Impact Of Shenzhen Meteorological Factors On The Risk Of OHCA Of Presumed Cardiac Etiology

Objective:To explore the correlation between meteorological factors and the number of out-of-hospital cardiac arrest(OHCA)of presumed cardiac etiology in emergency data,with a view to providing guidance on the allocation of emergency resources in Shenzhen and the adoption of comprehensive measures.Methods:The meteorological data in Shenzhen from 2013 to 2017 and 120 first-aid data of the same period were collected.The basic situation and time distribution of the collected data were statistically described.The correlation between meteorological factors were analyzed by Spearman rank correlation analysis.The nonlinear and lag effects of meteorological factors on the number of first-aid cases for OHCA of presumed cardiac etiology was explored using a generalized linear model combined with a distributed lag nonlinear model.The total accumulation lag 3D graph,overall cumulative lag graph for 7 days,the single-day exposure and the cumulative exposure effect graph for meteorological factors were plotted.The association stratified by sex or age(18～44 years,45～64 years and≥65 years)was also examined.Results:1.The total number of OHCA first-aid cases in Shenzhen from 2013 to 2017was 12,940,and the number of OHCA of presumed cardiac etiology first-aid cases for five years was 9,563.There were both no statistically significant change in the year trends.OHCA of presumed cardiac etiology fluctuates around 74%of the total OHCA incidence each year.The average age of the study subjects was 59±21 years,and the age group was mainly in people aged 65 and above,accounting for 42.67%of the entire population.The number of males patients was 2.44 times the number of females patients.2.There is a strong negative correlation between daily average pressure and daily average temperature(r_s=-0.848,P<0.01),and the correlation between other meteorological variables is weak.3.The results of single factor analysis showed that low temperature(RR=1.469,95%CI:1.259～1.714),low humidity(RR=1.170,95%CI:1.067～1.282),short sunshine duration(RR=1.047,95%CI:1.015～1.080),high air pressure(RR=1.195,95%CI:1.053～1.358),high humidity(RR=1.016,95%CI:1.000～1.031),high wind speed(RR=1.031,95%CI:1.008～1.056)and long sunshine duration(RR=1.162,95%CI:1.002～1.349)have dangerous effects on the occurrence of OHCA of presumed cardiac etiology.Convesely,high temperature(RR=0.959,95%CI:0.923～0.997)has a protective effect on the occurrence of OHCA.4.Multivariate analysis results showed that low temperature(RR=1.501,95%CI:1.276～1.764),high pressure(RR=1.183,95%CI:1.030～1.360),low humidity(RR=1.145,95%CI:1.041～1.260),high humidity(RR=1.138,95%CI:1.026～1.263),high wind speed(RR=1.033,95%CI:1.009～1.057),short sunshine duration(RR=1.048,95%CI:1.015～1.082)and long sunshine duration(RR=1.178,95%CI:1.012～1.372)showed dangerous effects on the occurrence of OHCA of presumed cardiac etiology,and high temperature(RR=0.970,95%CI:0.940～1.000)showed a protection effect on the occurrence of OHCA of presumed cardiac etiology.5.The results of the subgroup analysis showed that low temperature,low humidity,short sunshine duration,high humidity,high wind speed,long sunshine duration and high air pressure have dangerous effects on men;low temperature,low humidity,high humidity and high wind speed have dangerous effects on women,and high temperature has a protective effect on women;low temperature,low wind speed,high wind speed,short sunshine duration and high air pressure have dangerous effects on people aged 18to 44;Low temperature,high wind speed and low air pressure have dangerous effects on the 45-64 age group;low temperature,low humidity and long sunshine duration have dangerous effects on people aged≥65 years,and high temperature has a protective effect on people≥65 years old.Conclusion:The amount of OHCA first aid of presumed cardiac etiology in Shenzhen has not changed much from 2013 to 2017.There are far more male patients than female patients,mainly concentrated in the age group of 65 years and above.Low temperature is a significant risk factor for OHCA of presumed cardiac etiology and has a lag effect.Related management departments and medical institutions should take corresponding measures to optimize the emergency resource allocation and reduce the fatality rate of OHCA according to the meteorological warning.