Diabetic peripheral neuropathies: their cost to patient and society and the value of knowledge of risk factors for development of interventions.

Diabetic peripheral neuropathies are a variety of syndromes which affect sensory, autonomic and motor nerve function. The commonest form, distal symmetric sensory polyneuropathy, is a major risk factor for foot ulceration, which may eventually lead to lower limb amputation. By 2010, it is estimated that globally 220 million people will have diabetes, and epidemiological studies estimate that more than 50% of diabetic patients with a 25-year history will develop diabetic peripheral neuropathies. In 1986, the USA expenditure for care of these neuropathies was estimated at $240 million, and, as the incidence of diabetes is predicted to increase, this cost is likely to escalate. Risk factors associated with diabetic peripheral neuropathy need to be identified so that interventions can be devised. Recombinant nerve growth factor, a putative treatment for diabetic peripheral neuropathies, is currently being evaluated in phase III trials for this indication.