Seasonal variation in the incidence of ruptured abdominal aortic aneurysm.

In order to determine any possible influence of climatic variables on the incidence of abdominal aortic aneurysm rupture, we reviewed 49,144 autopsies performed in two major hospitals in Rome, Italy, from January 1956 to March 1986. There were 297 subjects who were found to be sufferers of atherosclerotic abdominal aortic aneurysm for a prevalence of 0.6%. The aneurysm was intact in 220 cases (74%) and ruptured in 77 cases (26%). The highest incidence of ruptured aneurysm occurred during the Autumn and in the months May and July. The incidence of ruptured aneurysm was highest in case of significant changes of the atmospheric temperature. There was no correlation between the incidence of ruptured aneurysm and barometric pressure or humidity.