Understanding Dysautonomia and Orthostatic Intolerance: Types, Symptoms, Diagnosis, and Treatment Options
October is Dysautonomia Awareness Month!
Have you ever heard of the term "autonomic nervous system"? This crucial part of your body is always working in the background, controlling essential functions like your heart rate, digestion, and breathing. But what happens when it doesn’t work properly? This is what we call “dysautonomia”.
Dysautonomia: When Your Body's Autonomic Nervous System Loses Control
What is the Autonomic Nervous System?
The autonomic nervous system (ANS) is a branch of your nervous system responsible for regulating your subconscious bodily functions. It’s like the body’s autopilot, ensuring that your heart beats at the right pace, your blood pressure is regulated, your lungs take in oxygen, and your digestive system processes food—all without you having to think about it. It operates without conscious effort to maintain homeostasis (your body's stable internal environment).
The ANS has two divisions: the sympathetic and the parasympathetic. These two branches work in tandem to ensure your body responds appropriately to different situations, whether it’s ramping up for action or winding down for rest.
Sympathetic Nervous System: This is your body’s “fight or flight” response. When you’re stressed or in danger, it kicks in to increase your heart rate, open your airways, and direct blood flow to muscles, preparing you to react quickly.
Parasympathetic Nervous System: This is the “rest and digest” system, associated with the vagus nerve. It helps slow your heart rate, promotes digestion, and conserves energy when you’re relaxed.
Functions of the Autonomic Nervous System
The autonomic nervous system is a multitasking marvel, performing several critical functions to keep your body running smoothly. The sympathetic nervous system is your body’s “fight or flight” mechanism, kicking in during stressful situations to prepare you for action. On the other hand, the parasympathetic nervous system is responsible for “rest and digest” activities, promoting relaxation and recovery. Additionally, the ANS includes the enteric nervous system, which specifically manages the functions of the digestive system, ensuring that everything from nutrient absorption to waste elimination runs smoothly.
Here are some of the ANS's key roles:
Regulating Heart Rate and Blood Pressure: Ensuring your heart beats at the right pace and your blood pressure stays within a healthy range.
Controlling Digestion and Gut Motility: Managing the process of breaking down food and moving it through your digestive tract.
Modulating Body Temperature: Helping your body maintain a stable temperature, whether you’re in a hot or cold environment.
Regulating Sweating and Salivation: Controlling sweat production to cool you down and saliva production to aid in digestion.
Controlling the Diameter of Blood Vessels: Adjusting blood vessel size to regulate blood flow and pressure.
Regulating the Function of the Urinary and Reproductive Systems: Ensuring these systems operate efficiently and helping to maintain blood volume through kidney function
Modulating the Immune System: Playing a role in your body’s defense mechanisms.
What is Dysautonomia?
Types of Dysautonomia
Dysautonomia encompasses a variety of conditions that affect the ANS. Each condition has unique characteristics and impacts the body differently. Here are some of the different types of dysautonomia, ranging from relatively common to extremely rare.
Orthostatic Hypotension (OH): This condition occurs when blood pressure drops significantly upon standing, leading to dizziness, lightheadedness, and sometimes fainting. The body struggles to adjust blood flow quickly enough when upright.
Vasovagal Syncope: A common cause of fainting triggered by a sudden drop in heart rate and blood pressure, often due to stress, pain, or prolonged standing. It leads to reduced blood flow to the brain, causing a brief loss of consciousness.
Neurocardiogenic Syncope: A type of syncope similar to vasovagal syncope, where the body’s nervous system and heart miscommunicate, causing fainting due to a sudden drop in blood pressure and heart rate.
Postural Orthostatic Tachycardia Syndrome (POTS): This condition is marked by an abnormally high increase in heart rate when standing up, often leading to dizziness, fatigue, and sometimes fainting. POTS can significantly affect daily activities and is more common in younger individuals (check out more about how we help with POTS here)
Inappropriate Sinus Tachycardia: A form of dysautonomia where the heart beats excessively fast, even when at rest or with minimal exertion, without an obvious cause. This can lead to palpitations, dizziness, and fatigue.
Autoimmune Autonomic Ganglionopathy: A rare disorder where the body’s immune system attacks parts of the autonomic nervous system, causing symptoms like severe orthostatic hypotension, abnormal sweating, and gastrointestinal dysfunction.
Multiple System Atrophy (MSA): A rare, progressive neurodegenerative disorder affecting multiple parts of the nervous system, including the autonomic nervous system (ANS). Symptoms include severe fluctuations in blood pressure, bladder dysfunction, and motor impairments.
Pure Autonomic Failure (PAF): A rare disorder where the autonomic nervous system gradually loses its ability to regulate bodily functions. Symptoms include severe orthostatic hypotension, problems with urination, and reduced sweating.
Familial Dysautonomia (FD): A genetic disorder that affects the development and function of the autonomic and sensory nervous systems. It primarily affects individuals of Ashkenazi Jewish descent and can cause symptoms such as blood pressure instability and gastrointestinal issues.
Chronic Autonomic Failure: This condition is associated with disorders such as Parkinson's syndrome and idiopathic orthostatic hypotension. Autonomic deficits impact blood pressure regulation, leading to postural hypotension.
Each of these conditions represents a form of dysautonomia, where the autonomic nervous system does not function properly, leading to a variety of symptoms that affect everyday activities and well-being. Understanding the specific type of dysautonomia is crucial for effective management and treatment.
