Progression of carotid atherosclerosis. Three year follow-up and analysis of risk factors

OBJECTIVE: To elicit the risk factors associated with increasing grades of stenosis in patients with carotid plaque. STUDY DESIGN: Retrospective review of serial duplex scans of the carotid bifurcation. Case note review for documented risk factors. SETTING: Irvine Laboratory of the Academic Department of Surgery, Vascular Section. PATIENTS AND RESULTS: Review of serial duplex scans of the carotid bifurcation was performed on 200 unselected patients who each had a follow-up of at least three years. Definite progression of carotid atherosclerosis was defined as an unequivocal increase in at least one grade by the criteria of Strandness, and was documented in 50 patients (25%). Even if the initial situation is normal or minimal disease (< 15% stenosis), once definite plaque progression is observed, the lesion will progress to a hemodynamically significant one (> 50%) in 67% of this patient population. The only risk factor for plaque progression that we defined is hypertension, and this may be spurious. There are no risk factors associated with the subgroup of plaques that progress rapidly above those that progress at a slower rate. CONCLUSIONS: There are no risk factors defined in this population which are associated with advancing carotid atherosclerosis.