Chen Yan, Tan Jiping, Liu Yuewei, Dong Guang-Hui, Yang Bo-Yi, Li Nan, Wang Luning, Chen Gongbo, Li Shanshan, Guo Yuming
Department of Occupational and Environmental Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China.
Geriatric Neurology Department of the Second Medical Center & National Clinical Research Center for Geriatric Diseases, Chinese PLA General Hospital, Beijing, China.
Sci Total Environ. 2022 Nov 15;847:157441. doi: 10.1016/j.scitotenv.2022.157441. Epub 2022 Jul 19.
Evidence is limited for the association between outdoor light at night (LAN) and mild cognitive impairment (MCI), a transitional stage between normal aging and dementia and Alzheimer's disease in the elderly. In this study, the association between outdoor LAN and MCI was examined based on a multi-city study among veterans in China.
A total of 5496 participants from 18 cities across China were investigated during 2009-2011, selected using a multi-stage random sampling method. Participants' cognitive function was firstly assessed using the Mini Mental State Examination and the Montreal Cognitive Assessment in the Chinese version, and then was further confirmed by clinical examination. Participants' exposure to outdoor LAN was estimated using the Global Radiance Calibrated Nighttime Lights Product at a spatial resolution of around 1 km. The mixed-effects logistic regression model was used to examine the association between outdoor LAN and MCI.
After controlling for covariates, odds ratio (OR) and 95 % confidence intervals (95%CI) of MCI was 1.44 (95%CI: 1.36, 1.52) associated with per interquartile range (IQR = 21.17 nW/cm/sr) increase in exposure to outdoor LAN during the 3 years before the investigation, and for categorical variable of LAN, the highest OR was observed for the highest against the lowest quartile of LAN with a monotonically increasing trend (p values for trend <0.001). Furthermore, higher ORs were observed for females, veterans who had less educational attainment, and had no regular social activities.
Our study revealed that exposure to excessive outdoor LAN was associated with higher risk of MCI. Effective measures should be taken to reduce LAN exposure, which may help to prevent MCI.
夜间室外光（LAN）与轻度认知障碍（MCI）之间关联的证据有限，MCI是老年人正常衰老与痴呆症及阿尔茨海默病之间的过渡阶段。在本研究中，基于中国退伍军人的多城市研究，对室外LAN与MCI之间的关联进行了考察。
2009年至2011年期间，对来自中国18个城市的5496名参与者进行了调查，采用多阶段随机抽样方法进行选取。首先使用中文版简易精神状态检查表和蒙特利尔认知评估量表对参与者的认知功能进行评估，然后通过临床检查进一步确认。使用空间分辨率约为1 km的全球辐射校准夜间灯光产品估算参与者对室外LAN的暴露情况。采用混合效应逻辑回归模型考察室外LAN与MCI之间的关联。
在控制协变量后，调查前3年室外LAN暴露每增加一个四分位数间距（IQR = 21.17 nW/cm/sr），MCI的比值比（OR）及95%置信区间（95%CI）为1.44（95%CI：1.36，1.52），对于LAN的分类变量，观察到LAN最高四分位数与最低四分位数相比OR最高，且呈单调递增趋势（趋势p值<0.001）。此外，女性、教育程度较低且无规律社交活动的退伍军人的OR更高。
我们的研究表明，暴露于过多的室外LAN与MCI风险较高有关。应采取有效措施减少LAN暴露，这可能有助于预防MCI。
