As a consumer health reporter, I assume I’ve heard of every health condition that affects at least half a million Americans, yet I’d never heard of postural orthostatic tachycardia syndrome or POTS until recently when a few family members and friends’ children were diagnosed with it.
The chronic condition causes dizziness, anxiety, nausea, heart palpitations, migraines, and a host of other miserable symptoms when sufferers stand upright. The half-million affected have it as a product of the body’s circulatory system adapting poorly, at times, to evolution.
“When humans stood upright, our system of blood vessels evolved to tighten and push blood upward to the heart and brain when we’re in a vertical position,” said Dr. Blair Grubb, a professor of medicine and pediatrics at the University of Toledo College of Medicine who has published research on POTS. “In those with POTS,” he added, “the system is malfunctioning and their blood vessels fail to tighten when they stand,” which causes their heart rate to surge — making some feel so sick that they climb back into bed.
“Their lives can be destroyed by POTS,” Grubb said, “and usually they can pinpoint the exact day they got sick.” Five times as many women suffer from the syndrome than men.
In a study published Monday in the British Medical Journal, researchers examined medical records and surveys from 136 patients diagnosed with POTS in Great Britain and found that the vast majority were young, well educated women who had “significant and debilitating symptoms” that impacted their quality of life. Previous US studies found that one in four of those diagnosed with the condition were disabled and could not attend work or school.
The British study also found that about one-quarter to one-third of those diagnosed with POTS weren’t on any medications for their condition.
“This was a surprise to me, how many patients in the studied were on no medications, but it suggests what we also see in this country, that the syndrome is under-treated and likely also under-diagnosed,” said Dr. Geoffrey Heyer, director of the POTS clinic at Nationwide Children’s Hospital in Columbus, Ohio.
POTS is often diagnosed using a tilt table test where patients lie prone on a table that’s tilted vertical – to mimic standing – while their heart-rate is monitored. Those with the condition experience a sudden increase in heart-rate of at least 30 beats per minute – or a pulse greater than 120 beats per minute -- when they stand upright.
Certain lifestyle therapies are frequently tried before prescription drugs. Patients are also told to drink about eight 8-ounce glasses of water each day and eat 2,000 to 4,000 milligrams of salt to increase the blood volume in their legs and help push blood upward. Wearing compression stockings can also help.
They’re also encouraged to exercise — quite a bit — to, in Grubb’s words, “enhance the effectiveness of the peripheral skeletal muscle pump” which pushes blood up from the legs and abdomen when they rise. He recommends at least 20 to 30 minutes a week of aerobic activity like walking, running, or biking and weight training for the legs, hips, and thighs.
While sitting or lying down for long periods during the day can alleviate POTS symptoms over the short term, it’s the worst thing patients can do, Heyer told me, because it causes a further deterioration of the body’s ability to regulate its blood vessels.
Drugs are prescribed largely on a trial and error basis, Heyer said. Blood pressure drugs called beta blockers can lower heart rate, which sometimes eases symptoms. “They work especially well in kids,” Heyer said. Another drug called fludrocortisone acetate (Florinef) can work to promote fluid retention and narrowing of blood vessels.
Beyond that, both Heyer and Grubb — who have long wait lists and see patients from all over the country — try a wide range of other medications including antidepressants and stimulants like Ritalin to see which works for which individual.
Part of the complexity in managing POTS lies in the fact that it has so many causes. Adults frequently find that their symptoms were preceded by a car accident, virus, head injury, or some other acute health problem that caused some kind of lingering disruption in their circulatory system.
For kids, the cause may be due to hormonal changes or a sudden growth spurt. “Teen girls often find that their symptoms get worse during their periods,” Grubb said. Growth spurts that move the head away from the body’s center of gravity in the chest could also trigger symptoms, he added.
The syndrome could also be caused by an autoimmune condition in which immune cells disrupt normal blood vessel functioning, according to a February study published in the Journal of the American Heart Association. While there’s no cure for POTS, Heyer said he sees some kids outgrow it in early adulthood and most find their symptoms wax and wane over time like other chronic conditions like asthma or back pain.
“Often exercise and learning good coping skills are key,” Heyer said, “to helping both teens and adults feel much better even if we can’t provide a cure.”