Idiopathic neuropathy, prediabetes and the metabolic syndrome.

Peripheral neuropathy is a common problem encountered by neurologists and primary care physicians. While there are many causes for peripheral neuropathy, none can be identified in a large percentage of patients ("idiopathic neuropathy"). Despite its high prevalence, idiopathic neuropathy is poorly studied and understood. There is evolving evidence that impaired glucose tolerance (prediabetes) is associated with idiopathic neuropathy. Preliminary data from a multicenter study of diet and exercise in prediabetes (the Impaired Glucose Tolerance Neuropathy Study) suggests a diet and exercise counseling regimen based on the Diabetes Prevention Program results in improved metabolic measures and small fiber function. Prediabetes is part of the Metabolic Syndrome, which also includes hypertension, hyperlipidemia and obesity. Individual aspects of the Metabolic Syndrome influence risk and progression of diabetic neuropathy and may play a causative role in neuropathy both for those with prediabetes, and those with otherwise idiopathic neuropathy. Thus, a multifactorial treatment approach to individual components of Metabolic Syndrome may slow prediabetic neuropathy progression or result in improvement.