The Study Of Effect Of High Temperature And Ozone On Hypertension

Objectives:1.Using statistical methods to analyze the meteorological data in summer of Shijiazhuang City from 2014 to 2017,and to explore the variation characteristics and distribution characteristics of high temperature heat waves and hot weather.2.Through the analysis of the ozone pollution in Shijiazhuang City from2014 to 2017 and the relationship with meteorological factors,we can understand the ozone pollution situation in Shijiazhuang City.3.We can understand the effects of high temperature and ozone on the daily outpatient volume of hypertension in Shijiazhuang City by analyzing the effects of high temperature and ozone on the amount of hypertension in four general hospitals in Shijiazhuang City.4.The effects of high temperature and ozone on hypertensive rats were investigated by simulating the effects of simple ozone exposure,high temperature and ozone exposure on rats.Methods:1.The main atmospheric pollutants,meteorological data and the amount of hypertension clinics in Shijiazhuang general hospitals in the summer of2014-2017 were collected.2.Analyze the correlative relationship between air pollutants and meteorological factors by using Spearman correlation coefficient.3.Analyze the effect of high temperature and ozone on the outpatient volume of hypertension by using the statistical analysis software Empower Stats.4.The comparison of biological indicators between the two groups of hypertensive rats was analyzed by analysis of variance.The comparison between the two groups was performed by t test.Then the LSD test and Dunnett'T3 test were used to compare the two groups.What was used to determine whether the difference had statistical significance is P<0.05Results:1.In the summer of 2014-2017,there were the highest number of hot weather days in Gaocheng District of Shijiazhuang City,reaching 81 days.The lowest number of hot weather days were in Xingtang County,reaching 39 days.In the summer of 2014-2017,heat wave of Shijiazhuang occurred frequently in Gaocheng District,Wuji County and Zhengding County.The extreme values of high temperature were?40?in 11 counties.Except for Xingtang County,the extreme values of high temperature in the other counties occurred in July 2017.In the summer of 2014 to2017,there was the highest number of one level of sultry in Gaocheng District of Shijiazhuang City,reaching 35 days.There was the least sweltering days in Pingshan County,which was 10 days.In the summer of 2014-2017,there was the highest number of secondary sultry days in Gaoyi County of Shijiazhuang City,88 days.The lowest number of secondary sultry days was in Jingxing County,reaching 51 days.The hot weather and sweltering weather in the past four years was mainly concentrated in 2017.2.Temperature and ozone changes showed that the minimum temperature and ozone appeared at 06:00-08:00,and the highest temperature and ozone appeared at15:00-17:00.The highest value of ozone lagged behind the highest temperature for one hour.The average daily temperature in urban and county areas was 26.77?and26.61?,respectively.The daily maximum temperature was 31.32?and 31.56?.The maximum 8-hour average concentration of ozone was 146.53?g/m³ and 157.68?g/m³,respectively,the 90th percentile ozone concentration in urban and county areas reached 210.54?g/m³ and 225.04?g/m³,respectively.3.There was a positive correlation between ozone and daily average temperature,daily maximum temperature,wind speed,and a negative correlation between ozone and relative humidity,air pressure.From 2014 to 2017,a total of 32772 cases of hypertension were diagnosed in four general hospitals,including 17068?52.08%?males and 15704 females?47.92%?.The daily outpatient volume of hypertension was positively correlated with daily maximum temperature,O₃ and SO₂,and negatively correlated with daily average relative humidity.4.The relationship between the daily outpatient volume and the O₃ exposure response showed that there was a linear relationship between the daily outpatient volume and the O₃ concentration.With the increase of O₃ concentration,the daily outpatient volume of hypertension increased.The highest temperature and O₃ effect on the daily outpatient volume of hypertension were positive,with RR of 1.0190?95%CI:1.0117,1.0490?and 1.0039?95%CI:1.0030,1.049?,respectively,and after adjusting for different covariates,the RR values of Model 1 and Model 2 increased.There was an interaction between O₃ and the daily maximum temperature during high temperature?P<0.05?.During non-high temperature period,there was no interaction between O₃ and daily maximum temperature?P?0.05?.5.Simple ozone exposure,combined exposure of ozone and high temperature all increased the body temperature and blood pressure of rats.Simple ozone exposure can increase the body weight and heart rate of rats,while high temperature and ozone exposure reduced the body weight and heart rate of rats.6.Simple ozone exposure,high temperature and ozone exposure increased the levels of inflammatory factors IL-6,sICAM-1,CRP,TNF-?in the plasma and myocardium of hypertensive rats.Pure ozone exposure,high temperature and ozone exposure increased the vasomotor factors Ang-II,ET-1 and NO in plasma of hypertensive rats.Ozone exposure,high temperature and ozone exposure increased cardiovascular risk factors LDL-C,TG and TC in the plasma of hypertensive rats,but reduced HDL-C.Pure ozone exposure,combined exposure of high temperature and ozone increased MDA,PAI-1,D2D,but decreased SOD of hypertensive rats.There were thickened myocardial fibers,uneven cytoplasmic staining,and blurred nuclear structure in myocardial tissue of hypertensive rats after experimental exposure.Conclusions:1.In the past four years,Shijiazhuang had a high number of hot days and sweltering days,mainly concentrated in 2017.2.The maximum 8-hour average concentration of ozone in summer days of Shijiazhuang City was close to the national air quality standard secondary limit?160?g/m³?,the 90th percentile ozone concentration exceeded the national air quality standard secondary limit,ozone pollution should not be ignored.There was a clear correlation between ozone and meteorological factors.3.The influence of high temperature and ozone in Shijiazhuang on the daily outpatient volume of high blood pressure in hospital was positive.4.The combination of high temperature and ozone activates the inflammatory system in the body,aggravates the inflammatory response of hypertension and induces the increase of vasoconstrictor in the body,causes the blood pressure to rise further and activates the oxidative stress reaction and causes the increase of blood lipids,which leads to the occurrence and development of hypertension complications.High temperature may enhance the adverse effects of ozone on hypertensive rats.5.High temperature and ozone can cause myocardial tissue structure changes in hypertensive rats,inflammatory reaction and oxidative damage of cardiomyocytes.