Development of coronary heart disease in familial hypercholesterolemia.

We studied the development of coronary artery disease in 10 homozygous and 692 heterozygous patients with familial hypercholesterolemia. Seventy-five (22%) male heterozygotes and 35 (10%) female heterozygotes were affected by myocardial infarction, which was first noted in men in the 3rd decade of life and in women in the 4th decade of life. Thirty-eight (70%) out of the deceased 54 heterozygous patients died of coronary heart disease. The mean age at death was significantly less in male heterozygotes (54 years) than in female heterozygotes (69 years). Five homozygous and 105 male and 56 female heterozygous patients received coronary angiographic evaluation. The regression equations between age (X) and coronary stenosis index (Y) obtained by assigning score (0 to 5) to each of 15 coronary artery segments were Y = 1.57X - 20.43 (r = 0.956, p less than 0.05) in the homozygotes, Y = 0.52X - 9.11 (r = 0.438, p less than 0.001) in the male heterozygotes, and Y = 0.47X - 12.54 (r = 0.343, p less than 0.01) in the female heterozygotes. From these data, we can assume that coronary artery stenosis detectable by angiography will occur after 17 and 25 years of age in male and female heterozygotes, respectively, and the treatment of heterozygotes with lipid-lowering drugs can be delayed until late adolescence.