Continued high incidence of coronary artery disease at autopsy in Olmsted County, Minnesota, 1950 to 1979.
The autopsy records of all people over 30 years old who died and underwent autopsy in Olmsted County from 1950 through 1979 were reviewed (n = 5558, autopsy rate approximately 50%). The hearts of 530 subjects were reexamined for the severity of coronary artery disease and this determination was compared with the recorded grade. After both record and specimen the three major coronary arteries were graded according to percent reduction in luminal area (1 = 0 to 25%; 2 = 26% to 50%; 3 = 51% to 75%; 4 = 76% to 99%; 5 = occlusion). Grades 4 and 5 were designated as significant coronary disease (SCD), and 94% to 99% of diagnoses of SCD were confirmed on reexamination. The percentage of people with SCD increased during the period 1950 to 1969 and remained high in the 1970s. Cohort analysis showed an increase in the disease in all age groups (except in the 30- to 49-year-old group for the later decades of birth). There was no change in the prevalence of myocardial infarction scars over the study period.