Until long-haul COVID emerged during the COVID-19 pandemic, postural orthostatic tachycardia syndrome (POTS) was seen as a challenging, backwater diagnosis and a strange bedfellow of another vague, outsider medical condition, chronic fatigue.
Now, Mayo Clinic’s Philip R. Fischer, M.D. — a leading pediatric chronic fatigue and POTS expert for two decades — has been thrust center stage as science seeks to understand long-haul COVID. Specifically, there is great interest in how long-haul COVID is similar to — or different from — POTS and chronic fatigue, which are scientifically better understood.
Timed perfectly with the surge of interest in these diseases, Dr. Fischer has just published a definitive new book. “Tired Teens: Understanding and Conquering Chronic Fatigue and POTS” is a thorough but easy-to-grasp guide to understanding fatigue in children — and when to suspect your child may be experiencing fatigue that has an underlying medical cause.
What is chronic fatigue?
We’ve all experienced periods of tiredness, the kind that makes everyday tasks feel depleting and overwhelming and gets us worrying that something‘s not quite right. We can spot this in our children too. A trip to the doctor and some tests may reveal that your child does indeed have an underlying cause of fatigue, such as mild anemia that can be treated by iron supplements, or a diagnosis of major depressive disorder.
Chronic fatigue, on the other hand, is a medical condition sometimes triggered by viral infections, immune system problems, hormonal imbalances, or physical and emotional trauma. Most of the time, the cause is not known. It is diagnosed when:
- There is a persistent, debilitating fatigue that lasts longer than six months
- It worsens with physical or mental activity but crucially doesn’t improve with rest
- No other underlying medical explanation can be found during extensive tests
Typical symptoms include:
- Sore throat
- Problems with memory and concentration
- Unrefreshing sleep
- Dizziness on sitting or standing up (known as orthostatic intolerance)
- Enlarged lymph nodes and muscle or joint pain
Chronic fatigue can only be diagnosed after a long list of conditions have been ruled out. These conditions include iron deficiency, insufficient quality sleep or sleep disorders, depression, anxiety, thyroid disorders, diabetes, low blood sugar (hypoglycemia), adrenal disorders, liver or kidney conditions, and digestive disorders, especially celiac disease and inflammatory bowel disease. Due to this process of elimination, the journey to a diagnosis can take as long as a year.
And what is POTS?
The symptoms of POTS are very similar to chronic fatigue, but are distinguished by acute dizziness on sitting up from lying down or on standing up. In “Tired Teens,” Fischer explains that the condition typically develops following an illness or injury, “POTS is a condition of bothersome symptoms — dizziness with postural changes, fatigue lots of the time — that add up to make a syndrome.”
As Fischer explains: “When a person with POTS stands up, the autonomic nervous system isn’t doing a good job of telling blood vessels in the legs to tighten up and send blood flowing back to the heart. Instead the vessels stay floppy and the blood pools in the legs. As a result the heart tries to make up for inadequate blood flow by pumping faster, increasing the heart rate.”
Other symptoms may include:
- Abdominal pain
- Chest pain
- Brain fog
- Blue feet
Dr. Fischer says that POTS tends to target high achievers — think of the straight A student, violin prodigy, swim team star — who burn the candle at both ends. This person often catches a powerful seasonal virus and suddenly finds that putting on her swimwear leaves her breathless and standing up sends the room spinning. Notably, a majority of adolescents with POTS are female.
Diagnosing POTS requires an exhaustive process of investigative elimination, with overlap with many standard tests carried out for chronic fatigue, plus a range of conditions that also cause an excessive heart rate on standing, also needing to be ruled out:
- Dehydration and blood loss
- Autonomic function tests
- Heart and lung irregularities
- Heart rhythm conditions
- Anxiety and pain
Unfortunately, Fischer says, many primary care physicians do not refer for these additional tests.
“If doctors don’t see it on a lab result it’s not there,” he says. “The lab results look normal, the x-ray looks normal, so they tell the patient ‘Everything is normal.’ Not all diseases are diagnosable by a test. And part of the trouble with POTS is it’s not a structural body problem. It’s a nervous system regulation and coordination problem.”
Dr. Fischer continues: “There are three parts of what the autonomic involuntary nervous system does: blood flow, intestinal flow and temperature regulation. So if my patient is dizzy and tired from her blood not going to the right places at the right time and has nausea and tummy aches from the intestines not moving right — and if my patient feels too hot or too cold — that’s three of three of the involuntary nervous system not working.”
