Accelerated coronary atherosclerosis not explained by traditional risk factors in 13% of young individuals

Importance: Most individuals who die of sudden cardiac death (SCD) display very advanced lesions of atherosclerosis in their coronary arteries. Thus, we sought to identify and characterize a putative subpopulation of young individuals exhibiting accelerated coronary artery atherosclerosis. Objective: Our analysis of the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) study—which examined 2651 individuals, obtaining quantitative measurements of traditional risk factors for coronary heart disease (CHD)—aimed to identify individuals with advanced coronary artery lesions, and to determine whether risk factors could account for such rapid disease progression, or not. Design: Using the cross-sectional PDAY study data, an exploratory de facto analysis stratified the population by age and observed number of coronary raised lesions and examined these groups via Poisson regression modeling. A separate de novo approach utilized Poisson mixture modeling to generate low- and high-growth groups based on measurements of traditional risk factors, and identified factors contributing to disease progression. Participants: Participants, n = 2651 individuals aged 15–34, who had died of non-cardiac death, were recruited post mortem. Tissues and other samples were harvested for analysis (details in previously published PDAY studies). Main Outcome(s) and Measure(s). Using quantitative measurements of raised coronary lesions and traditional risk factors of CHD, we sought to identify which risk factors account for disease progression. Results: A group of ~13% of the PDAY population exhibits accelerated coronary atherosclerosis despite their young age. Several traditional risk factors were associated with increased odds of inclusion in this subgroup, reflecting current understanding of these markers of disease. However, only age was a significant contributing factor to the observed coronary lesion burden. Conclusions: While a range of traditional risk factors contribute to an individual's inclusion to the identified subgroup with accelerated atherosclerosis, these factors, with the exceptions of age, are not able to predict an individual's lesion burden. Moreover, unattributed variances in o Short summary: Hypothesis The extent of coronary atherosclerotic disease is limited and homogeneous within youth, and its progression can be accounted for by traditional risk factors in this population. Findings: A subpopulation (~13%) of the Pathobiological Determinants of Atherosclerosis in Youth cohort exhibited accelerated coronary artery atherosclerosis. While several traditional risk factors contribute to an individual's inclusion in this subgroup, these factors, with the exceptions of age, do not predict accurately an individual's lesions burden. Critically, unattributed variances in observations indicate the need for the identification of novel risk factors. Meaning: Screening of the general population at a young age for high-risk group membership could provide opportunity for disease prevention and avoidance of the worse complications such as myocardial infarction and sudden cardiac death later in life.