Diabetic state as a crucial factor for impaired arterial elastic properties in patients with peripheral arterial disease

Background Increased arterial stiffness is associated with greater risk of cardiovascular events and mortality. However, in patients with peripheral arterial disease (PAD) who have severe atherosclerotic disorder or risk clustering, the major determinants of increased stiffness have been not clarified. Methods This study investigated the associations between elastic properties of the carotid artery as measured by ultrasonography and atherosclerotic risk factors, with particular focus on diabetes mellitus (DM), in PAD patients ( n =481; mean age, 69.6 years). DM was defined as hemoglobin A1c ≥6.5%, administration of anti-diabetic agents, or DM pattern on 75-g oral glucose tolerance test. Stiffness β index was calculated from luminal diameter changes measured by the M-mode method using a linear array imaging probe. Results Stiffness parameter β was significantly increased in diabetic patients compared with non-diabetic patients (9.56±0.35 vs. 8.31±0.32; p =0.009) in an age- and gender-adjusted model. This significant difference was maintained in a multivariate-adjusted model including age, gender, hypertension, hyperlipidemia, obesity and smoking history (9.43±0.36 vs. 8.39±0.33; p =0.037). No significant differences in mean intima-media complex thickness or plaque score of the carotid artery were seen between diabetic and non-diabetic patients. Conclusion Diabetic condition impairs the elastic properties of arteries, independent of other known atherosclerotic risk factors or excessive intimal diseases in PAD patients. This may support the notion that diabetic condition can worsen prognosis for PAD patients.