Atherosclerosis and diabetes mellitus.

Diabetes mellitus occurred most frequently in Prague (8.4%) and Malmö (8.6%), and less often in Tallin (3.4%), Yalta (3.3%), and Ryazan (2.1%), these differences not being connected with differences in age distribution. The extent of raised and calcified lesions in the coronary arteries and calcified lesions in the aorta in the pure diabetes group was similar to that in the high atherosclerosis group and significantly higher than in the standardized average atherosclerosis group. Raised and calcified lesions in the aorta and raised lesions in the coronary arteries were more extensive in the diabetes group than in the high atherosclerosis group. In all diabetes groups, stenosis of the coronary arteries and myocardial lesions occurred much more frequently than in the average atherosclerosis group but were less common than in the high atherosclerosis group. Coronary thrombosis also occurred more frequently in the high atherosclerosis group. Diabetes per se and hypertension were found to have approximately the same effect on the development of atherosclerosis, but hypertension had a greater effect than diabetes on the development of aortic atherosclerosis. There were no significant differences in the frequency of coronary stenosis and myocardial lesions in diabetics and hypertensives. Diabetics of more than 10 years' standing generally showed more coronary but not more aortic atherosclerosis than those who had had diabetes for less than 10 years. In insulin-treated diabetics coronary atherosclerosis tended to be more extensive than in those treated by diet or by tablets, but there was no difference in the frequency of coronary stenosis and thrombosis and myocardial and cerebrovascular lesions.

Atherosclerosis and rheumatic heart disease.

The extent of aortic atherosclerosis in subjects with rheumatic heart diseases was similar to that in the standardized average atherosclerosis group of subjects. The extent of coronary atherosclerosis, particularly in men, was similar to that in the low atherosclerosis group. In the aorta, this finding was accounted for by the greater extent of complicated and raised lesions; in the coronary arteries, it was accounted for by the lesser extent of fibrous plaque. Coronary stenosis, fresh myocardial infarction, and large myocardial scar occurred much less frequently in rheumatic subjects than in the high atherosclerosis group. There was no difference in the frequency of stenosis between the rheumatic and low atherosclerosis groups.