WHAT IS P.O.T.S.? - Part I

P.O.T.S. (Postural Orthostatic Tachycardia Syndrome) is a disorder of the autonomic nervous system.  The autonomic nervous system controls all of the involuntary functions of your body, like breathing, blood pressure, heart beat, digestion, etc.  These are the things that keep you alive, that you normally don't have to think about.  When you eat a cheeseburger, you don't tell your stomach, "O.K. stomach, let's get to work and digest that cheeseburger."  Your stomach does it for you, because it is controlled by your autonomic nervous system.

People with POTS have a problem with one or more parts of their autonomic nervous system.  Since the autonomic nervous system is so important to good health, people with POTS can suffer from a long list of symptoms that can impact every system in the body, including the respiratory, cardiac, nervous, endocrine, reproductive and immune systems.

The formal diagnostic criteria for POTS are as follows:
"the presence of symptoms of orthostatic intolerance associated with a heart rate increase of 30 bpm (or rate that exceeds 120 bpm) that occurs within the first 10 minutes of standing or upright tilt, not associated with other chronic debilitating conditions such as prolonged bed rest or the use of medications known to diminish vascular or autonomic tone." Dr. Blair Grubb, Postural Tachycardia Syndrome. Circulation 2008;117;2814-2817.  A recent consensus statement from experts in the field of autonomic disorders indicates that a heart beat increase of 40 beats per minute or more is required to diagnose POTS in pediatric patients.

The "S" in POTS stands for "Syndrome" because doctors don't really know what exactly causes POTS in every patient, although they have good theories.  The medical community calls a list of symptoms that are related and commonly seen together a "syndrome" to help with diagnosis, but there is no definitive answer at this time on what causes POTS in each patient.  POTS was only recognized as a syndrome and given a name by researchers at the Mayo Clinic in 1993, however other researchers had described its symptoms under various terms since the 1940s. 

While each case is unique, some of the known causes of POTS include Lyme Disease, viral infections (especially Epstein Barr Virus), genetic disorders, connective tissue disorders, autoimmune diseases, thyroid and other hormonal imbalances, mitochondrial disorders, Chiari brainstem malformation, and physical traumas/accidents.  Currently,  over 500,000 Americans have been diagnosed with POTS.  POTS researchers at Mayo Clinic estimate that another 500,000 patients in the U.S. have POTS, but have not been properly diagnosed.  About 80% of the patients are women, and most are relatively young.  POTS researchers estimate that 1 in 100 teenage girls will develop POTS before adulthood.

Since most doctors, even specialists at major medical centers, have not heard of POTS, it can be very hard for POTS patients to get properly diagnosed.  The average POTS patient takes several years to get properly diagnosed, and most patients have been misdiagnosed and even treated for health problems they did not have before being accurately diagnosed with POTS.  For example, it took me 9 months to get diagnosed with autonomic nerve damage and POTS and then another 10 months to figure out the cause of the nerve damage - an autoimmune disease that is attacking my nerves called Sjogren's Syndrome.  Before my doctors figured this out, I was misdiagnosed with everything from croup, to Addison's Disease to cancer (and given strong medications and chemo to treat these incorrect diagnoses).

There is currently no cure for POTS.  The disabling symptoms caused by POTS are repoted to be similar to living with congestive heart failure or COPD.  I can attest to that as my grandmother had COPD and emphysema, and I am usually more restricted in my daily acitivies than she was at 89 years old.  Many POTS patients cannot work and have a significantly reduced quality of life from their pre-POTS lifestyle.  Some POTS patients have had symptoms since birth, but most patients were active and healthy until something triggered a sudden onset of POTS.  

Recovery statistics are lacking.  One research paper found that about 50% of patients who develop POTS as a result of an viral infection (such as Epstein Barr) will recover or almost fully recover within 5 years of the onset of POTS.  There are no statistics on how many additional post-viral POTS patients will improve or recover after the 5 year mark, whether any of the 50% who have recovered will have a relapse of POTS (although this seems to be somewhat common amongst patients I have met online) or what the prognosis is for patients with POTS that is not post-viral, because researchers have not done any long term studies on these questions.  

