OBJECTIVE: To find out whether coronary atherosclerotic lesions and their precursors in male adolescents are associated with the amount of mesenteric and omental fat. SUBJECTS: A series of 40 forensic autopsy cases of ante-mortem healthy boys of 13-19 y of age were investigated. METHODS: Body height and weight, waist and hip circumferences and the thickness of the abdominal subcutaneous fat were measured, the body mass index (BMI) and waist-to-hip ratio (WHR) were calculated, and omental and mesenteric fat deposits were weighed. The intimal surface of the coronary arteries covered by lesions was measured by planimetry, and the thickness of the intima was measured by computerized image analysis. Intimal macrophage foam cells and smooth muscle cells were detected by immunohistochemisty, and macrophages were quantified. RESULTS: The intima thickness of the left anterior descending artery (LAD) and in the thickest lesion varied significantly across the tertiles of visceral fat when adjusted for age, being highest when the sum weight of omental and mesenteric fat exceeded 358 g. The intima thickness of the circumflex artery (CX) varied significantly across the tertiles of waist circumference when adjusted for age. No statistically significant associations with other indicators of obesity were found. Macrophage foam cells were present in the lesions and their maximal density/mm(2) correlated significantly with intima thickness in the LAD and CX. The maximal density of macrophages in CX and the right coronary artery (RCA) and in the thickest lesion varied significantly across the tertiles of visceral fat when adjusted for age, being highest when the amount of fat exceeded 358 g. The macrophage density also varied significantly across the tertiles of waist circumference in all vessels. CONCLUSIONS: The results indicate that early macrophage-rich coronary lesions are associated with increased amounts of visceral fat in adolescent male individuals. This emphasizes the importance of effective prevention of weight gain in individuals with a tendency to accumulate visceral fat at an early age.