The impact of meteorological factors on the onset of myocardial infarction in the coastal region of middle Dalmatia.

The influence of mediterranean climate on the onset of acute myocardial infarction (AMI) has been investigated in a study group comprised of 1306 AMI patients from the coastal part of middle Dalmatia (Croatia) admitted to the two Split hospitals in the 1981-1987 period. AMI incidence during the southern wind (0.62 per day) was significantly greater than during the northern wind (0.50 per day; p < 0.05), as well as during all non-southern-wind days (0.49 per day; p < 0.01). The coefficients of partial correlation showed a significant association of AMI incidence with increased air temperature (p < 0.05) and relative humidity (p < 0.05). Cross-correlation showed a positive link of AMI incidence to increased air temperature four days before, and on the day of the incident (p < 0.05). Analysis of the synoptic situations revealed characteristics of unstable weather in the days with 4 or more AMI patients. The results suggest that during the southern wind or the passing atmospheric front, coronary patients should stay at home, avoid both physical and psychological stress, and take antianginal drugs more frequently.