Background: It is thought that biological responses to air pollutants affect various heart diseases, with the magnitude of the effect dependent on the specific disease. The short-term effects of fine particulate matter (PM(2.5)) on mortality for heart diseases were examined in 9 Japanese cities from 2002 to 2004.
Methods and results: Mortality data obtained from the Ministry of Health, Labour and Welfare of Japan and PM(2.5) data from the National Institute for Environmental Studies were used in a generalized linear model to evaluate the association between PM(2.5) concentration and the mortality, adjusted for ambient temperature, relative humidity, seasonality, and day of the week. The area-specific results were combined using meta-analysis with a random-effects model. Of 67,897 deaths from heart disease, a significantly positive association was observed between heart disease mortality and PM(2.5) at lag 0. In the age-stratified analyses, the effect of PM (2.5) on acute myocardial infarction, and cardiac arrhythmia and conduction disorders was stronger at lag 0 for the younger population (0-64 years). The associations were not clear in mortality of the elderly.
Conclusions: Positive associations between PM (2.5) and heart disease mortality in Japan were observed. The effects of PM(2.5) may vary by disease and age.