Early lesions of atherosclerosis in childhood and youth: natural history and risk factors.

This paper traces the development of knowledge concerning early lesions of atherosclerosis and the relationship to risk factors in children, youth, and young adults. Autopsy studies have shown that atherosclerosis begins in childhood with the appearance of aortic fatty streaks. Aortic fatty streaks of some degree are present in practically all individuals from every human population. Coronary fatty streaks begin to form in adolescence. Most persons 20-29 years of age have coronary fatty streaks of some degree, regardless of sex, race, or national origin. While fatty streaking is clinically harmless and potentially reversible, progression to fibrous plaques and more advanced lesions often leads to a critical stage of atherosclerosis in which clinical disease develops. Development of fibrous plaques begins in the 20s. The most recent studies of atherosclerosis in youth and young adults provide additional details to establish the relationship of these lesions to serum lipids and lipoproteins and other identified risk factors for atherosclerosis and coronary heart disease in adults. One report shows that microscopic counterparts of fatty streaks occur in the left anterior descending coronary artery in the majority of children 10-14 years of age. Over 5% have more advanced microscopic lesions at this age. Autopsy studies of youth have shown that serum total cholesterol and low-density lipoprotein cholesterol levels are strongly related to aortic fatty streaks and the very-low-density lipoprotein cholesterol levels are positively correlated to coronary artery fatty streaks. Finally, a definitive report indicates that serum lipoprotein cholesterol concentrations and smoking are important determinants of the early stages of atherosclerosis in adolescents and young adults.