title: The association between fine particulate air pollution and hospital emergency room visits for cardiovascular diseases in Beijing, China.
abstract: BACKGROUND
  Because epidemiological studies have yielded different results, the association between exposure to fine particulate matter less than 2.5 microm in aerodynamic diameter (PM(2.5)) and acute events of cardiovascular diseases (CVD) is unknown. Additionally, no research has been conducted to explore the association between PM(2.5) and hospital emergency room (ER) visits of cardiovascular diseases in Beijing, China.
  
  
  OBJECTIVE
  To explore the association between PM(2.5) and the hospital ER visits in Beijing, China for CVD {(International Classification of Diseases, 10th vision (ICD-10): I00-I99)}.
  
  
  METHODS
  We collected data for daily hospital ER visits for CVD from the Peking University Third Hospital, daily ambient PM(2.5) data from a fixed monitor site at Peking University, and data on the daily level of gaseous air pollutants {sulfur dioxide (SO(2)) and nitrogen dioxide (NO(2))} from the Beijing Municipal Environmental Monitoring Center between June 1, 2004 and December 31, 2006. A time-stratified case-crossover design was used to evaluate associations between CVD health outcomes and ambient air pollutants.
  
  
  RESULTS
  8377 hospital ER visits of CVD were collected in our study. After adjusting the temperature and the relative humidity, the associations for 10 microg/m(3) increases in levels of PM(2.5), SO(2), or NO(2) and hospital ER visits for cardiovascular diseases were statistically significant with odds ratios (ORs) of 1.005{95% confidence interval (CI): 1.001-1.009}, 1.014(95% CI: 1.004-1.024), and 1.016(95% CI: 1.003-1.029), respectively.
  
  
  CONCLUSIONS
  These findings suggest that elevated levels of ambient air pollutants are associated with the increase in hospital ER visits for CVD in Beijing, China.
authors.affiliation: Department of Occupational and Environmental Health, Peking University School of Public Health, No 38, Xueyuan Road, Haidian District, Beijing 100191, China. guoyuming@yahoo.cn
authors.forename: Yuming
authors.initials: Y
authors.lastname: Guo
authors.forename: Yuping
authors.initials: Y
authors.lastname: Jia
authors.forename: Xiaochuan
authors.initials: X
authors.lastname: Pan
authors.forename: Liqun
authors.initials: L
authors.lastname: Liu
authors.forename: H-Erich
authors.initials: HE
authors.lastname: Wichmann
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D002318:Cardiovascular Diseases / Q000628:therapy*; D002681:China; D018592:Cross-Over Studies; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D006801:Humans; D010316:Particle Size; D014887:Weather
chemical_list: D000393:Air Pollutants