title: Associations of particulate matter with stroke mortality: a multicity study in Japan.
abstract: OBJECTIVE
  Evidence linking short-term exposure to outdoor air pollution with hemorrhagic stroke is inconclusive.
  
  
  METHODS
  We evaluated the effects of suspended particulate matter (SPM) on cardiovascular disease mortality, focusing on types of stroke, from March 2005 to December 2010, in five selected prefectures in western Japan. A multicity time-series analysis was used, and Asian dust was adjusted in the models.
  
  
  RESULTS
  Even after adjusting for Asian dust, the same-day SPM was positively associated with several types of stroke mortality. Following a 10-μg/m increase in SPM, rate ratios were 1.014 (90% confidence interval [CI]: 1.002 to 1.026) for stroke, 1.030 (90% CI: 1.004 to 1.056) for intracerebral hemorrhage, and 1.016 (90% CI: 1.003 to 1.030) for ischemic stroke mortality.
  
  
  CONCLUSIONS
  Short-term exposure to outdoor air pollution may increase the risks of hemorrhagic stroke as well as ischemic stroke mortality.
authors.affiliation: Department of Human Ecology, Okayama University Graduate School of Environmental and Life Science, Kita-ku, Okayama, Japan. yorichan@md.okayama-u.ac.jp
authors.forename: Takashi
authors.initials: T
authors.lastname: Yorifuji
authors.forename: Saori
authors.initials: S
authors.lastname: Kashima
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000393:Air Pollutants / Q000009:adverse effects* / Q000032:analysis; D000397:Air Pollution / Q000009:adverse effects* / Q000032:analysis / Q000706:statistics & numerical data; D004781:Environmental Exposure / Q000009:adverse effects* / Q000032:analysis / Q000706:statistics & numerical data; D006801:Humans; D007564:Japan / Q000453:epidemiology; D015233:Models, Statistical; D052638:Particulate Matter / Q000009:adverse effects* / Q000032:analysis; D016012:Poisson Distribution; D012044:Regression Analysis; D020521:Stroke / Q000209:etiology* / Q000401:mortality; D014504:Urban Health / Q000706:statistics & numerical data*
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter