[Clinical aspects, diagnosis and therapy of diabetic neuropathy]

Diabetic neuropathy is regarded as the most common form of neuropathy in the Western industrial countries. At least one third of the diabetic patients is affected by a clinically manifest peripheral neuropathy, which can be diagnosed by the clinical neurological examination without a great deal of effort. The involvement of the autonomic nervous system may be associated with an increased mortality. It may result in erectile impotence as well as severe physical disability from orthostatic hypotension, fecal incontinence or bladder dysfunction and life-threatening complications such as silent myocardial infarction or sudden death. Diabetic cardiovascular autonomic neuropathy is detected in more than 20% of the patients. The best possible glycaemic control including patient education is regarded as the most important therapeutic measure. However, additional drug treatment is frequently needed to maintain the patient's quality of life. It is usually effective in reducing symptoms of diabetic peripheral neuropathy. The therapeutic prospects depend not only on the treatment approach but also on the stage of the neuropathic process. Favourable effects can be expected particularly in terms of prevention and in the early stages of the disease. Treatment options based on the current pathogenetic concepts are restricted to clinical trials, except for the antioxidant mode of action. The efficacy of symptomatic treatment is limited for some drugs, and significant adverse reactions are common. Therefore, before any symptomatic drug treatment is initiated, its potential risk should be thoroughly weighed against its possible benefit.