Independent influences of extreme atmospheric pressure on hypertension-related ER visits

Frequent emergency room (ER) visits occur for acute symptoms of hypertension or related complications in Beijing, China. Among the meteorological variables, atmospheric pressure directly relates to weather conditions and is hardly affected by artificial factors. In the studies of weather conditions and hypertension-related risks, atmospheric pressure is rarely found in literatures. Based on records of ER visit related to hypertension from three major hospitals in Beijing, from 2008 to 2012, the daily maximum (P-max) and minimum (P-min) atmospheric pressures were investigated in this study to identify the influences of air pressure on ER visits. Advanced time series models were utilized in quantifying their associations. In addition, major air pollutants and other meteorological variables including temperature, solar duration, and humidity were incorporated in the multivariate models to reveal the independent association between atmospheric pressure and ER visits. The results indicated the following: 1. The number of ER visits positively correlates with all atmospheric pressure metrics in both bivariate and partial correlation analyses. 2. The estimated relative risk (RR) corresponding to 1 hPa change inP(max)indicated a significant effect (P-max= 1029 hPa, RR = 1.107, 95% CIs: 1.034-1.185) from highP(max)on short lag terms. RR for males and the elders grew prominently at lag 1 d, whereas females responded toP(max)at lag 4 d. 3. The middle-aged group (45-65 years) was threatened by extremely lowP(min)with one day lag. 4. As for young (< 45 years) hypertensive patients, no effect from atmospheric pressure was identified. This study may provide new evidence that extreme atmospheric pressure is an independent inducer of hypertension-related symptoms or complications.