Recent trends in the prevalence of coronary disease: A population-based autopsy study of nonnatural deaths

Background: Despite increases in obesity and diabetes mellitus, mortality caused by coronary disease continues to decline. Recent trends in coronary disease prevalence are unknown. Methods: There were 3237 deaths among Olmsted County, Minnesota, residents aged 16 through 64 years during the 1981-2004 period. Of the 515 due to accident, suicide, homicide, or a manner that could not be determined, 425 individuals (82%) had coronary anatomy graded. Pathology reports were reviewed for the grade of coronary disease (range, 0-5) assigned each of 4 arteries: left anterior descending (LAD), left circumflex (LCx), right coronary artery (RCA), and left main artery (LMA). High-grade disease was defined as more than a 75% reduction in cross-sectional luminal area (grade ≥4) in any of LAD, LCx, or RCA or more than 50% reduction (grade ≥3) in LMA. Evidence of any disease was defined as a grade higher than 0 in any artery. Calendar-year trends were analyzed as linear and nonlinear functions. Results: Over the full period (1981-2004), 8.2% of the 425 individuals had high-grade disease, and 83% had evidence of any disease. Age- and sex-adjusted regression analyses revealed temporal declines over the full period (1981-2004) for high-grade disease, any disease, and grade of coronary disease. Declines in the grade of coronary disease ended after 1995 (P ≤ .01 for every artery) and possibly reversed after 2000 (P = .06 for LCx). Conclusions: Declines in coronary disease prevalence overall (during 1981-2004) reinforce arguments that any increased prevalence resulting from improved survival among persons with disease was offset by reductions in disease incidence. Study findings suggest that declines in coronary disease prevalence have ended. The question of whether recent trends are attributable to increasing obesity and diabetes mellitus awaits further investigation.