Unveiling 10 Key Facts About Postural Orthostatic Tachycardia Syndrome (POTS)

Postural Orthostatic Tachycardia Syndrome, widely known as POTS, is a complex and often misunderstood condition that impacts millions worldwide. Characterized by an abnormal increase in heart rate upon standing, POTS can manifest a wide array of debilitating symptoms, significantly affecting daily life. For those seeking to understand this condition better, it’s crucial to be informed about the key aspects of POTS. This article aims to shed light on ten essential facts about POTS, drawing from research and expert consensus to provide a comprehensive overview. Understanding these facts is the first step towards better awareness, diagnosis, and management of POTS.

1. POTS is a Disorder of the Autonomic Nervous System

One of the fundamental facts about POTS is its classification as a disorder of the autonomic nervous system (ANS). The ANS is responsible for regulating involuntary bodily functions such as heart rate, blood pressure, digestion, and temperature control. In individuals with POTS, this system malfunctions, particularly in response to changes in posture. Research indicates that a significant portion of POTS patients exhibit signs of autonomic neuropathy. Studies reveal that approximately 50% of POTS patients have sudomotor neuropathy, a condition affecting the nerves that control sweating. Furthermore, around 20% show cardiac dropout on MIBG scans, which may point to cardiac autonomic neuropathy, indicating nerve damage affecting heart function. This autonomic dysfunction is central to understanding the wide-ranging symptoms experienced in POTS.

2. POTS is More Common Than You Might Think

Contrary to being a rare condition, another crucial fact about POTS is its surprisingly high prevalence. It is estimated that POTS affects between 3,000,000 and 6,000,000 Americans. To put this into perspective, this is more prevalent than conditions like multiple sclerosis or Parkinson’s disease. POTS disproportionately affects women, with 80-85% of diagnosed cases being female, particularly women of childbearing age. While POTS is recognized globally, detailed prevalence statistics are not readily available for countries outside the United States, highlighting a need for more global research and awareness. The significant number of individuals affected underscores the importance of recognizing POTS as a substantial health concern.

3. Research Suggests POTS May Be an Autoimmune Condition

Emerging research is uncovering compelling facts about POTS related to autoimmunity. The autoimmune system, which normally defends the body against foreign invaders, mistakenly attacks healthy tissues in autoimmune conditions. In POTS, studies have identified various autoantibodies in patients’ blood. These antibodies target crucial receptors in the body, including alpha1, beta1, and beta2 adrenergic receptors, muscarinic3 receptors, and g-AchR receptors, all of which play vital roles in autonomic function. Additionally, antibodies against numerous cardiac lipid raft proteins have been found in POTS patients, further strengthening the autoimmune link. Currently, preliminary studies are exploring the potential of intravenous immunoglobulin (IVIG) therapy for POTS, a treatment often used for autoimmune disorders, suggesting a promising avenue for future treatments based on this autoimmune understanding.

4. POTS or POTS-Like Symptoms Can Be Secondary to Other Autoimmune Conditions

Expanding on the autoimmune aspect, another important fact about POTS is its potential link to other autoimmune diseases. POTS or POTS-like symptoms can manifest as secondary conditions in individuals already diagnosed with autoimmune disorders. These conditions include well-known autoimmune diseases such as Sjogren’s syndrome, lupus, antiphospholipid syndrome, celiac disease, ankylosing spondylitis, sarcoidosis, Lambert Eaton myasthenic syndrome, myasthenia gravis, and multiple sclerosis. This connection implies that in some cases, POTS might not be a standalone primary condition but rather a complication arising from a broader autoimmune dysfunction. Recognizing this secondary POTS is crucial for patients with autoimmune conditions who may develop unexplained symptoms consistent with POTS.

5. POTS Can Trigger a Wide Range of Symptoms Throughout the Body

One of the most challenging facts about POTS for both patients and clinicians is the sheer diversity of symptoms it can cause. POTS is not just about an increased heart rate; it’s a multisystem disorder. Symptoms can span across various bodily functions, including cardiovascular issues like persistent tachycardia, heart palpitations, and chest pains. Neurological symptoms are common, such as lightheadedness, fainting or near-fainting episodes, migraines, cognitive impairments (often described as “brain fog”), and tremors. Gastrointestinal problems are also frequently reported, including nausea, gastroparesis (delayed stomach emptying), or rapid gastric emptying. Furthermore, POTS can cause blood pooling in the extremities, Raynaud’s phenomenon (abnormal blood vessel constriction in response to cold or stress), and sleep abnormalities. This extensive symptom profile often makes diagnosis complex, as symptoms can mimic those of other conditions.

