A Study On The Association Of Ankle-Brachial Index With Ischemic Stroke

Purpose: To explore the association of ankle-brachial index (ABI) with ischemic stroke.Object and Methods: 74 ischemic stroke patients were enrolled in this study, with 54 men and 20 women, age from 38 to 85 years old, the average age was 61.12±12.30 years. Patients were divided into large-artery atherosclerosis (LAA) group and small-artery occlusion (SAO) group according to TOAST typing. 26 persons without ischemic stroke who received healthy examination were enrolled into the control group, with 16 men and 10 women, age from 38 to 85 years old, the average age was 57.77±9.56 years. General clinical data of all the objects were recorded, including of age, sex, blood pressure, blood fat, et al. The extent and quantities of intracal artery stenosis were judged by Transcranial Doppler (TCD) and Magnetic Resonance Angiogram(MRA). Patients with Intracal artery stenosis or without were divided into two groups, non-stenosis group and stenosis group (including of 1-vessel stenosis group, 2-vessel stenosis group, 3-vessel stenosis group ). All the objects underwent ABI.Results: 1. Hypertensive disease, familial history of cardiac cerebrovascular disease and ABI abnormality were significantly different between ischemic stroke group and control group(P<0. 05). Age, sex, blood-fat abnormality, history of diabetes, cardiac disease,smoking and drinking were not significantly different between the ischemic stroke group and control group(P>0. 05). 2. The ratio of ABI abnormality was different between stenosis group and non-stenosis group(P<0.01); the value of ABI (0.88±0.16)in stenosis group was lower than non-stenosis group(1.04±0.07)(P<0.01). Compared with non-stenosis group, the ratio of ABI abnormality in 1-vessel stenosis group, 2-vessel stenosis group and 3-vessel stenosis group was significantly different(P<0. 05). The value of ABI in 3-vessel stenosis group was significantly different from non-stenosis group, 1-vessel stenosis group and 2-vessel stenosis group(P<0. 05), but the value of ABI in 1-vessel stenosis group was not significantly different from 2-vessel disease group(P>0. 05). 3. The ratio of ABI abnormality in ischemic stroke group was higher than control group(P<0.01). The value of ABI(0.94±0.15)in ischemic stroke group was lower than control group(1.03±0.09)(P<0.01). The ratio of ABI abnormality in LAA group was higher than SAO group(P<0.01). The value of ABI(0.88±0.16) in LAA group was lower than SAO group(1.03±0.06)and ischemic stroke group(1.03±0.09)( P<0.01), but was not different between SAO group and control group. The cutoff value of ABI≤0.8 had high sensitivity(75%)and specificity(98.2%)in predicting LAA.Conclusion: 1. ABI is associated with the quantity of intracal artery stenosis. 2. ABI is associated with ischemic stroke. Low ABI increases the risk of ischemic stroke. 3. ABI is associated with LAA but not SAO. ABI≤0.8 as a predictor for LAA has high sensitivity and specificity.