High coronary mortality in cold regions of Sweden.

The hypothesis that cold climate is associated with high coronary mortality in Sweden is tested. Cold exposure was calculated in each of the 284 municipalities of Sweden. There was a significant association between cold exposure and coronary mortality in both sexes in all age groups. The strongest association was found in men aged 40-64 years (coefficient of determination k = 0.39). The decile of men aged 40-64 years who lived in the coldest municipalities had a 40% excess mortality. A significant association was also found between cold exposure and mortality from cerebrovascular diseases. We conclude that there is a strong regional association between cold exposure and high coronary mortality.