6. Many POTS Patients Experience Hypovolemia Despite Adequate Hydration

A counterintuitive fact about POTS is that a majority of patients are hypovolemic, meaning they have a reduced blood volume, even when they maintain what seems like adequate fluid intake. Standard blood and urine tests often fail to detect this hypovolemia in POTS patients because the deficiency is typically in both plasma (the liquid part of blood) and red blood cells. This is unlike dehydration, where there’s primarily a loss of water. To accurately assess hypovolemia in POTS, a specialized test called blood volume analysis using a radio-tracer is often necessary. Understanding this underlying blood volume issue is critical because it affects blood pressure regulation and contributes to many POTS symptoms, especially upon standing.

7. POTS is Frequently Misdiagnosed or Dismissed

A deeply concerning fact about POTS is the high rate of misdiagnosis and dismissal that patients experience. The average time from symptom onset to receiving an accurate POTS diagnosis is alarmingly long, nearly six years. Before reaching the correct diagnosis, a staggering 85% of POTS patients report being told that their symptoms are psychological (“it’s all in your head”) or being given psychiatric labels. This dismissal is particularly harmful as research clearly indicates that POTS patients are not more prone to psychiatric disorders than healthy individuals. This diagnostic delay and dismissal not only prolongs patient suffering but also delays access to appropriate management and treatment strategies, highlighting a significant gap in medical understanding and awareness of POTS.

8. POTS is Not Just a Teenage Syndrome, and Teens Don’t Always “Outgrow” It

Challenging common misconceptions is another important set of facts about POTS. It’s a myth that POTS is solely a teenage condition that individuals simply outgrow. While POTS can certainly begin in adolescence, it’s not limited to this age group, and many adults develop POTS as well. A 10-year retrospective study from the Mayo Clinic on pediatric POTS patients revealed that, on average, five years after their initial visit, only 18.2% had fully recovered. A significant 52.8% experienced improved symptoms but still lived with POTS. Furthermore, a survey of 700 POTS patients by Dysautonomia International found that almost half (48%) developed their first POTS symptoms after the age of 18. These findings clearly demonstrate that POTS is not merely a temporary teenage phase and can be a chronic condition affecting individuals of all ages.

9. The Severity of POTS Symptoms Can Vary Significantly

Understanding the spectrum of the condition involves recognizing facts about POTS related to symptom severity. POTS is not a uniform condition; its impact varies greatly from person to person. Approximately 25% of POTS patients experience such severe disability that they are unable to work or attend school. The level of disability caused by POTS has been compared to that seen in serious chronic conditions like Chronic Obstructive Pulmonary Disease (COPD) and congestive heart failure, emphasizing the profound impact POTS can have on an individual’s functional capacity and quality of life. While some individuals may manage their symptoms with lifestyle adjustments and medical treatment, others face significant challenges in performing daily activities due to the debilitating nature of their POTS.

10. Specific Autonomic Function Testing is Essential for Suspected POTS

For individuals suspected of having POTS, it’s a critical fact about POTS that referral for autonomic function testing is necessary for accurate diagnosis. This testing typically includes a tilt table test with heart rate variability monitoring, Valsalva maneuver, and QSART (Quantitative Sudomotor Axon Reflex Test). In certain cases, further investigations may be warranted, such as supine/upright catecholamine testing (measuring stress hormone levels in different postures), blood volume analysis with a radio-tracer (as mentioned earlier), and skin biopsies to check for sudomotor and sensory small fiber neuropathy. Moreover, a comprehensive evaluation should be conducted to identify any underlying or contributing conditions, such as autoimmune disorders, Ehlers-Danlos syndrome (a connective tissue disorder), or mast cell disorders. These tests and investigations are crucial for confirming a POTS diagnosis and for differentiating it from other conditions with similar symptoms, as well as identifying potential triggers or comorbidities.

