Development of atherosclerosis over a 25 year period: an epidemiological autopsy study in males of 11 towns

We conducted an analysis of the data from two epidemiological autopsy studies of atherosclerosis in men aged 20–59 years in 1963–66 (the first study, 7470 cases) and in 1985–88 (the second study, 9600 cases). The investigations were performed in accordance with a special program of the World Health Organization in 11 town populations: Ashkhabad (Turkmenistan), Bishkek (Kirgizstan), Irkutsk and Yakutsk (Russia), Malmo (Sweden), Prague (Czech Republic), Riga (Latvia), Tallinn and Tartu (Estonia), and Kharkov and Yalta (Ukraine). Native and non-native populations were studied separately in Ashkhabad, Bishkek, and Yakutsk. Atherosclerosis was studied by the visual morphometrical method in the descending thoracic aorta, abdominal aorta and three main coronary arteries. In each vessel the prevalence and extent (percent of intimal surface) of fatty streaks, fibrous plaques, complicated, calcified and also raised lesions (all lesions except fatty streaks) were determined. Coronary stenosis was estimated in arteries as narrowed by more than 50%. Accelerated development of coronary atherosclerosis, especially in the 40–59 year age group, was noted in the second study in the male populations of most towns except Prague and Malmo. In Prague the extent of raised lesions in coronary arteries was practically the same in both studies, in Malmo it decreased in the second study. Aortic atherosclerosis also accelerated the rate of progression in all towns except Prague, where significant differences were not observed between the studies. Accelerated development of atherosclerosis in male populations from towns of Asia was combined with an increase of fatty streaks in all vessels, while in European populations it was not so obvious. In the native populations of Ashkhabad, Bishkek and Yakutsk, atherosclerosis was much less than in non-natives in both studies. In natives of these towns, accelerated development of atherosclerosis begins only from 40 years, in non-natives from 30. For the second study, there was typically an increase of the prevalence and extent of calcified lesions that were combined with an increased prevalence of coronary stenosis in all towns. The average percentage of stenosis in the coronary left anterior descending artery for men of 40–59 years of age was 12% in the first study and 24.9% in the second; for the coronary right artery, 7.4 and 13.8%, respectively. In accordance with findings of more severe atherosclerosis in males in most towns in the second