2950Cluster of climatic and pollutant characteristics increases admissions for acute myocardial infarction: analysis of 30,000 patients in a large metropolitan area

Abstract

Background: There is an intense scientific interest on how air pollution and climate change may affect environmental determinants of human health. Purpose(s): To study the impact of the combination of climate and air pollution features in the number of admissions, absolute and relative mortality due to acute myocardial infarction (MI) in 39 municipalities of Sao Paulo from 2012-2015. Method(s): Data about MI admissions were obtained from the Brazilian public health system (DataSUS). Daily information on weather were accessed from the BDMEP meteorological database. Additionally, daily information on air pollution were obtained from the CETESB database. A K-mean cluster analysis was applied for temperature, rainfall patterns, relative humidity of the air, nitrogen dioxide, particulate matter 2.5 and particulate matter 10. MI outcomes were compared among the clusters. Result(s): Data analysis produced 3 clusters: low temperature/ high pollution (n=194 days); intermediate temperature/intermediate pollution (n=416 days) and high temperature/low pollution (n=482). All atmospheric variables were significantly different among clusters (Figure 1A-B). As shown in Figure 1C, the combination of low temperature, dry weather and high pollution resulted in a significant increase in hospital admissions for MI (29.6+/-7.8 patients/day; P<0.01). This increase represents a mean difference of 2.1+/-0.60 patients day when compared with the intermediate cluster (P<0.01) and a mean increase of 1.8+/-0.7 patients/day (P=0.02) when compared with warmer temperatures/better air condition (absolute increase up to 400 MI cases over a period of 200 days). There was no significant difference for hospitalization between the intermediate temperature/ intermediate pollution and high temperature/low pollution groups (27.9+/-9.3 vs. 26.8+/-7.3; P=0.07). The differences in temperature and pollution did not result in higher mortality (P=0.13). Conclusion(s): The combination of atmospheric conditions with low temperature, dry weather and increased inhalable particles resulted in a marked increase of hospital admissions due to MI. (Figure presented).