Fibrinogen, viscosity, and white blood cell count are major risk factors for ischemic heart disease. The Caerphilly and Speedwell collaborative heart disease studies.

TLDR

Recent studies suggest that hemostatic factors and white blood cell count predict ischemic heart disease. The study examined the relationships of fibrinogen, viscosity, and white blood cell count with incident IHD in the Caerphilly and Speedwell prospective cohorts. Participants were followed for an average of 5.1 years in Caerphilly and 3.2 years in Speedwell, during which 251 major IHD events occurred. In a cohort of 4,860 men, the top quintile of fibrinogen, viscosity, and white blood cell count was associated with 4.1‑, 4.5‑, and 3.2‑fold higher odds of IHD, respectively, independent of smoking and conventional risk factors, and jointly these variables improved logistic regression fit and predicted IHD as well as traditional risk factor models.

Abstract

Recent studies have suggested that hemostatic factors and white blood cell count are predictive of ischemic heart disease (IHD). The relations of fibrinogen, viscosity, and white blood cell count to the incidence of IHD in the Caerphilly and Speedwell prospective studies are described.The two studies have a common core protocol and are based on a combined cohort of 4,860 middle-aged men from the general population. The first follow-up was at a nearly constant interval of 5.1 years in Caerphilly and 3.2 years in Speedwell; 251 major IHD events had occurred. Age-adjusted relative odds of IHD for men in the top 20% of the distribution compared with the bottom 20% were 4.1 (95% confidence interval, 2.6-6.5) for fibrinogen, 4.5 (95% confidence interval, 2.8-7.4) for viscosity, and 3.2 (95% confidence interval, 2.0-4.9) for white blood cell count. Associations with IHD were similar in men who had never smoked, exsmokers, and current smokers, and the results suggest that at least part of the effect of smoking on IHD is mediated through fibrinogen, viscosity, and white blood cell count. Multivariate analysis shows that white blood cell count is an independent risk factor for IHD as is either fibrinogen or viscosity, or possibly both. Jointly, these three variables significantly improve the fit of a logistic regression model containing all the main conventional risk factors. Further, a model including age, smoking habits, fibrinogen, viscosity, and white blood cell count predicts IHD as well as one in which the three hemostatic/rheological variables are replaced by total cholesterol, diastolic pressure, and body mass index.Jointly, fibrinogen, viscosity, and white blood cell count are important risk factors for IHD.