Authors
Woodward M. Lowe GD. Rumley A. Tunstall-Pedoe H.
Institution
Cardiovascular Epidemiology Unit, University of Dundee, Scotland.
Title
Fibrinogen as a risk factor for coronary heart disease and
mortality in middle-aged men and women. The Scottish Heart
Health Study.
Source
European Heart Journal. 19(1):55-62, 1998 Jan.
Abstract
AIMS: Fibrinogen was measured in 5095 men and 4860 men aged
40-59 in a random population sample from 25 districts of Scotland recruited
during 1984-87: the Scottish Heart Health Study. Fibrinogen
was then related to the chance of fatal and non-fatal coronary events and
death from any cause during a subsequent follow-up period of around 8 years.
METHODS AND RESULTS: Fibrinogen was measured by the Clauss
assay. The effect of fibrinogen on coronary heart disease
and death was assessed through age-adjusted means and Cox proportional
hazards regression models, accounting for age, cotinine (a measure of tobacco
smoke inhalation) and 11 other major coronary risk factors.
Fibrinogen was found to be an important risk factor for
coronary heart disease in men and women, with and without pre-existing
coronary heart disease. There appears to be a threshold effect, with those in
the highest fifth of the distribution having a much increased risk. Estimated
age-adjusted hazard ratios by sex and pre-existing coronary heart disease
group for the highest to lowest fifth of fibrinogen range
between 1.93 and 4.86. Fibrinogen is also important as a
risk factor for coronary death and all-causes mortality,
with a similar threshold effect. Comparing the two extreme fifths, the hazard
ratios for coronary death are 3.01 and 3.42, and for all-cause
mortality are 2.59 and 2.20, for men and women respectively.
Adjustment for cotinine reduces the hazard ratios, but further adjustment for
the other 11 risk factors has little effect for coronary heart disease
events. After full adjustment there is a remaining significant (P < 0.05)
hazard ratio for coronary death and death from any cause and for a coronary
heart disease event for those free of coronary heart disease at baseline,
amongst men, comparing the highest to the lowest fifth. CONCLUSION:
Fibrinogen is a strong predictor of coronary heart disease,
fatal or non-fatal, new or recurrent, and of death from an unspecified cause,
for both men and women. Its effect is only partially attributable to other
coronary risk factors, the most important of which is smoking.