Understanding dysautonomia

Estimated reading time: 8 minutes My first real client introduction to dysautonomia and in this case Postural Orthostatic Tachycardia Syndrome (POTS) was back in 2013 when I had a lady join one of my group classes. She told me she would not be able to do any exercises that involved raising her arms above her head as she would faint. She could mitigate this if she was holding a weight in her hands – that would stop the fainting. This makes sense – the autonomic nervous system (ANS) affects blood pressure regulation and blood flow. 

The impact of gravity on blood flow with raised arms could mean that the ANS can’t respond adequately to the increased demands, leading to poor blood flow to the brain. The use of holding weights seemed to help due to increased muscle engagement to stimulate the vascular system, improving her blood flow.

I was very curious about her condition and started to research and learn more about dysautonomia. Now, of course, so many of my clients have some form of dysautonomia. It was no surprise that she also had hEDS – as there is often a relationship between these two conditions.

I was officially diagnosed with POTS a few years ago – my symptoms became much worse after COVID, specifically palpitations and dizziness. I realize I was mildly symptomatic most of my life – hot baths used to make me feel faint due to dilation of the blood vessels and exacerbate the lack of autonomic regulatory function. I still cannot tolerate any kind of sauna or steam bath for the same reasons. I have always struggled with my temperate regulation – it has to be just right. Not too hot and not too cold. I am sure many of you can relate to this too.

There is often a misdiagnosis of this condition sadly as many people are told their racing heart rates and dizzy spells are simply due to anxiety. This can be really damaging as people miss out on appropriate treatments for dysautonomia and POTS due to this misdiagnosis.

The symptoms of dysautonomia can of course make you feel anxious – especially when you are not sure of the cause. Any unexplained illness or symptom could lead to increased stress and anxiety but that does not mean the cause is psychological. Dysautonomia is a physical and physiological condition that is still sadly unrecognized by many healthcare professionals.

Let’s delve deeper into what it is and how it can impact us.

Overview of the Nervous System

The role of the nervous system is to transmit signals between the brain and the body. It does this through the action of nerves. Nerve cells or neurons are the cell bodies that have elongated extensions called axons and dendrites.

Nerves are made of bundles of these axons that transmit signals to and from the brain and spinal cord throughout the body. These can be things like movement (signal from the brain to the body), sensory (sound, odor, taste signals from the body to the brain), or automatic functions like breathing and heart rate (1).

The nervous system comprises the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS is composed of the brain and the spinal cord while the PNS includes all of the nerves that run throughout the body (2).

The autonomic nervous system (ANS) is the part of the PNS and regulates the involuntary functions of the body (3). The autonomic nervous system is composed of the sympathetic nervous system, the parasympathetic nervous system, and the enteric nervous system (3).

Divisions of the Nervous System Credit: Cenveo CC BY 3.0 US

Functions of the autonomic nervous system

The autonomic nervous system plays a role in the function of almost every tissue in the body without conscious control, it is sometimes called the involuntary nervous system. Functions include blood flow, blood pressure, heart rate, breathing, body temperature regulation, digestion, excretion of waste, pupil diameter, immune responses and inflammation, blood sugar regulation, hormone secretion, and more (4).

The ANS is divided anatomically and at a basic level by function.

• The sympathetic nervous system (SNS)
  • Activation of the SNS leads to the “fight or flight” response of increased activity and attention which allows the body to handle stressors (3).
  • This response can include an increase in heart rate and blood pressure, and slowing of digestion (peristalsis, the muscle contractions that occur in the intestines during digestion, stops)( 3).
• The parasympathetic nervous system (PNS)
  • Activation of the PNS results in the “rest and digest” process (3).
  • During the parasympathetic response, heart rate and blood pressure decrease, and digestion restarts (3).
  • The vagus nerve makes up about 75% of the PNS, and it innervates nearly all of the major organs (3).
• The enteric nervous system
  • Can work independently of, but can also send and receive information to the SNS and PNS (3).
  • It is made of reflex pathways that control the functions of the digestive system like muscle contraction/relaxation and blood flow (3).

The SNS and PNS can work together (synergistically), in opposing activity (antagonistically), or independently because some organs are innervated by only the SNS or only the PNS (4). It is a very complex system of regulation.

Interestingly, the sympathetic nervous system plays a role in nociception (or sensing of pain) and it has been suggested that the autonomic nervous system is normally involved in the regulation or inhibition of pain signaling. When this regulation is lost, there can be hyperexcitability of the nerve fibers involved in pain sensation (3).

Connection between dysautonomia and hypermobility

Autonomic nervous system dysfunction or dysautonomia can occur as a result of things like diseases or disorders, spinal cord injury, toxin exposure, or the use of some drugs (4). It can happen as a loss of function (such as reduction of parasympathetic or sympathetic responses) or the gain of function (overactivation of one or both of the ANS branches) (4).

