[The risk factors for abnormal ankle-brachial index in type 2 diabetic patients and clinical predictive value for diabetic foot].

OBJECTIVE: To investigate the prevalence of diabetic foot (DF) and the normal, high and low ankle brachial index (ABI) in type 2 diabetic patients and explore the risk factor for abnormal ABI and the clinical predictive value for DF. METHODS: A total of 2681 type 2 diabetic patients who visited our hospital between January, 2007 to December, 2009 were enrolled in the study. The clinical data were analyzed and the risk factors for abnormal ABI were determined by logistic regression analysis. RESULTS: ABI was normal (0.9-<1.3) in 2362 cases (88.1%), while below 0.9 in 277 cases (10.3%) and equal or over 1.3 in 42 cases (1.6%). The elderly patients ( ≥ 60 years) had a higher prevalence of low ABI than the non-elderly patients (20.41% vs. 4.10%, P < 0.01) . The prevalence of DF was 25.63%, 3.05%, 26.19% in ABI<0.9, 0.9-<1.3 and ≥ 1.3 groups, respectively, and the prevalence in groups ABI<0.9 and ≥ 1.3 was higher than that in group ABI 0.9-<1.3. Similar U-shape distribution was observed in the prevalence of abnormal ABI and DF. ABI was negatively correlated with age, diabetes duration, uric acid (UA), 24 hours microalbuminuria, while positively correlated with body mass index (BMI), diastolic blood pressure, triacylglyceride, total cholesterol and glycosylated hemoglobin A1c(HbA1c). Abnormal ABI was independently correlated with age, diabetes duration, HbA1c, UA, 24 hours microalbuminuria, diabetic kidney disease, diabetic retinopathy, diabetic peripheral neuropathy and diabetic vascular diseases. CONCLUSION: The prevalence of abnormal ABI is higher in the elderly patients with type 2 diabetes. Abnormal ABI could be an early predictor for DF.