Fine particulate air pollution and outpatient department visits for headache in Taipei, Taiwan

[[abstract]]This study was undertaken to determine whether there was an association between fine particle matter (PM2.5) levels and daily outpatient department visits (OPD) for headaches in Taipei, Taiwan. Daily OPD visits for headaches and ambient air pollution data for Taipei were obtained for the period 2006-2011. The relative risk of visits for OPD headaches 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 OPD visits for headaches were significantly associated with levels of PM2.5 both on warm days (>23 degrees C) and cool days (