Effects of high temperature and high humidity exposure on hospitalization for circulatory system diseases and respiratory system diseases
10.19485/j.cnki.issn2096-5087.2026.09.004
- Author:
GU Shaohua
;
LU Beibei
;
LU Wenhan
;
Qiu Yidan
;
Wang Yaqi
- Publication Type:Journal Article
- Keywords:
high temperature;
high humidity;
circulatory system diseases;
respiratory system diseases;
hospitalization;
case-crossover design
- From:
Journal of Preventive Medicine
2026;38(9):880-885
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To assess the effects of combined high temperature and high humidity exposure on the risk of hospitalization for circulatory system diseases and respiratory system diseases.
Methods:Data on inpatients with circulatory system diseases and respiratory system diseases from 3 hospitals in the main urban area of Ningbo City, Zhejiang Province were collected for the periods of May to October in each year from 2022 to 2025, and the meteorological data of the same period were obtained from Ningbo Meteorological Service Center. A time-stratified case-crossover design was used to separately construct association models of daily mean temperature and wet-bulb globe temperature (WBGT) with the hospitalization counts of circulatory system diseases and respiratory system diseases. The optimal high temperature exposure assessment indicator was selected by comparing the model goodness-of-fit and the effect size of extreme high temperature (≥99th percentile). Exposure-response relationships between extreme high temperature and the risk of hospitalization for circulatory system diseases and respiratory system diseases were constructed using a temperature-humidity stratified interaction model, stratified by low and high relative humidity based on the 50th percentile.
Results:From May to October each year during 2022-2025, a total of 27 845 hospitalizations for circulatory system diseases and 27 023 hospitalizations for respiratory system diseases were recorded in Ningbo City. The median daily mean temperature and WBGT were 26.55 (interquartile range, 7.70) ℃ and 25.11 (interquartile range, 7.11) ℃, respectively. When WBGT was used as the exposure indicator, extreme high temperature exposure was positively associated with the hospitalization risks of circulatory system diseases (RR=1.192, 95%CI: 1.014-1.401) and respiratory system diseases (RR=1.278, 95%CI: 1.094-1.494). When daily mean temperature was used as the exposure indicator, extreme high temperature exposure was positively associated with the hospitalization risk of respiratory system diseases (RR=1.260, 95%CI: 1.080-1.471), while the association with the hospitalization risk of circulatory system diseases was not statistically significant (RR=1.146, 95%CI: 0.974-1.349). Considering that the quasi-Akaike information criterion value of this model was larger than that of the WBGT-based model, WBGT was selected as the optimal high temperature exposure assessment indicator. The temperature-humidity stratified interaction analysis showed that under high-humidity conditions, extreme high-temperature exposure was associated with higher risks of hospitalization for circulatory system diseases (RR=1.480, 95%CI: 1.000-2.192) and respiratory system diseases (RR=1.617, 95%CI: 1.102-2.374) in the overall population. Subgroup analysis showed that under high-humidity conditions, extreme high-temperature exposure was associated with higher risks of hospitalization for circulatory system diseases (RR=1.901, 95%CI: 1.187-3.044) and respiratory system diseases (RR=1.848, 95%CI: 1.074-3.179) among males, and with higher risk of hospitalization for respiratory system diseases among those aged 45-<65 years (RR=2.691, 95%CI: 1.127-6.426).
Conclusion:Combined exposure to high temperature and high humidity can increases the hospitalization risks of circulatory system diseases and respiratory system diseases, and males and the middle-aged population are susceptible high-risk populations.
- Full text:2026111215064973035高温高湿暴露对循环系统和呼吸系统疾病住院的影响.pdf