CST3 and triple-A syndrome: ROC curve analysis demonstrated the significant differences in human plasma total CatS, pro–CatS, and active CatS levels between AAA patients and controls (AUC [area under the ROC curve] = 0.76, P<0.001, AUC = 0.64, P<0.001, and AUC = 0.74, P<0.001, respectively), with optimal sensitivities and specificities of 0.70 and 0.70 versus 0.60 and 0.60 versus 0.69 and 0.69, respectively, but not plasma cystatin C level (AUC = 0.52, P = 0.534) (Figure 1).