For those seeking more in-depth information, Dysautonomia International offers a collection of POTS medical journal articles and lectures from experts in the field, such as Dr. Satish Raj, a leading POTS researcher from Vanderbilt University’s Autonomic Dysfunction Center. Understanding these ten key facts about POTS is a vital step toward better recognition, support, and research for this often-debilitating condition.

References

1. Haensch CA, Lerch H, Schlemmer H, Jigalin A, Isenmann S. Cardiac neurotransmission imaging with 123I-meta-iodobenzylguanidine in postural tachycardia syndrome. J Neurol Neurosurg Psychiatry. 2010 Mar;81(3):339-43.
2. Haensch CA, Tosch M, Katona I, Weis J, Isenmann S. Small-fiber neuropathy with cardiac denervation in postural tachycardia syndrome. Muscle Nerve. 2014 Mar 20.
3. Thieben MJ, Sandroni P, Sletten DM, Benrud-Larson LM, Fealey RD, Vernino S, Lennon VA, Shen WK, Low PA. Postural orthostatic tachycardia syndrome: the Mayo clinic experience. Mayo Clin Proc. 2007 Mar;82(3):308-13.
4. Peltier AC, Garland E, Raj SR, Sato K, Black B, Song Y, Wang L, Biaggioni I, Diedrich A, Robertson D. Distal Sudomotor Findings in Postural Tachycardia Syndrome. Clin Auton Res. Apr 2010; 20(2): 93-99.
5. Fu Q, VanGundy TB, Shigeki S, Auchus RJ, William GH, Levine BD. Menstrual Cycle Affects Renal-Adrenal and Hemodynamic Responses during Prolonged Standing in the Postural Orthostatic Tachycardia Syndrome. Hypertension. July 2010; 56(1): 82-90.
6. Kanjwal K, Saeed B, Karabin B, Kanjwal Y, Grubb BP. Use of methylphenidate in the treatment of patients suffering from refractory postural tachycardia syndrome. Am J Ther. 2012 Jan;19(1):2-6.
7. Mustafa H, Raj SR, Diedrich A, Black B, Paranjape SY, Dupont WD, Williams GH, Biaggioni I, Robertson D. Altered Systemic Hemodynamic & Baroreflex Response to Angiotensin II in Postural Tachycardia Syndrome. Circ Arrhythm Electrophysiol. Feb 2012; 5(1): 173-180.
8. Robertson D. The Epidemic of Orthostatic Tachycardia and Orthostatic Intolerance. The American Journal of the Medical Sciences. Vol. 317(2) February 1999: 75-77.
9. Grubb BP. Postural Tachycardia Syndrome. Circulation. 2008; 117: 2814-2817.
10. Brooks J, Francis L. Postural orthostatic tachycardia syndrome Dental treatment considerations. Journal of the American Dental Association. Vol. 137, April 2006.
11. Garland EM, Raj SR, Black BK, Harris PA, Robertson D. The hemodynamic and neurohumoral phenotype of postural tachycardia syndrome. Neurology 2007;69:790-798.
12. Raj SR. The Postural Tachycardia Syndrome (POTS): Pathophysiology, Diagnosis & Management. Indian Pacing Electrophysiol J. 2006 Apr-Jun; 6(2): 84-99.
13. Li H, Yu X, Liles C, Khan M, Vanderlinde-Wood M, Galloway A, Zillner C, Benbrook A, Reim S, Collier D, Hill M, Raj SR, Okamoto LE, Cunningham MW, Aston CE, Kem DC. Autoimmune Basis for Postural Tachycardia Syndrome. J Amer Heart Assoc. 2014:3.
14. Sandroni P, Low PA. Other Autonomic Neuropathies Associated with Ganglionic Antibody. Auton Neurosci. Mar 12, 2009; 146(1): 13-17.
15. Wang XL, Ling TY, Charlesworth MC, Figueroa JJ, Low P, Shen WK, Lee HC. Autoimmunoreactive IgGs against cardiac lipid raft-associated proteins in patients with postural orthostatic tachycardia syndrome. Transl Res. 2013 Jul;162(1):34-44.
