The effects of seasonal variations and weather conditions on the occurrence of heart attacks in Hungary between 2000-2004

INTRODUCTION: The onset of acute myocardial infarct shows circadian and seasonal variations, that are influenced by sex, age and the changes of weather conditions as well. AIM: The purpose of our present study is to investigate whether a seasonal variation can be found in the onset of myocardial infarctions during the period under investigation, and whether certain meteorological factors (air temperature, atmospheric pressure, front movements) influence the incidence of myocardial infarction. METHODS: Retrospective analysis has been carried out on patients admitted because of acute myocardial infarct in Hungary between 2000 and 2004 ( n=81.956). Data have been taken from the database of the National Health Insurance Fund Administration based on the International Classification of Diseases (ICD). Weather related data were provided by the National Meteorology Service. RESULTS: Regarding seasonal distribution the peak incidence period of acute myocardial infarct was spring, whereas the lowest number of events was observed during the summer months. There was a marked difference in the number of events per season ( p<0.001). A medium level negative correlation was found between the monthly average temperature and the occurrence of heart attack ( r=-0.404) during the period examined. A positive correlation was shown between front movements and the of number of events per season ( r=0.053). CONCLUSION: Our findings show that certain meteorological factors may be related to the onset of acute myocardial infarct, however, a number of other factors may also play an important role.