by John A. Senneff 

Symptoms and Effects
     Symptoms of sensory neuropathies, which may gradually occur over many months, often include numbness of the affected members, burning, tingling sensations, "electric" shocks, aching pain and extreme sensitivity to touch.
     Motor neuropathies frequently result in weakness in the feet, ankles, hands and wrists. Diarrhea, light-headedness or sexual dysfunction are some of the possible consequences of autonomic neuropathies. In severe cases involving these neuropathies, activities such as walking normally and sleeping may be nearly impossible.
     In rare situations even respiratory failure or paralysis may occur with certain neuropathies such as Guillain-Barre syndrome.

Causes
     There are said to be more than 100 causes of peripheral neuropathy. Diabetes is considered the most common, at least in the United States. It is variously estimated that 30 to 65% of people with diabetes have PN to some degree. In this group it is especially prevalent among those having particular difficulty in controlling their blood glucose levels and/or those having high lipid levels (cholesterol and triglycerides), those over 40 and among smokers.
     PN also is said to cause pain for up to one third of people with AIDS or HIV. In fact it is thought to be the most frequent neurologic disorder associated with HIV infection, typically occurring in the later stages of the disease.
     Various toxins and metallic poisons (such as arsenic, lead and mercury), certain chemicals (especially solvents and some insecticides), excessive alcohol intake, vitamin deficiencies (particularly B12) or vitamin excesses (B6), nutritional imbalances, and a number of drugs used to treat HIV infections and AIDS can all cause peripheral neuropathy. It can also result from kidney failure, liver disease, rheumatoid arthritis, abnormal blood proteins, cancer (and even cancer chemotherapy), leukemia and shingles.
     Certain repetitive activities such as typing can also be the cause of some neuropathies. Carpal tunnel syndrome is one example. This is a so-called entrapment neuropathy— a condition resulting from a nerve lesion at a point where the nerve is confined to a narrow passageway. Another instance of entrapment neuropathy is where restrictive clothing compresses a nerve called the lateral femoral cutaneous nerve which runs from the groin to the upper thigh.
     A tendency toward peripheral neuropathy can also be inherited. A family history of the disorder increases the likelihood. In a different twist on inherited susceptibility, a study done in France in 1995, reported in the November 1995 issue of Alcohol and Alcoholism, suggested a relationship between a history of alcoholism in a father and peripheral neuropathy in his alcoholic offspring. Ninety alcoholics, some with neuropathies and some without, were included in the study. The investigators found neuropathies occurred in alcoholics five times as often when the father was an alcoholic himself than when he was not. (Unfortunately, the study did not consider the incidence of PN in the alcoholic fathers, raising the obvious question whether perhaps it was the PN itself which was inherited rather than a greater disposition to neuropathy simply because of The publication Bio Medical Frontiers reports that the cause of one third of all neuropathies is unknown— mine included. These cryptogenic disorders are called "idiopathic." Some clinicians believe many of these unexplained cases are really genetic in origin.
     Incidentally, I discovered that not only does my neuropathy have a name— idiopathic— it has a number. Under the International Classification of Diseases- a world-wide system which groups related diseases and procedures for reporting statistical information— idiopathic neuropathy is code 356.8. A word of advice: if you happen to be idiopathic and are ever doing a slow shuffle down the street, having a particularly bad day with your PN, and somebody annoyingly asks what's wrong with you, you can be sure they won't stay around too long if you say "I've got the 356.8 disease."

Coping with Peripheral Neuropathy
It may not be possible for us to feel like we once did before we got stuck with this atrocious ailment— at least not yet, not until some true cure comes along— but there is much we can do now to improve the quality of our lives.