Once all tests have led nowhere and symptoms have been present for a minimum of three months, Dr. Fischer will order a “tilt test.” This involves laying on a table, and being cinched in place by secure straps. Once the resting pulse is stable, the table is tilted at a 70-degree angle and the pulse assessed over 5 to 10 minutes. The difference between the lying down (supine) pulse and the standing heart rate is then contrasted. If a pulse change of 40 or more beats per minute for a teenager is met (the medical threshold for diagnosis), then POTS is confirmed. (By contrast, in adults, the pulse change is diagnosed at 30 beats or more per minute.)
How are chronic fatigue and POTS treated?
Fischer treats teens with a plan he developed called the STEPS program. It’s based on the premise that countering the extreme fatigue with intentional movement and action is the best treatment available. The STEPS program focuses on:
- Increase Salt intake
- Take lots of fluids
- More Exercise
- Take medications such as beta blockers or antidepressants Prescribed by your doctor
- Go to School, get plenty of Sleep, get psychological and physical Support
Enter long COVID
If your child caught COVID-19 and went on to develop symptoms of long COVID, then you’ll be all too familiar with the knock-out exhaustion that defines this globally trending, post-viral malaise. Long COVID has a wide range of symptoms, most of which overlap with symptoms of chronic fatigue and POTS:
- Brain fog
- Heart palpitations
- Loss of smell or taste
- Muscular aches
- Chest tightness
- Ringing in ears (tinnitus)
- Loss of appetite
What chronic fatigue and POTS can teach us about long COVID
“Those of us dealing with chronic fatigue that’s often post viral were ready for long COVID,” says Dr. Fischer. “In the past we would see chronic fatigue and dizziness in teenagers after they got the Epstein-Barr virus — the most common virus that causes mono — or after there was a really bad flu season. When there’s a really bad regular illness we see more chronic fatigue after it. So a lot of the fatigue related to a COVID infection fits this pattern.”
Fischer is currently seeing many children with long COVID and chronic fatigue and feels very seasoned with how to tackle it.
“Everything we’ve learned from our patients with chronic fatigue and POTS over the past 20 years makes long COVID make a lot more sense. A lot of people who have long COVID have autonomic nervous system dysfunction. They might not have the actual fast heart rate that is typical of POTS. But it’s the same sort of condition and the treatment is the same.”
In late 2019 and early 2020, Fischer could see doctors struggle with how to approach long COVID.
“Part of the mystery of long COVID initially,” he says, “was that people were looking for what part of the body was going wrong. But sometimes, as with POTS, it’s the nervous system that is not regulating the different parts adequately.”
Despite such understanding, long COVID has made Fischer’s diagnostic task that bit harder.
“Where do I put long COVID in the consideration of chronic fatigue?” he says. “I hear the patient’s whole story and if they’ve had COVID-19, I’ll make sure there is no remaining heart or lung disease that’s accounting for the symptoms — and that there’s no other active treatable disease, whether it’s iron deficiency, celiac disease or thyroid problems. Once we know we’re not missing any of that — or we’re treating that and there’s still trouble — then we have to suspect it’s an involuntary autonomic nervous system problem and then we’ll deal with that. But in the end, it’s the same diagnostic process I have used for chronic fatigue and POTS for 20 years, in terms of piecing it all together.”
How treatment for long COVID mirrors that of chronic fatigue and POTS
- If you feel too tired to do things from long COVID and you just sit around, you will get worse
- If you make yourself increase exercise, activity, get good sleep and eat well, you will slowly see improvements
- If you feel dizzy, drink a lot of fluid and eat a lot of salt
If people do these things, which are the opposite of what their body’s telling them to do, then they’re going to get better whether it was COVID behind their symptoms or not.
Looking to the future
In “Tired Teens,” Dr. Fischer writes of how long it took many of his medical peers to take chronic fatigue and POTS seriously or even know what each was. Now, with medical journals around the world citing chronic fatigue and POTS in long COVID discussions, Dr. Fischer is excited by where this may lead.
“COVID-19 is a terrible virus but one of the good things — if we can say anything about it that is good — is that the delay in diagnosing POTS is going to shrink because people are going to realize that long COVID could be causing POTS and it will lead to more doctors thinking earlier about the involuntary nervous system. Both are going to be more easily diagnosed than before because of greater awareness.
“It looks like COVID-19 is going to end up destigmatizing chronic fatigue and POTS and getting a whole lot of people better at the same time and faster than ever. Who would have even thought this could happen?”