Postural Orthostatic Tachycardia Syndrome

Mysterious Symptoms

Dizziness is one of the main symptoms of POTS.
Teens with POTS typical have daily symptoms that can interfere with their daily activities. Photo by Patrick Sheandell/Getty Images

You have probably never heard of postural orthostatic tachycardia syndrome or POTS, even though it affects many people, including teens, and was identified in the early 1990s. The National Dysautonomia Research Foundation describes children with these disorders as invisible to outsiders, who may think that they are faking their symptoms.

That it isn't more well known can be even more frustrating because POTS can cause such debilitating symptoms, including dizziness, headaches, and fatigue, etc.

Postural Orthostatic Tachycardia Syndrome

Postural orthostatic tachycardia syndrome (POTS) is caused by alterations or dysfunction in the autonomic nervous system (dysautonomia).

In addition to the central nervous system (our brain and spinal cord), we have an autonomic nervous system that helps to involuntarily control many things our body does, such as:

  • dilating our pupils when we go into a dark room
  • increasing saliva production when we eat
  • causing us to sweat when we get hot

The autonomic nervous system also helps regulate our heart rate and blood pressure. That is especially important when we change position, like going from supine (lying down) or sitting to a standing position.

When we stand up, many things happen in our bodies that we don't notice, or at least we don't notice when they happen correctly. In response to a large amount of blood moving to our lower body, which initially drops our blood pressure, the autonomic nervous system increases our heart rate, constricts or tightens blood vessels and increases our blood pressure, all to maintain blood flow to our brain.

Muscles in our legs and abdomen also compress veins in these parts of our body and help with the process.

POTS is thought to occur when this system doesn't work properly, causing affected people to get dizzy when they stand, among other symptoms.

It is most common in women, especially women between the ages of 15 and 50 years of age (menarche to menopause).

Although it is not known what causes POTS, it does often begin after a prolonged viral illness, like the flu or mono.

Symptoms of Postural Orthostatic Tachycardia Syndrome

The classic definition of POTS in teenagers is feeling lightheaded and having a heart rate that rises more than 40 beats per minute (or a heart rate above 120 beats per minute), within 10 minutes of standing up.​

In addition to often feeling dizzy, other symptoms of POTS can include:

  • headaches
  • weakness, fatigue, and exercise intolerance
  • nausea and abdominal discomfort
  • tachycardia (fast heart rate) and palpitations
  • near syncope - feeling like you are going to faint
  • burred vision
  • anxiety
  • sweating inappropriately
  • trouble sleeping
  • difficulty concentrating

In addition to having classic symptoms, tilt-table testing can be done to help diagnose teens with POTS. A tilt test can also be done after a teen has been supine for 5 minutes, measuring her heart rate and blood pressure, and then after she has been standing for 3, 5, 7, and 10 minutes.

Dizziness and Fainting vs. POTS

Dizziness and even fainting (syncope) are actually common symptoms in teens.

In fact, it is thought that up to 15% of teens will faint at least once before they reach adulthood, usually around the age of 15 years. Fortunately, most of these teens with dizziness and fainting won't have POTS. Instead, they will have more common disorders, such as:

  • vasovagal syncope - also called postural syncope, it can be caused when you are standing for too long in one place (blood pools in your arms and legs, especially if you aren't moving them much) or in response to pain or fear.
  • transient orthostatic intolerance - can occur when you are sick with the flu or a stomach virus, etc., causing you to be a little dehydrated and get dizzy when you stand up
  • orthostatic hypotension - like POTS, occurs when you stand up

The big difference between these conditions and POTS is that, unlike POTS, these symptoms likely won't be daily and they shouldn't be debilitating.

In addition to treating any underlying dehydration, the best treatments for these causes of syncope are usually countermeasures to help prevent them from occurring. At the first sign that your teen feels like she might faint, it is usually recommended that he or she sit, squat, or lie down. These teens should also make sure that they get enough salt and water in their diets.

Treatments for Postural Orthostatic Tachycardia Syndrome

Since POTS can be so debilitating, finding effective treatments are important, including:

  • elevating the head of your child's bed by 4-6 inches.
  • encouraging your child to drink at least 2 to 3 liters of noncaffeinated, clear liquids each day and to stay well hydrated.
  • increasing the amount of salt in your child's diet - up to 3-5g/d, as compared to the usual recommendation of limiting them to just 1500-2300mg of salt for typical teens.
  • avoiding big meals and instead eating more frequent, but smaller meals (big meals increase the amount of blood in the gut)
  • an exercise or reconditioning program to include aerobic activity and lower body strengthening that gradually increases the amount of exercise your child gets each day. This is especially important since many experts think that bedrest and deconditioning may play a role in actually causing POTS.

Medications are also sometimes used to help teens with POTS, including metoprolol (a beta-blocker), midodrine (an alpha-agonist), or fludrocortisone (a mineralocorticoid that can help increase salt and water retention), etc.

Although older tricyclic antidepressants are thought to make POTS worse, newer SSRI antidepressants are considered a possible treatment.

It may not be a surprise to some that there is no definitive treatment plan for teens with POTS. Some journal articles don't even agree on whether or not some treatments, like beta-blockers or SSRIs, are even helpful. Getting help will likely include some trial and error to find the best treatments that work for your teen with POTS.

What You Need To Know About POTS

  • Although there is no cure for POTS, many teens do seem to outgrow it. At least 500,000 people in the United States are thought to have POTS.
  • Fainting during exercise is a red flag for a serious cause of syncope, especially in kids with a family history of sudden death. An evaluation by your pediatrician and/or a pediatric cardiologist should be done immediately.
  • POTS is sometimes associated with having hypermobility syndrome, a Chiari malformation, or chronic fatigue, etc.
  • A pediatric neurologist can be helpful to diagnose and treat your child with POTS. Specialty POTS clinics are also available in some Children's Hospitals.

Sources

Jarjour, Imad T. Postural Tachycardia Syndrome in Children and Adolescents. Seminars in Pediatric Neurology, Volume 20, Issue 1, March 2013, Pages 18-26.

Johnson JN Postural orthostatic tachycardia syndrome: a clinical review. Pediatr Neurol 2010;42:77–85.

Pilcher, Thomas A, MD. A Teenage Fainter (Dizziness, Syncope, Postural Orthostatic Tachycardia Syndrome). Pediatric Clinics of North America. Volume 61, Issue 1, February 2014, Pages 29–43.

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