Dysautonomia, and more specifically orthostatic intolerance, has been linked with joint hypermobility and EDS. A 2018 review assessed published research on this connection and despite difficulty in comparing the studies directly due to differences in research methods, they found between 41-100% of people with joint hypermobility/EDS (JH/EDS) report orthostatic symptoms on a regular basis. In the studies that did assess hemodynamics (or blood flow changes with upright posture), there were abnormalities in 56-80% of JH/EDS patients. The authors concluded that there was evidence for increased sympathetic activity and acknowledged the burden and impact on the quality of life this condition can have (5).

The mechanism for this interaction with hypermobility is not clear but Roma, et al. cite some proposed theories including:

• Connective tissue laxity may impact blood vessel tone leading to increased pooling of blood while standing when upright. This can then lead to a secondary increase in heart rate (POTS) and potentially drops in blood pressure (OH)
• Peripheral neuropathy affecting sympathetic nerve fibers
• Adrenergic hyper-responsiveness
• MCAS – excessive histamine release from mast cells

Recognizing symptoms of dysautonomia

Symptoms of dysautonomia depend on the part of the autonomic system that is affected and can vary and include (6):

• Cardiovascular: orthostatic intolerance (sypmtoms when standing upright), fainting, orthostatic hypotension (decreased blood pressure with standing), POTS (Postural Orthostatic Tachycardia)
• Sudomotor function (control of sweat glands): temperature regulation, excessive sweating (hyperhidrosis), lack of sweating (hypohidrosis)
• Digestion: nausea, gastroparesis, constipation, diarrhea
• Urinary system: retention, increased frequency, urgency, incontinence
• Reproductive system: erectile and ejaculatory dysfunction
• Ocular: Pupil dilation, Horner’s syndrome
• Respiratory system: stridor, cough

Symptoms of POTS

POTS is one of the most mentioned forms of dysautonomia in the literature on hypermobility. It is part of the often referred to triad of EDS, MCAS, and POTS . While there are no set criteria for diagnosis most seem to agree that a diagnosis of POTS to be made there must be (7, 8, 9):

• A sustained increase in heart rate of greater than (or equal to) 30 beats per minute in an upright position (some say within 10 minutes, others say longer including a tilt table test). In those aged 12-19 it is 40 beats per minute.
• Long lasting symptoms occurring longer than 3 months (some say 6 months).
• This is an absence of orthostatic hypotension
• There is no other cause for orthostatic tachycardia
• Orthostatic symptoms are present (see below)
• Orthostatic symptoms improve when laying down

Symptoms are present when upright and improve with laying down and can include (6, 7, 8, 9):

• Lightheadedness
• Palpitations
• Generalized weakness
• Loss of consciousness
• Blurred vision
• Fatigue
• Nausea
• Headache
• Brain Fog
• Chest and/or abdominal pain
• Shortness of breath
• Discoloration of hands and feet (blood pooling)

POTS is also associated with gastroparesis and functional gastrointestinal disorders (6,7).

Dr. Blitshteyn hypothesizes POTS may also impact the central nervous system as well as the ANS because many of the symptoms are CNS symptoms including headache, fatigue, chronic dizziness, cognitive dysfunction and sleep disturbances which seems to impact a large portion of POTS patients (9).

While POTS seems to be the most common form of dysautonomia reported with hypermobility, are many other forms of dysautonomia that occur. One might have orthostatic symptoms but not meet the POTS diagnosis with the Tilt Table Test, this is termed Orthostatic Intolerance You can find out more about other forms of dysautonomia from Dysautonomia International.

Management and treatment strategies

There are many strategies you can try to manage dysautonomia:

