[7] Apart from renal function, cystatin C recently has been found associated with cardiovascular events.[8]–[10] And cystatin C was proved to be predictor for incidence of PAD events in elder people in the community [11] and cardiovascular mortality in PAD population. [12] However, there is limited data about the association between serum cystatin C levels and LLI in type 2 diabetic patients. This evidence concerns the gene CST3 and peripheral arterial disease.