Polymorphisms in the factor VII gene and the risk of myocardial infarctionin patients with coronary artery disease

Background: High plasma levels of coagulation factor VII have been suggeste d to be predictors of death due to coronary artery disease. Since polymorph isms in the factor VII gene contribute to variations in factor VII levels, such polymorphisms may be associated with the risk of myocardial infarction , which is precipitated by thrombosis. Methods: We studied a total of 444 patients, 311 of whom had severe, angiog raphically documented coronary atherosclerosis. Of these 311 patients, 175 had documentation of a previous myocardial infarction. As a control group, 133 patients with normal coronary arteriograms were also included. We measu red the levels of activated factor VII and assessed three polymorphisms in the factor VII gene, one involving the promoter (A1 and A2 alleles), one in volving the catalytic region (R353Q), and one involving intron 7. Results: Each of the polymorphisms influenced factor VII levels. Patients w ith the A2A2 and QQ genotypes had the lowest levels of activated factor VII (66 percent and 72 percent lower, respectively, than the levels in patient s with the wild-type genotypes). The frequencies of the various genotypes i n the patients free of coronary artery disease were similar to those in the entire population of patients with coronary artery disease. In the latter group, there were significantly more heterozygotes and homozygotes for the A2 and Q alleles among those who had not had a myocardial infarction than a mong those who had had an infarction (P=0.008 for the presence of the promo ter polymorphism and P=0.01 for the presence of the R353Q polymorphism by c hi-square analysis). The adjusted odds ratio for myocardial infarction amon g the patients with the A1A2 or RQ genotype was 0.47 (95 percent confidence interval, 0.27 to 0.81). Conclusions: Our findings suggest that certain factor VII genotypes have a role in protection against myocardial infarction. This may explain why some patients do not have myocardial infarction despite the presence of severe coronary atherosclerosis. (N Engl J Med 2000;343:774-80.) (C) 2000, Massach usetts Medical Society.