Objective:To explore the associations of temperature, relative humidity, and their interaction effect with fall risk.Methods:Data on fall cases were collected using the national injury surveillance system from May to September, in 2006-2022 in Hubei Province. Combined with the meteorological and air pollution data, we conducted a time-stratified case-crossover design and used conditional logistic regression models and distributed lag nonlinear models to examine the exposure-response relationships between temperature, humidity, and fall risk. We further divided the low and the high temperature groups and the low and the high relative humidity groups and analyzed the excess risk ( ER) of falls attributed to dry-hot or wet-hot events. Finally, we calculated the additive interactions of temperature and humidity on fall risk. Results:A total of 55 401 fall cases were included. With the increase in temperature and relative humidity decrease, the exposure-response curves of fall showed nonlinear upward trends among all populations. Gender and age differences were found in temperature-fall and relative humidity-fall risk relationships. Compared with wet-non-hot (normal temperature and high relative humidity) events, the ER of fall in dry-hot (high temperature and low relative humidity) events was 14.80% (95% CI: 9.69%- 20.15%), and the ER of wet-hot (high temperature and high relative humidity) events was 9.59% (95% CI: 2.52%-17.13%). However, there was no statistically significant difference between dry-hot and wet-hot events in the fall, and no statistically significant difference between different genders, ages, occupations, and fall occurred place (all P>0.05). No significant synergistic additive interaction was found between temperature and relative humidity on fall risk (relative excess risk due to interaction=-0.08, 95% CI: -0.19-0.02). Conclusions:Higher temperatures and lower relative humidity were associated with increased fall risk. Both dry-hot and wet-hot events had a higher risk of fall, while high temperature and low humidity have no synergistic effect on fall risk.

Objective:To explore the associations of temperature, relative humidity, and their interaction effect with fall risk.Methods:Data on fall cases were collected using the national injury surveillance system from May to September, in 2006-2022 in Hubei Province. Combined with the meteorological and air pollution data, we conducted a time-stratified case-crossover design and used conditional logistic regression models and distributed lag nonlinear models to examine the exposure-response relationships between temperature, humidity, and fall risk. We further divided the low and the high temperature groups and the low and the high relative humidity groups and analyzed the excess risk ( ER) of falls attributed to dry-hot or wet-hot events. Finally, we calculated the additive interactions of temperature and humidity on fall risk. Results:A total of 55 401 fall cases were included. With the increase in temperature and relative humidity decrease, the exposure-response curves of fall showed nonlinear upward trends among all populations. Gender and age differences were found in temperature-fall and relative humidity-fall risk relationships. Compared with wet-non-hot (normal temperature and high relative humidity) events, the ER of fall in dry-hot (high temperature and low relative humidity) events was 14.80% (95% CI: 9.69%- 20.15%), and the ER of wet-hot (high temperature and high relative humidity) events was 9.59% (95% CI: 2.52%-17.13%). However, there was no statistically significant difference between dry-hot and wet-hot events in the fall, and no statistically significant difference between different genders, ages, occupations, and fall occurred place (all P>0.05). No significant synergistic additive interaction was found between temperature and relative humidity on fall risk (relative excess risk due to interaction=-0.08, 95% CI: -0.19-0.02). Conclusions:Higher temperatures and lower relative humidity were associated with increased fall risk. Both dry-hot and wet-hot events had a higher risk of fall, while high temperature and low humidity have no synergistic effect on fall risk.

Objective:To explore sex and rural-urban differences in the associations of different blood pressure levels with the risk of prediabetes.Methods:We used a multi-stage stratified cluster random sampling method to investigate 21 637 residents aged ≥18 years from 10 survey areas in Hubei province in 2020. The data on questionnaire, physical measurements, and laboratory indicators of the participants were collected. The associations of different blood pressure levels with risk of prediabetes by sex and regions were analyzed using multivariate logistic regressions after complex weighting.Results:A total of 16 111 subjects were included. The prevalence (95% CI) of prediabetes, impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and IFG complicated with IGT were 25.1% (14.4%-35.9%), 12.7% (3.2%-22.1%), 8.1% (6.3%-9.8%), and 4.4% (2.3%-6.5%), respectively. After multivariate adjustment, the risk of prediabetes, IFG, IGT, and IFG complicated with IGT increased with the increment of blood pressure (both P for trend <0.05). The positive dose-response relationships between blood pressure levels and risk of prediabetes were also significant among male, urban, and rural residents (both P for trend <0.05), and the interactions between sex and blood pressure showed significant associations for risk of prediabetes and IGT (both P for interaction <0.05). Conclusions:Higher blood pressure levels were associated with an increased risk of prediabetes. The association with prediabetes was stronger in males, but no significant difference was found between urban and rural residents. More distinctive and effective prevention and control strategies should be developed for different populations.