI: 1.14-1.52). The results were robust in both younger and old, as well as in males and females. The more pronounced effect of LAN was observed in median LAN-level regions. Combined with an exposure-response curve, our study suggests a non-linear association between LAN and mortality in China.
Our study shows LAN is associated with mortality in China, particularly for neuron system disease-related mortality. These findings have important implications for public health policy establishment to minimize the health consequences of light pollution.
虽然流行病学研究已经发现夜间光（LAN）与健康影响之间存在相关性，但迄今为止还没有研究 LAN 对人口死亡率的影响。我们旨在估计接触 LAN 对中国大陆人群死亡率的相对风险。
本时间分层病例交叉全国性研究使用 NPP-VIIRS 获取 2015 年至 2019 年中国大陆每日 LAN 数据。每日死亡率数据来自中国疾病监测点系统。应用条件泊松回归模型检验每个县的每日 LAN 死亡率的相对风险（RR），然后进行荟萃分析以合并全国或地区水平的县级特定估计值。
共有 579 个县纳入了主要分析，平均每日 LAN 为 4.39（范围：1.02-35.46）。每日 LAN 每增加 100 nW/cm/sr，总死亡率的总体 RR 为 1.08（95%CI：1.05-1.11），自然原因死亡率的 RR 为 1.08（95%CI：1.05-1.11）。LAN 与所有自然原因特异性死亡率之间存在正相关关系，其中神经系统疾病死亡率的影响最强（RR=1.32，95%CI：1.14-1.52）。在年轻和年老、男性和女性中，结果均稳健。在 LAN 中位数水平较高的地区，LAN 的影响更为明显。结合暴露-反应曲线，我们的研究表明，LAN 与中国的死亡率之间存在非线性关系。
我们的研究表明，LAN 与中国的死亡率有关，特别是与神经系统疾病相关的死亡率。这些发现对制定公共卫生政策以最大程度减少光污染对健康的影响具有重要意义。
