Associated Analysis Of The Risk Factors For Peripheral Arterial Disease And The Clinical Diagnostic Research For Postexercise Ankle-brachial Index

ObjectiveTo explore the risk factors for peripheral arterial disease (PAD) and their correlations. And study the test threshold of postexercise ankle-brachial index (postexercise ABI) for PAD and evaluate its diagnostic value.Methods119 patients were enrolled. All the patients underwent computer technology angiography(CTA) of lower limbs, resting and postexercise ABI, history collection, blood biochemistry examination. PAD was diagnosed by CTA of lower limbs which showed the stenosis ratio equaled or more than 50% on either artery of the leg. The stenosis ratio less than 50% was non-PAD. According to the result of CTA, We divided them into two groups: PAD group and non-PAD group. We compared the differences of the risk factors between these two groups, and analyzed them by simple correlation and multiple stepwise regressions. Basing on the relation between the stenosis ratio of peripheral artery and ABI, we draw the receiver operator characteristic curve (ROC curve), and evaluate the diagnostic value of postexercise ABI.Results1. The comparison of clinic data between PAD group and non-PAD group: It was displayed that increase of age, high sensitive C reactive protein (Hs-CRP), hematocrit (HCT), fibrinogen (Fg), 2 hour plasma glucose(2hPG), glycosylated hemoglobin(HbAlc) values of PAD group were all significantly higher than those of non-PAD group (P<0.05), and decrese of adiponectin(APN) was lower than that of non-PAD group (P<0.05) .2. The simple correlation between PAD and the factors: There were positive correlation among PAD and age, Hs-CRP, HCT, Fg; and negative correlation between PAD and APN.3. The multiple stepwise regressions of the risk factors for peripheral arterial disease: HCT (standard regression coefficient Beta=0.441, P <0.05), age (standard regression coefficient Beta=0.357, P <0.05), Hs-CRP(standard regression coefficient Beta=0.534, P <0.05). They were the factors that influencing PAD.4. The ROC curve between resting and postexercise ABI: The area under curve (AUC) values for postexercise ABI was 0.988 (95% confidence interval 0.978~0.998,P=0.000), and that of resting ABI was 0.948 (95% confidence interval 0.920~0.970,P=0.000). The threshold value of ROC curve was the max between sensitivity and specificity. So the cutoff point on the ROC curve of postexercise ABI was 0.735.5. The evaluation for diagnostic value of postexercise ABI: The sensitivity of postexercise ABI was 91.4%, 95% confidence interval(91.339,91.461); the specificity was 94.9%, 95% confidence interval (94.857,94.943); the Youden's index was 0.863, 95% confidence interval(0.804,0.922); the positive likelihood ration was 17.920; and the negative likelihood ratio was 0.091.Conclusion1. There were positive correlation between PAD and risk factors. Except for the unchangeable factors as age, it was shown that the changes of the arteries had something to do with Hs-CRP, HCT, Fg, 2hPG, HbAlc and APN. And the changes of the arteries through the aspects of inflammation, blood clotting, hemorheology, glycometabolism and lipornetabolism which influenced the development of PAD. Age, Hs-CRP and HCT were the three factors that influencing the development of PAD. 2. The AUC value of postexercise ABI was larger than that of resting ABI. It meant that postexercise ABI was much more worth to screening the patients of PAD or non-PAD.