There are a number of drugs and therapies available to help improve symptoms in POTS patients, although most patients still have difficulties with day to day tasks even with all treatment modalities being utilized.

Here's a partial list POTS symptoms I've had, which are all caused by the nerve damage caused by Sjogren's Syndrome.  For the record, I did not have any of these problems before I got really sick in January 2010.  Before all of this I was a healthy, active, athletic person.  I was actually on a ski trip in VT cross-country skiing uphill and flying through the moguls on my snowboard just a few days before I developed POTS.  Please don't think I'm whining  and looking for sympathy by posting this symptom list.  I want to put this information out there so that other POTS patients know they are not alone in what they are going through.  Also, maybe someone reading this will recognize these symptoms in someone they know and help that person get properly diagnosed with POTS or Sjogren's Syndrome.  Here's my partial symptom list:

-Severe Tachycardia - rapid heart beat, especially when standing up

-Abnormal increase in heart rate upon standing - my heart beat increases 30 beats per minute (bpm) or more upon standing .  I am usually 70-80 bpm when laying down and then 130 to 160 bpm as soon as I stand up, and it keeps going up the longer I stand up.  My highest recorded bpm, just standing up and not moving, was 230.  It feels like my chest is going to explode.

-Low blood pressure - laying down, my blood pressure can go as low as 80/30.  If I stand up, it drops even lower and then I pass out.  Sometimes they can't even get a reading on my blood pressure when I stand up because the machines cannot detect blood pressure when it is that low.

-Lightheadedness and dizziness (from the low blood pressure)

-Vertigo  - this is different that dizziness - for you older readers, vertigo is that spinning/swirling feeling you get when lay down after you've had too much alcohol - in college we called it "the spins."

-Fainting (also called syncope) - before I was properly diagnosed and given medications to increase my blood pressure, I was passing out one or more times per day everyday for about 9 months.  Not fun!

-Almost fainting (pre-syncope) - my pre-syncope symptoms include temporary loss of hearing and vision, sweating, uncontrollable shaking, vertigo and my legs just giving out on me.

-Severe shortness of breath

-Rapid breathing/hyperventilation that is not due to an emotional trigger (it's due to low blood volume).

-Sharp chests pain in various places all over the front of my chest cavity

-Sharp sudden stabbing pains and also dull aching/pressure pain all over my back, especially near the back of my armpits, between my shoulder blades and along the bottom of my rib cage in the back.

-Aching/sore neck and shoulders

-Tightness in my chest and throat that makes it hard to breathe

-Horrible night sweats (your autonomic system controls your temperature, so it's like my thermostat is broken)

-Heart palpitations

-A really annoying thumping feeling of my heartbeat in my stomach, chest, neck, ears, eyes, thighs and fingers (caused by a combo of the low blood pressure and low blood volume)

-A very noticeable sinus arrhythmia (a sinus arrhythmia is when your heart beats faster as you breathe in, and slower as you breathe out - it is considered normal in healthy people, but mine has become more exaggerated since I developed POTS)

-Seeing my pulse flash in my eyes, even when they are closed and I am in a dark room.

-Extreme fatigue (as in, laying in bed for a week straight and not being able to go downstairs to get a glass of water)

-Despite being tired, I can't sleep (try sleeping when you're heart is beating 130 bpm and your pulse is flashing in your eyes!)

-Temperature sensitivity (getting REALLY cold and shivering when it's not even that cold out, getting REALLY hot and sweating when it's not that hot, taking along time to recover from being too cold or too hot, not being able to take a hot shower)

-Abdominal pain of every kind (because the nerves controlling my GI tract are damaged)

-Bloating, even after eating small, healthy meals

-Feeling dizzy/lightheaded after eating (doctors call this post-prandial hypotension-it's because the blood is pooling in your belly to help digest your food)

-Getting the full body chills after eating, and no amount of blankets or hot tea will make it go away.

-Acid reflux/GERD  that cannot be relived by anti-reflux medications.

