[Association between the concentration of particulate matters and the hospital emergency room visits for circulatory diseases: a case-crossover study].

Objective To explore the association between the concentration of particulate matters with an aerodynamic diameter of <10 μm ( PM10 ) and the hospital emergency room visits for circulatory diseases ( International Classification of Diseases, tenth vision ICD-10 : 100-199) in Beijing, China. Methods We collected data for daily hospital emergency room visits of circulatory diseases ( ICD-10:I00-I99 ) from Peking University Third Hospital and from the ambient air PM10 through the Beijing Municipal Environmental Monitoring Center. A time-stratified case-crossover design was used to evaluate associations between circulatory disease health outcomes and PM10.Results The no-lagged unidirectional case-crossover design with 1:4 matched pairs had the highest odds ratios (ORs) between PM10 and the hospital emergency room visits for circulatory diseases. After adjusting the temperature and the relative humidity, a 10μg/m3 increased in the PM10 were found associated with the emergency room visits on value of ORs of 1.006(95% CI:1.003-1.008) for the total circulatory diseases ( ICD-10:I00-I99), 1.003 (95% CI:0.996-1.010) for coronary heart disease ( ICD-10:I20-I25 ), 1.005 ( 95 % CI:0.997-1.013 ) for cardiac arrhythmia ( ICE)-10:I47-I49), 1.019 (95 % CI:1.005-1.033 ) for heart failure disease ( ICD-10:I50 ),and 1.003 ( 95 % CI : 0.998-1.007 ) for cerebrovascular diseases ( ICD-10:I60-I69 ), respectively. Conclusion These findings suggested that elevated levels of ambient PM10 were positively associated with hospital emergency room visits for the total number of circulatory diseases and heart failure disease. Key words: Circulatory diseases;  Particulate matter;  Case-crossover study