[Effect of Diurnal Temperature Range on the Number of Residents Hospitalized Due to Stroke in Lanzhou]

Objective To analyze the relationship between diurnal temperature range (DTR) and the hospitalization of stroke in Lanzhou,so as to provide a scientific basis for probing into the mechanism of temperature changes in inducing stroke and formulating comprehensive prevention and control measures for stroke by relevant departments.Methods The information of the patients hospitalized due to stroke in Lanzhou during January 2014 to December 2019 and the air pollutants (PM₁₀,SO₂,and NO₂) and meteorological data in the same period were collected for statistical analysis.Spearman rank correlation analysis was performed to analyze the correlations between air pollutants and meteorological factors.The distributed lag nonlinear model was adopted to fit the relationship between DTR and the number of stroke inpatients,and three-dimensional diagrams and the correlation diagrams of DTR against stroke risk were established.The stratified analysis was performed according to gender and age (< 65 years and ≥65 years).Results From 2014 to 2019,a total of 92 812 stroke patients were hospitalized in Lanzhou,with a male-to-female ratio of 1.35:1.There was a nonlinear relationship between DTR and the number of stroke inpatients in Lanzhou,which presented a lag effect.The low DTR at 4.5 ℃ had the largest RR value of 1.25 (95%CI=1.16-1.35) for stroke inpatients at a cumulative lag of 18 d.The effect of high DTR (18.5 ℃) on the hospitalization of stroke patients peaked at a cumulative lag of 21 d,with an RR value of 1.09 (95%CI=1.01-1.18).The stratified analysis results suggested that low levels of DTR had greater effects on the hospitalization of male stroke patients and stroke patients <65 years.Conclusions Short-term exposure to different levels of DTR had an impact on the number of stroke inpatients,and low levels of DTR had a slightly greater impact on stroke inpatients than high levels of DTR.Importance should be attached to the protection of males and people aged <65 years at low levels of DTR.