Risk Factors and Progression of Atherosclerosis in Youth: PDAY Study

The PDAY (Pathological Determinants of Atherosclerosis in Youth) study systematically examined the aortas and coronary arteries of approximately 3,000 autopsied young Americans (ages 15–34) who died from external causes (accidents, homicides, suicides), quantifying the presence, extent, and severity of atherosclerotic lesions by risk factor exposure.

Atherosclerotic lesions — fatty streaks in the aorta — were present in virtually all teenagers; raised plaques (fibrous caps with lipid cores) appeared in coronary arteries in the 15–24 age range and advanced progressively. Risk factors associated with accelerated lesion development included elevated serum cholesterol and LDL-C, hypertension, smoking, obesity, and hyperglycemia — the same risk factors that predict clinical events in adults. Males had more severe lesions than females at all ages.

The PDAY autopsy data established a fundamental epidemiological fact: coronary atherosclerosis begins in the second decade of life and progresses silently through the 20s and 30s under the influence of modifiable risk factors. By the time clinical events occur in the 40s–60s, decades of plaque accumulation have already occurred.

The clinical implication for prevention is stark. Waiting until midlife to assess and treat cardiovascular risk forfeits the decades when plaque is most nascent and most responsive to risk factor modification. The PDAY data provide the biological foundation for primordial prevention strategies — starting cardiovascular risk reduction in childhood and young adulthood rather than after risk scores or clinical events first appear.

We rate the evidence strong for autopsy data. The PDAY study establishing that coronary atherosclerosis begins in adolescence and advances under standard cardiovascular risk factors — foundational evidence that atherosclerosis is a disease of decades, not of midlife, supporting early and primordial prevention approaches.