Cough, Chest Stuffiness And Short-term Effects In Patients Outpatients PM2.5

Background Beijing, the capital of China has some of the highest levels of air pollution in the world. Recent epidemiological studies have shown an association between increased exposure of ambient particulate matter (PM) and adverse health effects in respiratory and cardiovascular systems.Aim We aimed to investigate the association between daily concentrations of fine particles with visits for cough and heartache conditions in Beijing.Methods The data of daily outpatient visits of Guangan’men hospital were extracted from the hospital electronic database from November1,2011to March31,2013. Since the records of PM2.5varied from time to time, the average daily PM2.5were used in our study. The average daily temperature, dew point, relative humidity, air pressure, visibility, wind speed were also collected from daily weather report by Chinese Meteorological Administration. The daily PM2.5concentrations were also from November1,2011to March31,2013obtained from American Embassy. Time series of semi-parametric generalized additive Poisson regression model were fitted to estimate associations of PM2.5with daily counts of outpatient visits for heartache and cough diseases. We used smoothing function control time sequence of the long-term trend, seasonal and meteorological factors and other confounding factors. We chose0to5days as the lag time for analysis, then determined which lag time of PM2.5concentrations affect the outpatient visits most in the model, calculated when PM2.5concentrations increased10ug/m3, the relative risk (RR) and95%CI of daily outpatient visits.Results A total of517days are collected in our study. According to Spearman correlation analysis, PM2.5is significant positively related with dew point, humidity, while has significant negative correlation with visibility, wind speed.(P<0.05) PM2.5like our study with the maximum PM2.5concentration reaching491g/m3and average concentration reaching96.99g/m3. We found significant associations between PM2.5and heartache visits. The first day (RR=1.007,95%CI=1.003-1.012, P=0.003), the second day (RR=1.005,95%CI=1.001-1.009, P=0.021)。An increase of10ug/m3in PM2.5was associated with the increasing heartache visits by0.743%(95%CI:0.265,1.221%) on the first day and0.486%(95%CI:0.074,0.897%) on the second day. PM2.5is significantly associated with cough visits, the first day(RR=0.998,95%CI=0.9971-0.9995, P<0.001), the fifth day (RR=1.002,95%CI=1.001-1.003, P<0.001) and have lag effect. An increase of10ug/m3in PM2.5was associated with the decreasing cough visits by0.168%(95%CI:0.049,0.286%) on the first day while the increasing cough visits by0.173%(95%CI:0.082,0.264%) on the fifth day.Conclusion PM2.5had significant simultaneous effect on cardiovascular outpatient visits while lag effect on respiratory visits in Beijing.