The Effect of Peripheral Vascular Disease on Diabetic Neuropathy

Objective: To evaluate the effect of peripheral vascular disease (PVD) on diabetic neuropathy with the use of Doppler ultrasound and electrodiagnostic study. Method: One hundred fifty one patients with diabetes mellitus underwent nerve conduction studies. PVD was diagnosed when ankle-brachial index (ABI) was 0.9 and less and also toe-brachial index (TBI) was 0.7 and less. Electrophysiologically normal group was subdivided into nonPVD group (A1) and PVD group (A2). Diabetic neuropathy group was subdivided into non-PVD group (B1) and PVD group (B2). The frequency of diabetic neuropathy and the difference of amplitude, conduction velocity, and F wave latency within A groups and B groups were investigated. Results: Diabetic neuropathy was significantly correlated with PVD (p<0.05). There was no definite difference of electrophysiologic parameters between A1 and A2 groups. B1 group showed significantly reduced amplitude of sensory nerve action potential (SNAP) in sural nerve compared with B2 group (p<0.05). In all patients, the amplitude of SNAP in sural nerve was related with duration of diabetes and TBI by multiple linear regression analysis. Conclusion: This study supports the influence of PVD on diabetic neuropathy and suggests vascular abnormality in patients with diabetic neuropathy may result in predominantly axonal injury rather than demyelinating injury.