RESUMO
To explore the association between particulate matter (PM) and daily hospital visits of coronary heart diseases in Ningbo.Daily data of hospital visits from January 2014 to June 2015 (516 days in total) were obtained from the Yinzhou Health Information System in Ningbo. Daily air pollution data for PM and meteorological data were collected from the database of Ningbo Environmental Monitoring Center and Ningbo Meteorological Bureau. Time-series analysis by quasi-Poisson generalized additive model was used to examine the association between air pollution and hospital visits for coronary heart diseases by adjustment of long-term trends, seasonal patterns and meteorological variables (temperature, humidity), and day of week.An increase of an IQR of PMaccounted for 1.98% (95%:-0.59%-4.63%) increase of hospital visits for coronary heart diseases. The associations between PMand hospital visits for coronary heart diseases among female and the elderly (≥75 years) were stronger (=2.70%,95%:0.01%-5.47%;=3.35%, 95%0.12%-6.69%). The effects of PMattenuated after adjustment for PMPMhad short-term effects on daily hospital visits for coronary heart diseases in Ningbo, and such association was stronger among female and the elderly.