冬季室内热环境与糖尿病关联性初探

Preliminary study of the relationship between the indoor thermal environment in the winter and diabetes

中国糖尿病患病人数逐年上升,糖尿病及其并发症会造成巨大的个人及社会负担。近年研究表明,适度的寒冷暴露可能会改善机体的胰岛素敏感性,并防止肥胖相关的胰岛素抵抗和高血糖症的发展。该文旨在通过横断面研究方法,初步探究冬季室内热环境与居民糖尿病患病风险之间的潜在关联。根据不同采暖方式,将冬季室内热环境划分为不同水平,其中居民糖尿病患病数据分别来源于中国糖尿病患病率横断面研究数据、历年统计年鉴数据及中国健康与养老追踪调查(China Health and Retirement Longitudinal Study,CHARLS)数据库。在省级尺度纳入17个省(自治区、直辖市)的研究结果,结果表明冬季室内热环境与糖尿病患病显著相关(相关系数为0.505,P=0.039)。在个体尺度共纳入研究对象8403人,分析结果表明,冬季室内热环境、性别、年龄和身体质量指数(body mass index, BMI)与糖尿病相关(P<0.050)。本研究从较长的时间尺度上为冷暴露与糖尿病的实验室研究提供了实际环境中的支持与佐证,并对夏热冬冷地区建筑室内热环境营造提供一定借鉴和参考。

[Objective] In the past decades, the lifestyle of the Chinese population has changed because of rapid economic development. The incidence and prevalence of diabetes are increasing in China. Diabetes and its complications can cause substantial personal and social burdens. Recent experimental studies have shown that cold exposure may enhance insulin sensitivity and prevent the development of obesity-related insulin resistance and hyperglycemia. However, there is insufficient evidence of the correlation between cold exposure and diabetes in the real environment of daily life. In contrast, although people spend most of their life indoors, existing evidence usually focuses on the relationship between the outdoor thermal environment and diabetes without considering the effect of the indoor thermal environment. This study preliminarily examines the association between the real indoor thermal environment during the winter and the risk of diabetes. [Methods] The study was analyzed from provincial and individual perspectives. At the provincial level, the analysis included 17 provinces. The diabetes prevalence data were obtained from the cross-sectional study on diabetes prevalence in China through Thyroid Disorders, Iodine Status, and Diabetes Epidemiological Survey(TIDE). The level of cold exposure was calculated based on the prevalence of central heating, according to the statistical yearbook data of the country and each region. Spearman correlation analyses were conducted to reveal the correlation between cold exposure and diabetes. The data were obtained from the China Health and Retirement Longitudinal Study(CHARLS) database at the individual level. Subjects' age, gender, body mass index(BMI), smoking, drinking, socioeconomic status, and whether they experienced indoor cold exposure in the winter were considered. Subjects were divided into two categories based on whether they experienced indoor cold exposure in the winter from 2011 to 2015. Chi-square and logistic regression analyses were applied to explore the correlation between indoor cold exposure and diabetes at the individual level. [Results] At the provincial level, the results indicated a significant negative correlation between indoor cold exposure in the winter and diabetes prevalence(Spearman's correlation coefficient=0.505, P=0.039). At the individual level, 1) 8 403 subjects were eligible for analysis, and 1 138(13.5%) had diabetes. 2) A total of 7 879 subjects had experienced indoor cold exposure in the winter. A significant difference was discovered in the prevalence rate between the group with and without cold exposure(P<0.001). 3) After age, gender, BMI, and smoking factors were adjusted, the group with indoor cold exposure in the winter was significantly associated with a 23% reduction in the risk of diabetes compared with the group without indoor cold exposure(OR=0.77, 95% CI: 0.61~0.97). [Conclusions] At the provincial and individual levels, indoor cold exposure in the winter is significantly associated with diabetes. This study provides evidence for the correlation between the indoor thermal environment and diabetes prevalence on a long-time scale. This supports the conclusions of laboratory studies on cold exposure and diabetes and guides indoor thermal environment design.