Neuropathy in diabetes

Diabetic polyneuropathy is one of the commonest long-term complications of diabetes and the commonest form of neuropathy in the developed world. It encompasses a number of neuropathic syndromes, the commonest of which is chronic distal symmetrical polyneuropathy, also known as diabetic peripheral neuropathy (DPN). DPN is a cause of considerable morbidity, including foot ulceration, amputations and neuropathic pain, and is associated with cardiovascular disease and increased mortality. Risk factors for DPN include poor glucose control and markers of macrovascular disease, such as hypertension. There is now strong evidence implicating nerve ischaemia as the cause. Painful DPN affects 15–26% of all people with diabetes and can lead to considerable disability. The assessment and management of painful DPN continue to pose a considerable challenge. First-line therapies for painful DPN are tricyclic antidepressants (TCA), serotonin noradrenaline reuptake inhibitors (SNRIs), such as duloxetine, or anticonvulsants, such as pregabalin or gabapentin. Diabetic autonomic neuropathy results in considerable morbidity and reduction in quality of life, and is associated with increased mortality. It may involve cardiovascular, gastrointestinal, urogenital, pupillomotor, thermoregulatory and sudomotor function. Although some patients may be managed effectively by counselling and non-pharmacological interventions, the more severely afflicted patients will require pharmacological interventions.