Type-2 diabetes and carotid stenosis: a proposal for a screening strategy in asymptomatic patients

Abstract

The objective of this prospective observational study was to establish the prevalence of carotid atherosclerosis in an asymptomatic diabetic population and to determine predictive factors for a screening optimization. A total of 300 consecutive type-2 diabetic subjects (166 males, 134 females) underwent a physical examination and duplex carotid scanning. Patients with a recent cerebrovascular event (±6 weeks) or previous carotid surgery were excluded. The prevalence of carotid stenosis ≥60% or occlusion was 4.7%; the prevalence of carotid atherosclerosis was 68.3%. Risk factors for stenosis ≤60% or occlusion were the presence of diabetic retinopathy (OR: 3.62; 95% CI: 1.12-11.73), ankle-brachial index (ABI) <0.85 (OR: 3.94; 95% CI: 1.21-12.84) and a personal history of neurological disorders (OR: 4.54; 95% CI: 1.16-17.81). Being female was a protective factor (OR: 0.09; 95% CI: 0.01-0.78). The two factors in the analysis limited to the male population were an ABI < 0.85 (OR: 3.66; 95% CI: 1.04-12.84) and a personal history of coronary heart disease (OR: 3.34; 95% CI: 1.01-11.01). If male diabetics without either of these two factors are excluded, the negative predictive value for carotid stenosis is 96.6%. In conclusion, the prevalence of atherosclerotic carotid disease in diabetic patients is high. In these patients, the probability of finding >60% stenosis is highest among men with a history of coronary heart disease or an ABI <0.85.