[Analysis on influencing factors of deaths from severe heat stroke in Shanghai, 2013-2017].

Objective: To explore the related factors of death from severe heat stroke in Shanghai from 2013 to 2017. Methods: The data of 1 152 patients with severe heat stroke who were divided into survival (n=1 037) and death (n=115) groups including gender, age and heat stroke type (heat cramp, heat exhaustion, heat apoplexy and the mixed type) were collected from meteorological bureau and case report system for high temperature heat stroke in Shanghai from 2013 to 2017. Meanwhile, the meteorological data of the onset date of severe heat stroke cases were collected, including maximum temperature, minimum temperature, daily temperature, relative humidity, air pressure, precipitation and wind speed. The differences of individual and meteorological factors between the two groups were compared, and multivariate logistic regression model was used to analyze the related factors of death from severe heat stroke. Results: Among 1 152 cases, the mean±SD of age was (56.29±18.95) years old, 843 (73.18%)were male, 962 (83.51%) were in the heat wave period; 322 cases (27.95%) were heat cramp, 170 cases (14.76%) were heat exhaustion, 533 cases (46.27%) were heat apoplexy and 114 cases (9.90%) were the mixed type. Daily average temperature ((32.81±1.99) ℃), daily maximum and minimum temperatures ((38.20±2.24) ℃ and (29.22±1.94) ℃) in survival group were lower than those in death group (all P values<0.001), which were (33.76±1.17) ℃, (39.19±1.31) ℃ and (29.72±1.66) ℃. Daily average relative humidity ((60.36±9.75)%) and daily minimum relative humidity ((41.26±9.71)%) in survival group were higher than those in death group(allP values <0.05), which were (54.59±6.89)% and (35.60±7.24)%. The results of logistic regression analysis suggested that compared with the cases with daily average humidity <60% and a mixed type heat stroke, the death OR (95%CI) values of cases with daily average humidity >60%, heat cramp, heat exhaustion and heat apoplexy were 0.31 (0.18,0.54), 0.13 (0.05,0.34), 0.68 (0.58,2.30) and 0.87 (0.48,1.58). Conclusion: The temperature, relative humidity and the type of heat stroke were the main related factors affecting the prognosis of severe heat stroke.