• Working with a medical professional that specializes in autonomic dysfunction like an autonomic neurologist can be hugely beneficial. Though they are few and far between, Dysautonomia International has a providor directory that may help.
• Occupational Therapy can help manage symptoms of POTS and other forms of Dysautonomia addressing environmental modifications, exercise, pacing, and more (10).  Emily Rich, OT, PhD jointed me recently on the blog to discuss exercise therapy in POTS.
• Working with a dietitian may be beneficial in managing symptoms of dysautonomia:
  • A review of Nutritional Implications in people with Dysautonomia and Hypermobility advocates for individualized diet strategies that can help manage symptoms and fatigue including dietary modifications, supplementation, and managing salt and fluid intake (11). Check out this video with Lorna Ryan for more information on dietary strategies and myths associated with these conditions.
• Compression can help with orthostatic symptoms. A recent study found the greatest benefit in reducing orthostatic symptoms was with abdominal and leg compression, and if full compression wasn’t tolerated abdominal compression was beneficial on it’s own (12).
• Electrolytes and salt to manage hydration and increase blood volume may help. It is best to work with a physician to guide the amount you should take
• Elevating the head of the bed when sleeping can be helpful.
  • It is recommended to elevate the head of the bed by 4-6 inches so that the bed is on a slant, this is different than adding a wedge or pillows. The idea is that the mild orthostatic stress will lead to activation of the renin-angiotensin-aldosterone system leading to salt water retention and fluid expansion of the blood (13).
• Avoiding temperature extremes – too hot, too cold.
• Some find it helpful to lie down with the legs elevated when having acute symptoms
• When standing for any length of time, keep moving. Counterpressure maneuvers like heel raises, walking on the spot, holding onto something and doing ankle circles. Even squeezing the bottom muscles can help when you start to feel faint.
• Some people find eating smaller and more frequent meals instead of large meals helps. After eating, blood flow is directed to the gut and can cause low blood pressure (postprandial hypotension).
• Regular exercise that is appropriate can be really helpful in the management of this condition. I often start with supine exercises before moving to seated and gradually introduce standing work. There is much that can be done to start conditioning the body without exacerbating symptoms. We have a collection of classes in The Zebra Club that can be done supine.
• Mindfulness and meditation can be useful in regulating the nervous system. Keeping a calm breathing pattern so we don’t overbreathe is also important. A respiratory physio can be a good source of training for this.

If you want to try out some gentle and supine movements, this is a great class full of exercises to help nourish and support the parasympathetic nervous system.

FAQ

Can hypermobility cause dysautonomia?

Dysautonomia frequently occurs hypermobility and EDS. While the exact relationship is not known one theory is that the connective tissue laxity can lead to increased laxity of blood vessels and vessel constriction when upright leading to blood pooling. This blood pooling leads to secondary orthostatic symptoms.

What is the root cause of dysautonomia?

There are many different causes and types of dysautonomia. At the root of all of these is an alteration in the function of the parasympathetic and/or sympathetic nervous system. This can be either increased or decreased activity of one or both.

Does dysautonomia ever go away?

If the cause of Dysautonomia can be determined and addressed like in the case of dysautonomia from toxin exposure or medication, it may be possible for it to improve. Generally, many medical and non-medical interventions can help treat symptoms and improve quality of life.

Literature Review/Research by Catherine Nation, MSc, PhD

Works Cited

1. National Institude of Child Health and Human Development – What are the parts of the nervous system. https://www.nichd.nih.gov/health/topics/neuro/conditioninfo/parts
2. Thau, et al. (2022). Anatomy, Central Nervous System. StatPearls. NCBI Bookshelf. National Library of Medicine.
3. Waxenbaum & Varacallo (2019).Anatomy, Autonomic Nervous System – StatPearls – NCBI Bookshelf
4. Wehrwein, et al. (2016) Overview of the Anatomy, Physiology, and Pharmacology of the Autonomic Nervous System. Comprehensive Physiology.
5. Roma, et al (2018). Postural tachycardia syndrome and other forms of orthostatic intolerance in Ehlers-Danlos syndrome. Autonomic Neuroscience: Basic and Clinical.
6. Mathias, et al. (2021). Dysautonomia in the Ehlers–Danlos syndromes and hypermobility spectrum disorders—With a focus on the postural tachycardia syndrome. American Journal of Medical Genetics.
7. Wu & Ho (2024). An overview of Ehlers Danlos syndrome and the link between postural orthostatic tachycardia syndrome and gastrointestinal symptoms with a focus on gastroparesis. Frontiers in Neurology.
8. Raj, et al (2022) Diagnosis and management of postural orthostatic tachycardia syndrome. CMAJ.
9. Blitshteyn, S (2022). Is postural orthostatic tachycardia syndrome (POTS) a central nervous system disorder? Journal of Neurology.
10. Levine, et al. (2021). Occupational Therapy Interventions for Clients with Ehlers-Danlos Syndrome (EDS) in the Presence of Postural Orthostatic Tachycardia Syndrome (POTS). Occupational Therapy in Healthcare.
11. Do, et al. (2021). Nutritional implications of Patients with Dysautonomia and Hypermobility Syndromes.
12. Bourne, et al. (2021). Compression Garment Reduces Orthostatic Tachycardia and Symptoms in Patients With Postural Orthostatic Tachycardia Syndrome
13. Fu and Levine (2018). Exercise and non-pharmacological treatment of POTS. Autonomic Neuroscience: Basic and Clinical.

Jeannie Di Bon

Jeannie Di Bon is a movement therapist, educator and author specializing in hypermobility, Ehlers-Danlos Syndrome and chronic pain. She is the founder of The Zebra Club app and the creator of the Integral Movement Method.