-Vomiting several times per day, even when you don't eat (thankfully this stopped after about 3 months)

-Diarrhea - I'm not going to be shy about this.  This is too important to leave out because it made me really sick.  I was getting it several times a day for months and months and I started to get malnourished, which can create very serious complications for someone who is already sick.  I was so malnourished from this, that my hair started falling out and I developed all sorts of vitamin deficiencies.

-Sudden weight loss  - I lost 60 lbs. in a few months, but I've gain about 10 back now.  I have to eat about 3000 calories per day just to maintain my weight.

-Random shooting/stabbing electric bolt like pains in my head, face, chest, and legs that actually make me scream out loud and drop to the floor, whatever I'm doing.  I've crumbled to the kitchen floor enough times to consider getting carpeting in the kitchen.  Tile hurts.

-Oversensitivity to pain and touch - When this symptom was really bad, I didn't even like getting hugged because it hurt and it seemed to overstimulate me.  The needles for the hundreds of blood tests I had were torture, even though I never had any problems donating blood or getting shots in the past.

-Oversensitivity to noise - I'd jump out of my chair if someone knocked on the door or if my dog barked, and I'd get headaches very easily from quietly watching TV or listening to my I-Pod.

-Photosensitivity - I get burning eyes, dizziness and headaches in bright light and sudden flashes of light make me very dizzy.

-The skin on my legs turns blotchy and purple if I stand up for a few minutes, and every time I take a bath (I can't stand in the shower most days).  This is caused by blood pooling in my legs.

-Flushing  - my arms, upper chest and face turn purplish red.  Doctors think this is caused by inappropriate blood flow and vein constriction.

-Worsened allergies  - I always had mild allergies since I was a kid, normal stuff like dust mites and dog dander, but never needed medication for them and never had any food allergies.  I spent the first six months of POTS on allergy meds everyday and now I have to carry an Epi-Pen around with me.

-Lactose intolerance for the first time in my life (and I'm a cheese addict!)

-Gluten intolerance for the first time in my life (and what goes better with cheese than bread?)

-Chemical/drug sensitivities - if the recommended adult dose for a medicine is 10 mg, I probably only need 1 mg even though I'm a 6 ft tall adult.

-Irregular menstrual cycles and a worsening of most of the other POTS symptoms before and during menstruation.

-Pins and needles/tingling/creepy crawly skin sensations (especially when I'm given medications that effect the nervous system).

-Dry mouth, eyes and skin despite the fact that I'm consuming 2-3 liters of water and juice per day

-Frequent infections/weakened immune system.  I had a constant sore throat for 11 months.  I've also had several unusual small cysts on my skin, which my dermatologist said were infected with a common and normal skin bacteria.

-Terrible fatigue, especially in the morning.  All of my symptoms tend to be worse in the morning, until about 3PM when I start to come alive a little bit. 

-Forgetfulness/spaced out feeling

-Easily distracted/hard to focus my eyes

-Not being able to find the word you're trying to say (doctors would call this recall or cognitive impairment)

-Dilated pupils, even in bright light - When they get really big, I look like anime cartoon character.  Sometimes they are dilated unevenly, the left pupil is huge and the right is small, which is kind of creepy.  Whenever my pupils act up, it causes vertigo so bad I can't move without tripping.

-Heightened senses  - I'm the first one to smell something weird, or to hear a strange noise in the distance, or to taste that milk has started to spoil.  I feel like the proverbial canary in the coal mine.

-Hyperreflexia  - my reflexes are on overdrive.  When the doctors poke my knee with that rubber mallet, I actually kick so hard that I've hurt two doctors.  Kind of funny.

There are many more symptoms associated with POTS, and each POTS patient seems to present in their own unique way.  There are some POTS patients much worse off than me, who are completely bedridden for years and have to eat through feeding tubes because the autonomic nerves controlling their digestive tracts are totally destroyed.  There are others who are doing fairly well, and have been able to return to school and work.

If you'd like to know WHY some of these symptoms are occurring, check out my What is POTS-Part II post.