MedifocusHealth

Diabetes (type I and type II) is the most common cause of peripheral neuropathy (PN) in Western countries. The cause of diabetic neuropathy is not completely understood but some researchers theorize that the metabolic consequences of insulin deficiency and hyperglycemia are related to the initial damage of the nerve fibers and vascular insufficiency, which is common in diabetes, and may accelerate the neuropathic injury.

Peripheral neuropathy is one of the most common long-term complications of diabetes. Estimates of incidence vary widely and range from approximately 10% of diabetic patients to close to 90%. It occurs equally among Type I and Type II diabetics and has more of an effect on the quality of life of diabetic patients than other aspects of the condition (e.g. dietary restriction). The number of people affected by diabetic neuropathy increases with age since it can develop several years after the onset of diabetes. It is important to distinguish the origin of the symptoms of peripheral neuropathy in the diabetic patient since up to 10% of diabetics may have signs of peripheral neuropathy from nondiabetic causes. Progression of diabetic neuropathy is thought to be closely related to controlling the level of glucose in the blood (glycemic control).

Diabetic neuropathy accounts for more diabetes related hospitalizations than any other complication. The greatest danger associated with diabetic neuropathy is foot ulceration which can lead to the onset of gangrene and may require subsequent amputation. The presence of neuropathy significantly increases the risk of amputation. By some estimates, diabetic neuropathy is responsible for up to 75% of non-trauma related amputations among diabetics.

Diabetic neuropathy is associated with Type I and Type II diabetes although the progression is different. In Type I diabetes, typically there is a rapid deterioration of nerve function soon after onset and then it slows down, whereas, in Type II diabetes, the nerve damage and symptoms of neuropathy are present at diagnosis and progress thereafter at a steady rate.

Diabetic neuropathy can occur in the somatic or autonomic parts of the peripheral nervous system. Nearly 50% of diabetic patients may have symptoms of autonomic peripheral neuropathy which can be mild but, nevertheless, potentially life threatening. Symptoms associated with cardiac disease, (e.g., silent cardiac ischemia, orthostatic hypotension) can be fatal or can cause significant morbidity. Cardiac disease accounts for up to 25% of deaths of diabetic patients over a 10 year time period from the time of diagnosis and is an independent risk factor for stroke.

Types of Diabetic Neuropathy

• Focal neuropathy - This occurs in older adults with diabetes and is usually characterized by intense acute pain which resolves within 6-8 weeks. This category includes mononeuropathy, radiculopathy, and entrapment syndromes (e.g. carpal tunnel syndrome) which occur approximately three times as often in the diabetic population.

• Distal symmetric polyneuropathy - This is the most commonly recognized form of diabetic neuropathy. It can involve small and/or large fibers and often commences with the beginning of insulin therapy for diabetes or with stress. It may manifest as sensory or motor neuropathy. Small nerve fiber dysfunction often occurs quite early in diabetes with symptoms of pain and exaggerated reactivity to touch (hyperalgesia).