16. Personal communications between Dysautonomia International Board members and Dr. Hasan Abdallah at The Children’s Heart Institute in Reston, Virginia, Dr. Brent Goodman at the Mayo Clinic in Scottsdale, Arizona and Dr. David Kem at the Univeristy of Oklahoma Health Sciences Center in Oklahoma City, Oklahoma.
17. Gibbons CH, Freeman R. Autonomic neuropathy and coeliac disease. J Neurol Neurosurg Psychiatry 2005;76:579-581.
18. Kaya MG, Akpek M, Lam YY, Dogdu O, Ardic I, Akgul O, Ozgocmen S. Abnormal heart rate recovery on exercise in ankylosing spondylitis. Int J Cardiol. 2013 Nov 5;169(3):215-8.
19. Schofield JR, Blitshteyn S, Shoefeld Y, Hughes GRV. Postural tachycardia syndrome (POTS) and other autonomic disorders in antiphospholipid (Hughes) syndrome (APS). Lupus. February 25, 2014.
20. Evoli A, Liguori R, Romani A, Mantegazza R, Di Muzio A, Giometta B, Pergoraro E, Rodolico C, Vigliani MC. Italian recommendations for Lambert-Eaton myasthenic syndrome (LEMS) management. Neurol Sci. 2014 Apr; 35(4): 515-20.
21. Calin C, Savu O, Dumitru D, Ghiorghiu I, Calin A, Capraru C, Popescu BA, Croitoru M, Vilciu C, Ginghina C. Cardiac Involvement in Myasthenia Gravis ? Is There a Specific Pattern? Rom J. Intern. Med. 2009; 47(2): 179-189.
22. Kanjwal K, Karabin B, Kanjwal Y, Grubb BP. Autonomic Dysfunction Presenting as Postural Orthostatic Tachycardia Syndrome in Patients with Multiple Sclerosis. Int J Med Sci. 2010; 7(2): 62-67.
23. Ojha A, Chelimsky TC, Chelimsky G. Comorbidities in pediatric patients with postural orthostatic tachycardia syndrome. J Pediatr. 2011 Jan; 158(1): 20-3.
24. Raj SR, Biaggioni I, Yamhure PC, Black B, Paranjape SY, Byrne D, Robertson D. Renin-Aldosterone Paradox and Perturbed Blood Volume Regulation Underlying Postural Tachycardia Syndrome. Circulation. 2005; 111: 1574-1582.
25. Dysautonomia International Report: Physician Patient Interaction in Postural Orthostatic Tachycardia Syndrome; publication pending. E-mail [email protected] to receive a copy once the report is published.
26. Wagner C, Isenmann S, Ringendahl H, Haensch CA. Anxiety in patients with postural tachycardia syndrome (POTS) [Article in German]. Fortschr Neurol Psychiatr. 2012 Aug; 80(8): 458-62.
27. Raj V, Hama K, Raj SR, Byrne D, Blakely RD, Biaggioni I, Robertson I, Shelton RC. Psychiatric Profile and Attention Deficits in Postural Tachycardia Syndrome. J Neurol Neurosurg Psychiatry. Mar 2009; 80(3): 339-344.
28. Kizilbash SJ, Ahrens SP, Bhatia R, Killian JM, Kimmes SA, Knoebel EE, Muppa P, Weaver AL, Fischer PR. Long-term outcomes of adolescent-onset postural orthostatic tachycardia syndrome. Presented at the 24th International Symposium on the Autonomic Nervous System, Kohala Coast, Hawaii, October 23, 2013.
29. Wallman D, Weinberg J, Hohler AD. Ehlers-Danlos Syndrome and Postural Tachycardia Syndrome: A relationship study. J Neurol Sci. 2014 Mar 11. pii: S0022-510X(14)00145-2.
30. Shibao C, Arzubiaga C, Roberts J, Raj S, Black B, Harris P, Biaggioni I. Hyperadrenergic Postural Tachycardia Syndrome in Mast Cell Activation Disorders. Hypertension. 2005; 45: 385-390.
31. Mar M, Raj S. Neuronal and hormonal perturbations in postural tachycardia syndrome Front Physiol. 2014; 5: 220.
32. Stiles LE, Ross AJ. Physician Patient Interaction in Postural Orthostatic Tachycardia Syndrome. Dysautonomia International. July 2014.