Autonomic function in neuropathic diabetic patients with foot ulceration

Abstract

Objective: The aim of this study was to compare peripheral autonomic function in neuropathic diabetic subjects with and without foot ulceration.

Research design and methods: Measurements were made on 57 diabetic subjects; 35 subjects had evidence of peripheral neuropathy, 14 of these had a history of foot ulceration, and 22 subjects had no evidence of peripheral neuropathy. No patient had peripheral vascular disease. Measurements were made of motor and sensory nerve conduction. Autonomic function was investigated by using standard cardiovascular reflex tests and by measuring blood flow variability in the foot. The vasoconstrictor responses to deep breathing and body cooling were measured by using venous occlusion plethysmography.

Results: Peripheral sympathetic function was significantly worse in the DU group. The vasoconstrictor response to deep breathing in the DU group was significantly smaller than the response in the DN group (15.3 +/- 2.7 vs. 38 +/- 4%, P < 0.001). The response to body cooling in the DU group was significantly smaller than the response in the DN group (6.2 +/- 3.1 vs. 20.8 +/- 3.5%, P < 0.01). Tests of cardiac autonomic function and measurements of motor and sensory nerve conduction were similar in both neuropathic groups.

Conclusions: Peripheral autonomic neuropathy is associated with the development of foot ulceration in diabetic subjects.