Some clinical factors contributing to the development of the diabetic foot.

Clinical neurological studies, blood pressure measurements and some haematological investigations were performed on a random sample of forty-four patients, at the Diabetes Out-Patient Clinic of the University Hospital of the West Indies (UHWI), to examine some of the factors that predispose to the development of the diabetic foot. Our results revealed that 86% of the patients had elevated glycosylated haemoglobin (HbA1 > 9.0%), 82% had clinical signs of peripheral sensory neuropathy, 29% had signs of autonomic neuropathy in addition to peripheral sensory neuropathy. Sixty-one per cent (61%) of the patients had ankle/arm systolic blood pressure ratio less than 1.0 and were diagnosed as having peripheral vascular disease (PVD). The group with neuropathy was found to have a significantly lower diastolic blood pressure (p < 0.0005) than the group without neuropathy. We believe that hyperglycaemia-induced vasodilation (indicated by a lower diastolic blood pressure) in a significant number of diabetics resulted in compensatory shunting of blood from the deeper tissues, including nerves, to the periphery. The resulting endoneural hypoxia could be responsible for the unusually high incidence of peripheral sensory neuropathy detected in this sample of diabetic patients. Metabolic factors may also play a role.