by Dr. Richard L. Bruno
The Massachusetts CFIDS/ME & FM Associaiton Spring 2002 UPDATE
While watching a football game President Bush swallowed a pretzel and fainted. They said it irritated his throat and made his blood pressure fall. I feel faint when food seems to get stuck behind my breastbone. I also get lightheaded and very tired after a big meal. Other people with the Chronic Fatigue and Immune Dysfunction Syndrome and fibromyalgia (CFIDS/FM) tell me they do, too. Are these CFIDS/FM symptoms?
President Bush swallows a pretzel that irritates his esophagus. The irritation causes his blood pressure to plummet and he faints. An unheard of experience? Not for some of the world's 20 million polio survivors and the estimated 10 million people with CFIDS/FM.
The President's problem likely had to do with the pretzel overstimulating the vagus nerve, the main highway for nerve traffic to your esophagus, your swallowing tube, and to your stomach. The vagus nerve carries commands from brain stem neurons to activate the muscles in your throat, esophagus and stomach that make swallowing possible. The vagus nerve also sends commands that tell your heart muscle to slow down and your blood vessels to open up. Vagus nerve stimulation, causing a drop in blood pressure due to blood vessels opening up, is responsible for the common faint, called vaso-vagal syncope.
But the vagus nerve is a two-way street: it both sends commands to your heart and gut and listens to the results of those commands. The vagus carries information about how much food is inside your throat, esophagus and stomach back to those same brain stem neurons. Anything that irritates the esophagus—like a pretzel getting stuck or even a full stomach— can stimulate the vagus nerve enough to drop blood pressure and cause a faint, which seems to be what happened to the President.
For Mr. Bush this is likely a one-time thing. But for polio survivors and people with CFIDS/FM, low blood pressure, lightheadedness and even fainting can be frequent occurrences. We know that the poliovirus damaged brain stem neurons that control the vagus nerve and possibly damaged the nerve itself. We have been following a growing number of post-polio patients who feel exhausted after eating meal. Food sticking in the esophagus or a full stomach apparently overstimulates the vagus nerve, triggers a drop in blood pressure and causes feelings of severe fatigue, even though these polio survivors don't usually faint.
In 1995, pediatrician Peter Rowe found that some patients with CFIDS also have fatigue that is associated with a drop in blood pressure when they stand up, take a hot shower or are in a hot room. Rowe's observations parallel the finding from our 1985 Post-Polio Survey that fatigue increased in more than one third of polio survivors when they were exposed to heat. Another parallel with polio survivors was Rowe's observation that a CFIDS patient had "a purple discoloration" of her feet and hands after standing. This discoloration was reported in patients with CFIDS back in 1959 and is remarkably similar to polio survivors' cold and purple "polio feet." These findings indicate that both polio survivors and some CFIDS/FM patients have lost the ability to regulate the size of their veins, which allows blood to pool, blood pressure to drop and causes feelings of fatigue.
Our 2001 International Chronic Fatigue Syndrome Survey found that those with CFIDS/FM fainted nearly twice as often as they did before having CFIDS/FM. Our 1995 International Post-Polio Survey found that polio survivors do not faint any more frequently than those who didn't have polio. But the 1995 Survey did find that anyone who had fainted even once in their lifetime reported significantly more severe daily fatigue than those who had never fainted. This suggests that damage to brain stem blood pressure control and vagus nerve neurons may be coupled to damage to brain activating neurons, the neurons that our and others' research suggests are responsible for symptoms of "brain fatigue" in polio survivors and those with CFIDS/FM. So polio survivors and patients with CFIDS/FM share abnormalities of blood vessels and blood pressure that seem to be related to brain stem neurons that are not functioning normally, probably as a result of virus damage to both brain activating and blood pressure control neurons.
What's to be done? Everyone with CFS should have their heart rate and blood pressure taken lying, sitting and standing. If fatigue is associated with a drop in blood pressure, compression stockings are often helpful to stop blood from pooling in the legs. If you need more help, go to a specialist in low blood pressure and ask about medications that increase the amount of fluid in your blood or reduce the size of your veins to stop blood from pooling in the legs. If fatigue is associated with meals, eating small bites and washing them down with liquid, as well as eating frequent, small, higher protein meals, can stop food from sticking in the esophagus and the stomach from getting too full, prevent over stimulating the vagus nerve and prevent fatigue or even a faint.
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Dr. Bruno is the Director of Fatigue Management Programs and The Post-Polio Institute at Englewood (NJ) Hospital and Medical Center. His book is The Polio Paradox: Uncovering The Hidden History of Polio to Understand and Treat "Post-Polio Syndrome" and Chronic Fatigue . See his website at www.postpolioinfo.com.