Urban air pollution and emergency admissions for cerebrovascular diseases in Taipei, Taiwan

Aims This study was designed to evaluate the association between urban air pollutants and emergency admissions for cerebrovascular diseases. Methods and results Daily emergency admissions for cerebrovascular diseases (ICD-9-CM, 430-437) to the National Taiwan University Hospital were regressed against daily concentrations of carbon monoxide (CO), nitrogen dioxide (NO2), sulphur dioxide (SO2), ozone (O-3), and particulate matters with aerodynamic diameter < 2.5 (PM2.5) and 10 mu m (PM10) from 12 April 1997 to 31 December 2002 in Taipei metropolitan areas by the Poisson regression models adjusting for meteorological conditions and temporal trends. Single-pollutant models showed O-3 lagged 0 day, CO lagged 2 days, and PM2.5 and PM10 lagged 3 days were significantly associated with increasing emergency admissions for cerebrovascular diseases and CO lagged 2 days was significantly associated with increasing emergency admissions for strokes (ICD-9-CM, 430-434). Such association remained significant for O-3, CO, and cerebrovascular admissions after adjusting for PM2.5 and PM10 in two-pollutant models. The odds ratios were 1.021-1.022 per 31.3 ppb O-3 and 1.023-1.031 per 0.8 ppm CO, respectively. However, only CO was significantly associated with emergency admissions for stroke in the three-pollutant models with CO, O-3, and PM2.5 or PM10. Conclusion Emergency admissions for cerebrovascular diseases among adults were positively associated with increasing urban air pollution levels of O-3 lagged 0 day and CO lagged 2 days in Taipei.