Fine particulate air pollution and hospital admissions for congestive heart failure: a case-crossover study in Taipei

This study was undertaken to determine whether there was an association between fine particles (PM2.5) levels and hospital admissions for congestive heart failure (CHF) in Taipei, Taiwan. Hospital admissions for CHF and ambient air pollution data for Taipei were obtained for the period 2006-2010. The relative risk of hospital admissions was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality and long-term time trends. For the single pollutant model (without adjustment for other pollutants), increased CHF admissions were significantly associated with PM2.5 both on warm days (>23 degrees C) and cool days (<23 degrees C), with an interquartile range increase associated with a 13% (95% CI = 9-17%) and 3% (95% CI = 0-7%) increase in CHF admissions, respectively. In the two-pollutant models, PM2.5 remained significant after the inclusion of SO2 or O-3 both on warm and cool days. This study provides evidence that higher levels of PM2.5 increase the risk of hospital admissions for CHF.