ANNOUNCER: Over 4 million Americans have diabetes. It is estimated that between 40 and 50 percent of these people will experience some form of nerve damage from their diabetes. Of this group, approximately one-third will develop a complication known as peripheral neuropathy.
RUSSELL K. PORTENOY, MD: The nervous system is divided into a central part, which consists of the brain and the spinal cord, and the peripheral part, which consists of all the nerves that travel into the body, including the extremities and the trunk and the internal organs.
ROY FREEMAN, MD: Peripheral neuropathy is the term that's used to describe damage, dysfunction, or even destruction of the nerves that go to the periphery of the body. So to the toes, the feet, the legs, the fingers, the hands, the arms, and sometimes the trunk, the chest, and even the head and the face.
ANNOUNCER: Nerve damage from diabetic peripheral neuropathy often cannot be reversed and can cause a variety of symptoms.
ASTRID ALMODOVAR, MD: In peripheral neuropathy we have, similar to schizophrenia, positive and negative symptoms. Positive symptoms would be burning, stinging, pins and needles. And, on the other side, the negative symptoms would be the absence of pain, anesthesia or paresthesia, when there is something there that should be felt.
ANNOUNCER: While peripheral neuropathy describes damage to any part of the peripheral nervous system, some patients with diabetes may also experience what's known as peripheral polyneuropathy. This is when many nerves of the peripheral nervous system do not work properly.
RUSSELL K. PORTENOY, MD: The earliest symptoms are typically numbness, tingling, or pain in the feet. Those symptoms can sometimes gradually ascend up the legs and ultimately move to involve both hands. The same kinds of symptoms, numbness, tingling and pain, will then affect the fingers, and can gradually travel up the hands and into the arms.
ANNOUNCER: The terms peripheral neuropathy and peripheral polyneuropathy are often used interchangeably, and diagnosis and treatment is the same for both.
There are many causes of peripheral neuropathy, including shingles, vitamin deficiencies, HIV, liver disease, and kidney disease, but diabetes is the leading cause in the United States.
Of the many symptoms associated with DPN, pain is the most distressing. The pain of DPN is potentially disabling and leads many patients to seek help.
ROY FREEMAN, MD: The pain can be present at rest and can be a burning sensation, a stabbing sensation, can be pins and needles that are uncomfortable, or it can be evoked by various stimuli. And some patients find it intolerable even to lie in bed; the contact merely with the bedclothes can be excruciatingly painful. Some patients find it difficult wearing shoes and socks, due to the discomfort of the peripheral neuropathy.
The pain is often worse at night, so patients very frequently don't get a good night's sleep and this leads to lack of concentration, irritability, mood change, depression, and a variety of other secondary consequences.
ANNOUNCER: In addition to pain, there are other signs and symptoms of DPN that can impact a person's life.
ROY FREEMAN, MD: There is the loss of sensation that can impair balance, result in the most simple of activities becoming impossible to perform. Loss of sensation patients are often unable to perceive coins in their pocket, unable to button up a shirt or tie a tie. Patients will have increased tendency to fall as a consequence of the peripheral neuropathy.
RUSSELL K. PORTENOY, MD: Foot ulcers may occur because the patient may not be aware that the skin has been damaged, and that may progress to a deep or non-healing ulcer and be quite a serious complication.
Occasionally, patients experience severe damage to the joints, again, for the same reason. The patient may not be aware that the joint has been injured, and they continue to walk on an injured joint until the damage progresses.
ROY FREEMAN, MD: In addition, there may be an increase in blood pressure or there may be the inability to change blood pressure when moving from a supine, or lying-down, to a standing-up position, so patients will feel dizzy, lightheaded and even faint.
ANNOUNCER: Perhaps one of the most devastating complications of DPN is the loss of sensation which can result in unnoticed injuries. If injuries go unnoticed, they may become infected and possibly gangrenous. In the most extreme cases, the infection can spread to the bone and require amputation.
RUSSELL K. PORTENOY, MD: Occasionally, patients with diabetic polyneuropathy, whether or not pain exists, can experience some very severe complications involving the lower extremities. One of these complications might be a severe infection that might start from the skin and then penetrate more deeply until it involves the bone. Osteomyelitis can result. That's the infection of the bone. And if that cannot be cured and progresses, sometimes it can get so severe that amputation is the only option. These are, fortunately, very uncommon and can partially be prevented by good diabetic control and meticulous foot care.
ANNOUNCER: Patients with diabetes should be aware of several risk factors for the development of peripheral neuropathy.
ROY FREEMAN, MD: The most important risk factor is an elevated blood sugar. In addition, age and duration of diabetes are two other important risk factors. Finally, it's becoming increasingly apparent that the cardiovascular risk factors may also play a role in the evolution of a diabetic peripheral neuropathy
ANNOUNCER: A diagnosis of DPN is based on many findings and should made by a health care professional.
RUSSELL K. PORTENOY, MD: When a patient with diabetes develops symptoms in the feet, like numbness, tingling or pain, and goes to a physician, that physician will first take a history, ask the patient about his or her symptoms, and then do an examination. The examination includes a neurological examination that specifically assesses how the nerves are functioning.
Once the physician makes that judgment, a variety of tests can be done to try to confirm that diagnosis. The physician will probably get some blood tests, both to determine how bad the diabetes is, and also to try to exclude other causes of polyneuropathy.
The physician might also send the patient to another doctor to get an electrical study, what are called nerve conduction studies. The purpose of the nerve conduction studies is to see how well the nerves in the legs and the arms conduct electricity and determine whether they're functioning normally or not. The combination of the history, the examination and the ancillary blood tests and electrical studies is enough to make the diagnosis of diabetic polyneuropathy.
ANNOUNCER: If a person with diabetes thinks they are experiencing peripheral neuropathy, there are several things they should do.
ROY FREEMAN, MD: Firstly, find a physician who understands diabetes and a diabetic peripheral neuropathy. Take control of your disease management by monitoring your diet, develop an exercise program and make sure that your blood glucose is as tightly controlled as possible.