Cardiovascular risk factors for early carotid atherosclerosis in the general population: the Edinburgh Artery Study.

BACKGROUND

Recent attempts to identify cardiovascular risk factors affecting early-stage carotid atherosclerosis, measured by ultrasonographically assessed intima-media thickness, have been inconclusive.

OBJECTIVE

To study the relationship between traditional cardiovascular risk factors and intima-media thickness.

METHODS

Ultrasonic evaluation of the intima-media thickness of the common carotid artery was included in the 5-year follow-up examination of participants of the Edinburgh Artery Study. We had valid readings of intima-media thickness for 1106 men and women aged 60-80 years. Information on a range of cardiovascular risk factors had been collected during the baseline examination.

RESULTS

For men, in addition to age, lifetime smoking (measured in terms of pack years) was the only cardiovascular risk factor associated with increased intima-media thickness (P< or = 0.01) in the univariate analysis. Both systolic blood pressure (P < or = 0.001) and the high-density lipoprotein (HDL: total cholesterol ratio (P < or = 0.01) were correlated with intima-media thickness for women. When all the variables had been included in a multivariate analysis, pack years of smoking and the HDL:total cholesterol ratio were associated with early atherosclerotic development in men. In an equivalent analysis for women, alcohol consumption, systolic blood pressure and the HDL:total cholesterol ratio were associated with intima-media thickness.

CONCLUSION

These data suggest that risk factors affecting intima-media thickness differ for men and women. Further sex-specific analyses of prospective population studies are required in order to clarify the role of 'traditional' cardiovascular risk factors in the early stages of carotid atherosclerosis.