Prospective study of hemostatic factors and incidence of coronary heart disease: the Atherosclerosis Risk in Communities (ARIC) Study.

BACKGROUND: Although hemostatic factors contribute to acute coronary syndromes and atherogenesis, few studies have prospectively evaluated the association between multiple hemostatic factors and coronary heart disease incidence. METHODS AND
RESULTS: The Atherosclerosis Risk in Communities Study recruited 14,477 adults from 45 to 64 years of age who were initially free of coronary heart disease. Coronary disease risk factors and several plasma hemostatic factors were measured, and incidence of coronary heart disease was ascertained during an average follow-up of 5.2 years. Age-, race-, and field center-adjusted relative risks of coronary heart disease were significantly elevated (P < or = .05) per higher value of fibrinogen (relative risk: men, 1.76; women, 1.54), white blood cell count (men, 1.68; women, 2.23), factor VIII coagulant activity (women, 1.25), and von Willebrand factor antigen (men, 1.20; women, 1.18). Adjustment for other risk factors attenuated these associations for fibrinogen (adjusted relative risk: men, 1.48; women, 1.21), and it eliminated the white blood cell count, factor VIII, and von Willebrand factor associations, consistent with the other risk factors either confounding or partly operating through their effects on the hemostatic variables. Adjusted standardized relative risks of total mortality, ranging from 1.13 to 1.37, were also elevated (P < .05) in relation to these four factors. There was no association of coronary disease incidence with factor VII, protein C, antithrombin III, or platelet count.
CONCLUSIONS: Elevated levels of fibrinogen, white blood cell count, factor VIII, and von Willebrand factor are risk factors and may play causative roles in coronary heart disease. However, their measurement in healthy adults appears to add little to prediction of coronary events beyond that of more established risk factors.