Both of these conditions lend much too readily to hypovolemia (low blood volume) from a variety of reasons: stretchy bladders making us pee out more than we take in, impinged nerves and tethered cord lending to incontinence, MCAD reactions adding to frequent urination (and increased bladder volume), MCAD causing vaso-dilation and third-spacing thus lowering blood volume further, to name a few. I.e, we “leak” easily in many ways.
Toss in weak valves and flaccid veins thanks to weak connective tissues, and it’s just not a surprise to find POTS so highly comorbid in our community. Not 1:1 (1 to 1) no, but definitely some form of dysautonomia at the very least.
Then, impinged neurology (Chiari, CCI) and or incomplete ennervation (demyelinated nerves, incomplete nerves) can lend to additional trouble that does not act like POTS at all. (Sudden BP spikes or drops not driven by MCAS, also oxygen problems.) Some of the more rare types of EDS can lend to this – especially “classic like EDS”, a.k.a. “clEDS”. (Not the same as Classical EDS, cEDS, though it resembles it at first glance, whence its name.) I know some who feel very little/no pain, and thus injure more dangerously. But also can’t regulate their BP and oxygen properly either from this. It is often labeled “Familial Dysautonomia“* and can flare up after a bad viral illness in some.
* This does not mean you have POTS running in your family. it is a distinct, different form of dysautonomia involving incomplete or insufficient ennervation of the body. And, you can have both POTS and FD. I know someone who does.
Also, your condition can vary, flaring and easing up from a variety of causes including stress, trauma, viral (or other) serious illness, MCAD, and hormone changes especially in women. (Progesterone makes you more lax, and both estrogen and progesterone are mast cell triggers it turns out alas.) Toss in highly comorbid (but technically unrelated) auto-immune disease (and possible causes) and POTS just is no longer a surprise any more.
Please know some will have a Hyperadrenergic variant that requires special treatment different from the “regular” variety. And, technically and apparently some people can actually just have POTS and other forms of dysautonomia in the absence of a connective tissue disorder, though I’ve yet to meet any. Just allowing for this possibility and understanding.
And like all of our issues, it is also quite tricky to diagnose, and yet another “heavy lift” as doctors have only been told about the grossest signs of the rarest types, and will often dismiss milder cases as “just anxiety” or depression or hypochondria. You may end up seeing either a cardiologist, or a neurologist, or both along the way.
Please trust your gut and body and continue playing gently but firmly squeaky wheel if you suspect the condition. You deserve the improved quality of life to be had from proper treatment for this very disabling condition. And there is help and hope for it, but like everything we enjoy, think “marathon” not sprint.