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It's a nerve, not nervous, breakdown

Created date

August 12th, 2009

Imagine touching something and not being able to feel it. Now picture the other extreme nerves that often, sometimes constantly, feel as if they are on fire. These are just a few of the symptoms experienced by sufferers of peripheral neuropathy. Peripheral neuropathy affects 20 million Americans. (File photos) Peripheral neuropathy is a set of problems related to the peripheral nerves, the nerves that transmit signals from your spinal cord to and from your organs, limbs, fingers, toes, and other areas, like skin, says Audrey Penn, M.D., a neurologist and deputy director of the National Institute of Neurological Disorders and Stroke. Numerous causes Peripheral neuropathy isn t unusual. At least 20 million Americans suffer from one of the 100 different types. "It can develop for many reasons, but without a doubt the most common cause in seniors is diabetes," Penn says. About 60% to 70% of all people with diabetes have mild to severe forms of peripheral nerve damage. This condition is known specifically as "diabetic neuropathy." "Neuropathy can be a sign of diabetes that was not only undiagnosed but untreated for an average of five years," says Austin Welsh, M.D., physician at Erickson's Tallgrass Creek community in Overland Park, Kans. Besides diabetes, peripheral neuropathy s causes can include trauma to the nerve from an accident of some kind (including falls), viruses, and repetitive stress injuries (like carpal tunnel syndrome). It can develop from damage to the vascular system (controlling blood supply) limiting blood flow to the peripheral nerves. The latter is often related to diabetes. "It can also develop from decreased levels of vitamin B-12," Welsh says. Symptoms can be subtle While advanced stages of peripheral neuropathy can create severe problems, including trouble breathing and swallowing, initial symptoms are often very subtle. In fact, they are so subtle that many people see them as just part of getting old until the symptoms become truly annoying. "It can cause fainting from low blood pressure and bladder weakness. One of the problems seniors typically experience is loss of sensation in the feet. Neuropathy symptoms tend to be symmetrical; that is, they affect both sides. So if you re having problems in both hands or both legs, that often indicates neuropathy," Penn says. In many neuropathies, a substance called "myelin" is being destroyed. Myelin is a protective coating that allows sensations to travel along the nerves; the less you have, the longer it takes for those signals to travel, and ultimately they may not travel at all. This contributes to weakness in neuropathies. Your outer limbs may feel encased in gloves or stockings even when they re bare. This can lead to difficulty with balance or buttoning clothes. "Trouble grasping things is common," Penn says. "If you re having trouble walking or feel clumsy, it s time for a checkup," she adds. The diagnosis "If I see unusual cuts on the hands or feet, or if people tell me those areas are tingling or numb, I worry about neuropathy. If there are recurrent falls, I make a neuropathy check part of the workup," Welsh says. That check includes testing someone s blood sugar levels and A1C level (a test for diabetes). "To truly diagnose neuropathy and its level, you should have a specialist do a complete neurological workup. That specialist would be a neurologist or a physiatrist," Penn says. Physiatrists are experts in diagnosing and treating pain. One simple test the doctor might conduct is to ask you to try to make a fist. The doctor might also grasp your big toe on either side and move it up and down while your eyes are closed to see if you can feel the movement. "Also with your eyes closed, the doctor may check whether you can feel a cotton swab as it touches different parts of your skin. How about feeling pinpricks?" Penn says. A more sophisticated test, and one of the most common for peripheral neuropathy, is electromyography (EMG). A fine needle is inserted into a muscle to measure the amount of electrical activity present when muscles are at rest and when they contract. EMG tests can help differentiate between muscle and nerve disorders. Fighting advancement "Usually neuropathy does not resolve, but if the cause is controlled, its advance may be stopped," Welsh says. "For example, if it s developing due to carpal tunnel syndrome, there s a surgery to release the nerve causing it." Supplementing B-12 in someone s diet, perhaps through B-12 shots, may help. For mild pain, over-the-counter medicines like aspirin and ibuprofen may work too. "Medications can t cure the disorder, but some can be helpful in fighting the irritating sensations. A standard treatment is gabapentin (Neurontin). Newer (and more expensive) drugs include Lyrica and Cymbalta, an antidepressant," he says. Since diabetes is a major factor, preventing it is key to preventing neuropathy. If diabetes is already present, then controlling it using the same methods used to control other diabetes-related problems like heart disease and high blood pressure is critical. Talk to your doctor about the next steps you should take toward weight loss, good dietary changes, exercise, and other healthy lifestyle changes.