| POLIO TIPS AND TECHNIQUES
by Dr. Richard L. Bruno
If you’ve read our research, you know we’ve found evidence that a shortage of dopamine in neurons that activate the brain is related to polio survivors’ fatigue. Dopamine is the brain-activating neurochemical, but it also turns on the neurons that turn your muscles off when they’re not in use. Without enough dopamine, muscles turn on when they should be off, creating the rigidity and tremor of Parkinson’s disease.
So, why don’t all polio survivors have Parkinson’s? Horace Magoun, the researcher who discovered the brain-activating system, asked this question in 1948. Magoun concluded that if poliovirus-damage to dopamine neurons is severe, “some of the vital centers are destroyed and the patient does not survive.” That severe damage to the dopamine-producing neurons is accompanied by fatal brain damage is supported by the observation that nearly all of the few reported cases of polio in which Parkinson’s tremor and rigidity did appear were rapidly fatal.
Magoun also thought that if brain-activating system injury were less severe, damage would be “below the threshold necessary” for Parkinson’s symptoms to be seen, since 70% of dopamine neurons must be killed for tremor and rigidity to appear. So, our theory is that enough dopamine neurons were killed by the poliovirus to turn down the brain activating system, but not enough were killed to cause Parkinson’s disease. This is why, after studying and treating more than and 6,000 polio survivors, we have only seen a handful who have a “pill-rolling” tremor with hands at rest that is characteristic of Parkinson’s disease.
But, we have seen polio survivors with other kinds of shaking. Essential tremor, the most common cause of abnormal movements and second to stroke as the most common neurological disorder, is inherited and can affect the head, arms and hands. We’ve seen essential tremor in only a very few polio survivors. Intention tremor occurs only when a person moves and is what we see in polio survivors. It is caused by poliovirus-damaged motor neurons becoming tired with overuse. The tired motor neurons “stutter” when they send signals to make the muscles contract, which is seen as shaking in the muscles of the arm, hand, shoulder and legs.
In spite of the lack of a resting tremor, Post-Polio Sequelae and Parkinson’s disease are kissing cousins. Polio survivors and Parkinson’s patients both have fatigue and word-finding difficulty. In our 1990 Survey, more than three-quarters of polio survivors said that they had word-finding difficulty, with more than one-third reporting frequent, moderate to severe difficulty finding words. The greater polio survivors’ word finding difficulty, the greater their fatigue and the more difficulty they have focusing attention, a combination of symptoms that seem to be related to too little brain dopamine.
Would a drug that replaced dopamine in Parkinson’s patients reduce symptoms of post-polio fatigue. We studied bromocriptine, an anti-Parkinson’s drug, which directly stimulates dopamine receptors on brain activating system neurons. Five patients agreed to take a placebo and then increase doses of bromocriptine for a month as they rated their daily brain fatigue symptoms. Three noticed a reduction in fatigue symptoms on bromocriptine as compared to placebo, saying that they “felt awake” and “had a clear head” for the first time in years. The higher the dose of bromocriptine, the lower their daily difficulty with attention, word finding, mind wandering, concentration, memory and thinking clearly. Fatigue upon awakening decreased by just over 50%.
Is bromocriptine the treatment of choice for post-polio fatigue? Nope. The study’s most important finding was that almost 90% of the polio survivors we treated were not eligible for the drug trial since their daily fatigue was less than moderate after they had applied all of the symptom management techniques. The treatment of choice for brain fatigue—and for all PPS—is “The Golden Rule:” If anything causes fatigue, weakness or pain, don’t do it! (Or do much less of it.)
Dr. Richard Bruno is Director of The Post- Polio Institute at Englewood (NJ) Hospital.
