by Dr. Richard L. Bruno
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 chronic fatigue tell me they do, too. Are these CFS 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 CFS or ME.
The President’s problem likely had to do with that pretzel overstimulating the vagus nerve, the main highway for nerve traffic to your esophagus — the swallowing tube — and to your stomach. The vagus carries commands from brain stem neurons to activate the muscles in your throat, esophagus and stomach that make swallowing possible. The vagus 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 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 chronic fatigue, 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 feel exhausted after eating meal. Food sticking in the esophagus or a full stomach apparently over stimulate the vagus nerve, trigger a drop in blood pressure and cause feelings of severe fatigue, even though these poliosurvivors don’t usually faint.
In 1995, pediatrician Peter Rowe found that some patients with CFS 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 parallels 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 CFS patient had “a purple discoloration” of her feet and hands after standing. This discoloration was reported in patients with chronic fatigue back in 1959 and is remarkably similar to polio survivors’ cold and purple “polio feet.” These findings indicate that both polio survivors and some chronic fatigue 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 Survey found that those with CFS or ME fainted nearly twice as often as they did before having chronic fatigue. 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 lifetimes 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 CFS and ME. So polio survivors and patients with chronic fatigue 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 chronic fatigue 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 and prevent fatigue or even a faint.
Dr. Richard Bruno is Director of Fatigue Management Programs and The Post-Polio Institute at Englewood (NJ) Hospital and Medical Center. His new book, THE POLIO PARADOX: UNCOVERING THE HIDDEN HISTORY OF POLIO TO UNDERSTAND TREAT “POST-POLIO SYNDROME” AND CHRONIC FATIGUE, will be published by Warner Books in June, 2002. E-mail questions to him at PolioParadox@aol.com
Bou-Holaigah I. Provocation of hypotension and pain during upright tilt table testing in adults with fibromyalgia. Clinical & Experimental Rheumatology, 1997; 15: 239-46.
Bruno RL. The Polio Paradox: Uncovering the Hidden History of Polio to Understand and Treat “Post-Polio Syndrome” and Chronic Fatigue. Warner Books, 2002, in press.
Bruno RL. Paralytic versus non-paralytic polio: A distinction without a difference? American Journal of Physical Medicine and
1999; 79: 4-12.
Bruno RL. Fainting and Fatigue: Causation or Coincidence? CFIDS Chronicle, 1996; 9(2): 37-39.
Bruno RL. Chronic fatigue, fainting and autonomic dysfunction: Further similarities between post-polio fatigue and Chronic Fatigue Syndrome? Journal of Chronic Fatigue Syndrome, 1997; 3: 107-117.
Bruno RL, Frick NM. Stress and “Type A” behavior as precipitants of Post-Polio Sequelae. In Research and Clinical Aspects of the Late Effects of Poliomyelitis. White Plains: March of Dimes Research Foundation, 1987.
Manyari D. Abnormal reflex venous function in patients with neurally mediated syncope J Am College Cardiology, 1996; 27: 1730-5.
Palmer E. The upper gastrointestinal vagovagal reflexes that affect the heart. Am J Gastroenterology, 1976; 66: 513-22.
Rowe P. Orthostatic intolerance and chronic fatigue syndrome associated with Ehlers-Danlos syndrome. J Pediatrics, 1999; 135: 494-9