Benefits of Exercise
     Most clinicians think the benefits of exercise stem largely from the improvement in blood circulation it produces. This improvement permits oxygen to be carried to various parts of the body (including nerve tissue) where it's needed most. Also a good exercise program will almost inevitably lead to a loss of weight— a desirable goal in itself for most people and one which is believed especially important for people with neuropathy. In any event, as one PNer said plaintively : "At least one good thing about weight reduction is there is less of you to hurt."
     Of course beyond any particular PN benefits, there are a number of general health boons from exercise. These include the reduction of low density lipids (LDLs) and triglycerides, the increase of favored high density lipids (HDLs), and the lowering of blood pressure. David C. Nieman, professor of health and exercise science at Appalachian State University in Boone, North Carolina, also points out that moderate daily exercise can boost the body's immune system.
     I found one formal study on the value of exercise to PNers. As reported in the October 1997 issue of Physical Therapy, 28 subjects with peripheral neuropathy between the ages of 23 to 84 were followed through a six week period during which half completed a home exercise program. Dr. Richard K. Shields, a professor in the Physical Therapy Graduate Program at the College of Medicine, University of Iowa, was the principal investigator in the study.
     Subjects were given stretching bands to exercise the upper body, gradually increasing resistance, with a goal of 10 daily repetitions. They also were instructed to exercise aerobically up to 20 minutes each day, either by walking or bicycling, with enough intensity to achieve a heart rate of 60 to 70% of their estimated maximum heart rate (220 minus their age).
     Study conclusions were based on impairment measures which included average muscle scores, handgrip force, walking time and "forced vital capacity." A health survey was also used which dealt with quality of life perceptions.
     At the end of the six week period those in the exercise group showed moderate improvements in their strength impairment measures, as could be expected. What was noteworthy were the significant improvements reported in the quality of life surveys. Exercise participants indicated on average a meaningful change in "physical and mental role limitations" (self perceptions of physical and mental disabilities) and "social function limitations" (self perceptions of interference with normal social activities). The study did not, however, demonstrate any overall pain reduction for those participants. From an analysis of the results Dr. Shields concluded that a home exercise program should be an important component of treating people with peripheral neuropathy.
     I think the message from this study is that, apart from any direct physical benefits (which can be significant), exercise makes us feel better about ourselves, that perhaps we figure we are not quite as hobbled by our PN as we previously thought, that we look better, have more energy, are generally healthier and happier, etc.

Types of Exercise
     Of the various forms of exercise, most PNers seem to agree water aerobics (such as running in deep water while wearing flotation devices) or simply swimming laps, or a combination of the two, is best since it takes the weight off of painful feet while you're exercising. Also it's easier to stretch and work muscles in the water. If you prefer to exercise in the shallower end of a pool you might consider buying a pair of water shoes to give your feet some protection and traction. (Occasionally people simply use old tennis shoes for this purpose.) To get the full benefit of any water workout it's suggested you spend at least 30 minutes in a pool, daily if possible but at least several times a week.
     If our feet can handle walking— the faster the better— that also is an excellent form of exercise. Unfortunately running or jogging must remain a memory for most of us who used to enjoy those pursuits. A treadmill provides much the same walking experience but under controlled conditions. (I used to have one but my feet couldn't take it anymore.)
     The Stair Master is a step removed (no pun intended) from walking. This machine eliminates the foot impact of walking— though it can still put stress on your feet as you push down. I personally prefer a machine called the Precor, where you slide your legs back and forth in a gliding motion while your feet are planted on "skis." With the Precor you can increase the resistance or raise or lower the height of the ski tips on the control panel. Another so-called elliptical machine is the Body Trek which involves the use of arms as well as legs.
     Easier on the feet yet are exercise bikes. A type many favor, me included, are recumbent models where you plop yourself in a "chair" and pedal while sitting back with your legs pumping horizontally. You can read, watch TV or just listen to music, all while getting a great workout.
     Many PNers also use strength-building routines such as weight lifting. Well equipped fitness centers offer all kinds of equipment for this purpose.
     Physical therapy experts maintain that gradual stretching and strengthening exercises help relieve the stress of chronic pain. An organization called Stretching, Inc., has a web site (www.stretching.com) offering various helpful books on stretching and body building techniques. Incidentally it is always a good idea to have a trained physical therapist formulate your exercise program.
     One other form of exercise some PNers use is the Chinese martial arts routine called tai chi. This is a training exercise involving slow, graceful movements such as seen performed in Chinese parks early in the morning. These movements are derived from the movements of animals and follow a natural, relaxed pattern. They increase the body's motion range and are said to exercise the internal organs. (Don't ask me how.) According to practitioners the slow meditative routine aids relaxation, stress reduction, balance and posture, and increases blood flow.
     Diabetic PNers are again reminded to check with their physicians prior to engaging in exercise programs.

From Numb Toes and Aching Soles: Coping with Peripheral Neuropathy, by John A. Senneff. Copyright © 1999 by John A. Senneff. Excerpted by arrangement with John A. Senneff. $19.95. Available in local bookstores or call toll free 888-633-9898 or click here.