Influence Of Meteorological Factors On The Admissions And Readmissions Of Chronic Heart Failure Patients

Objective:To analysis the temporal variability of admission and readmission of patients with chronic heart failure of two-large scale comprehensive Grade 3A hospitals of Tianjin,and to investigate the main meteorological factors in patients with CHF,in order to take effective countermeasures.Methods:Collect the complete clinic datas of patients with CHF who admitted to Cadres Health Department of General Hospital of Tianjin Medical University and Cardiology Department of The Second Hospital of Tianjin Medical University between Jan. 2010 and Dec.2013.Summary the temporal variability of admission and readmission of patients with CHF,and compare the difference by gender,age,cardiac function and complications,analysis the relationship of them and meteorological factors including temperature,pressure,wind speed and relative humidity,investigate the effect of temperature on the admission and readmission of patients with CHF.Results:There are no significant increase of CHF by year.For seasons,spring is the highest rate of admissions for 32.4%,there are difference between males and females(P=0.013),especially for summer and winter;the occurrence of pneumonia in winter is highest than the other seasons(P<0.05);in addition,the different rates between seasons have relationship with cardiac function(P<0.01).Males and females,in all age groups, cardiac function, atrial fibrillation and pneumonia observed variability rates of admission among months(P<0.05).Variation of week on Monday admitted cases show the most.Readmission rates of CHF generally increasing year by year; and have seasonal variability(P<0.05),autumn is the highest season;week of variability is also exist(P=0.014),there are the most admission rates on Friday,the least on Sunday.CHF monthly average admitted cases and monthly meteorological factors are correlated,with the sudden change of temperature,diurnal, average wind are positive correlated(r=0.734,P=0.007;r=0.985,P=0.000;r=0.914,P=0.000); with the average with average relative humidity are negative correlated(r=-0.839,P=0.001).Weekly average admitted cases with the weekly sudden change of temperature, average wind are positive correlated( r=0.188,P=0.007;r=0.221,P=0.001), with average relative humidity are negative correlated(r=-0.152,P=0.028);age,gender, cardiac function and complications monthly and weekly admitted cases with the same period meteorological factors correlation are different.The presence of weekly readmission cases with the average temperature,maximum temperature and minimum temperature are positive correlated(rs =0.203,P=0.003;rs =0.192,P=0.006; rs =0.204,P=0.003), with the weekly sudden change of temperature are negative correlated(rs =-0.164,P=0.018).Daily admission cases with the minimum temperature, average relative humidity are negative correlated(r=-0.059,P=0.025;r=-0.052,P=0.048),with the sudden change of temperature,diurnal, average wind are positive correlated(r=0.060,P=0.022;r=0.057,P=0.029;r=0.055,P=0.036).The variable temperature difference between day time admitted cases is statistically significant(F =4.348,P=0.037).The 4th and 5th day after cooling under different cooling grades the admitted cases of CHF is statistically significant(P<0.05),the admitted cases are increase significant under the cooling grade-7.1~-2.40℃ than-0.60~0℃(P<0.05); The 2th~5th day after warming under different warming grades the admitted cases of HF is statistically significant(P<0.05), the higher warming grades the more admitted cases, the admitted cases are increase significant under the c warming grade 0.60~1.20℃ and 2.1~6.1℃ than 0~0.60℃(P<0.05);there is statistically significant among different warming grade and the readmission rates(P<0.05),when the warming grade range 0.60~1.20 ℃,the readmission rates for patients is highest(28.1%).Conclusion:There are variabilities among year,month and week of the admission and readmission of patients with CHF,the correlation between admitted cases and the same period meteorological factors are different, the variable temperature effect is significant,the different warming and cooling grade have different influence on the admission and readmission of patients,concerned about the weather change protective measures should be well done ahead of.