Causes and Risk Factors for Dysautonomia
Dysautonomia can be caused by a variety of factors, and may occur as the result of a primary dysautonomic condition, but secondary dysautonomia can also be caused by other diseases or conditions that affect the autonomic nervous system. While the exact causes can vary depending on the specific type of dysautonomia, there are several common risk factors that can increase the likelihood of developing the condition:
Genetics
Some forms of dysautonomia are inherited genetic conditions. A family history of autonomic nervous system disorders may increase the risk of certain dysautonomia types.
Autoimmune Disorders
People with autoimmune diseases, such as Lupus, Sjogren’s Syndrome, or Multiple Sclerosis, are at a higher risk of developing dysautonomia. In these conditions, the immune system mistakenly attacks parts of the body, including the autonomic nervous system.
Viral Infections
Infections, particularly severe or chronic viral infections, can trigger dysautonomia. Some viruses, like Epstein-Barr Virus (EBV) and COVID-19 have been linked to the onset of Postural Orthostatic Tachycardia Syndrome (POTS) or other forms of autonomic dysfunction. Viral infections can damage the nerves or trigger autoimmune responses that affect the ANS.
Chronic Illnesses
Conditions like Diabetes and Parkinson’s Disease are significant risk factors for dysautonomia. Diabetes can damage the nerves that control autonomic functions (a condition known as diabetic autonomic neuropathy). Diabetes can lead to autonomic nervous system dysfunction, manifesting symptoms such as orthostatic hypotension and dysautonomic bowel function, complicating diagnosis and impacting overall health. Parkinson’s can affect multiple parts of the nervous system, including the autonomic nerves. Other conditions like fibromyalgia, irritable bowel syndrome, obstructive sleep apnoea, insomnia and migraine are also associated with symptoms of dysautonomia.
Trauma or Injury
Physical trauma, especially to the brain or spinal cord, can disrupt autonomic function. Spinal cord injury can lead to potentially life threatening forms of dysautonomia, including Autonomic Dysreflexia. Injuries resulting in damage to the nervous system generally can lead to conditions like Neurocardiogenic Syncope or other forms of dysautonomia.
Ehlers-Danlos Syndrome (EDS) and Hypermobility Spectrum Disorders
People with joint hypermobility syndromes, including Ehlers-Danlos Syndrome, are more likely to develop dysautonomia, particularly POTS. It is thought that this is because the connective tissue in blood vessels may not function correctly, meaning the ‘squeeze’ reflex is less effective and blood pressure is more difficult to maintain when standing up.
Aging
While some forms of dyautonomia are also very common in younger people, some forms of dysautonomia are more common in older adults. As the nervous system ages, it may not regulate autonomic functions as efficiently, leading to these symptoms of dysautonomia
Gender & Hormonal Differences
Women are more frequently diagnosed with certain types of dysautonomia, particularly POTS. Hormonal differences, especially during times like pregnancy or menstruation, may play a role in increasing the risk.
Physical Deconditioning
People who are bedridden or have had long periods of physical inactivity due to illness or injury are at higher risk of developing dysautonomia. Physical deconditioning can affect blood circulation and how the autonomic nervous system regulates blood pressure and heart rate. It can also impact systolic blood pressure and the cardiovascular system's response to sympathetic stimulation, leading to variability in responses under different conditions. Fun fact - after returning from space, some astronauts develop POTS because their bodies, having adapted to weightlessness, struggle to readjust to Earth’s gravity. It takes time for their nervous system to readapt to compensate for gravity.
Chronic Fatigue Syndrome (ME/CFS) / Long COVID
Dysautonomia is often associated with Chronic Fatigue Syndrome (ME/CFS) and Long COVID. People with CFS frequently experience symptoms of orthostatic intolerance, including lightheadedness, rapid heart rate, and fatigue upon standing.
Symptoms of Dysautonomia
When the autonomic nervous system doesn’t work properly, it can cause a wide range of symptoms depending on which part of the system is affected. Symptoms of dysautonomia can also range in severity from relatively mild to debilitating. Common autonomic symptoms include:
Dizziness, lightheadedness, blurry vision, brain fog, fainting
Pronounced fatigue
Abnormally fast or slow heart rate, heart palpitations, and chest pain
Abnormally high or low blood pressure
Gastrointestinal issues, nausea and vomiting, bladder and bowel symptoms
Sexual dysfunction
Dry mouth and eyes
Abnormal circulation (Reynaud’s disease)
Abnormal sweating and difficulty regulating body temperature
Anxiety and sleep disturbances
The autonomic nervous system also helps your body adjust quickly when you stand up. Dysautonomia is frequently associated with orthostatic intolerance (OI), an issue where symptoms worsen in upright positions.
What is Orthostatic Intolerance?
Orthostatic intolerance (OI) describes an intolerance to being in upright positions due to worsening of symptoms. It can cause a range of symptoms, including fainting or milder cognitive issues like memory problems, difficulty focusing, or slower thinking. Other symptoms can involve vision disturbances, feeling lightheaded, headaches, fatigue, or even fluctuations in blood pressure—either too high (hypertension) or too low (hypotension). Some people might also feel weak, nauseous, or have stomach pain. Additional symptoms can include sweating, shakiness, and difficulty exercising due to feeling easily worn out.
The best way to diagnose orthostatic intolerance (OI) is often through a thorough medical history, especially if symptoms improve when lying down. Doctors may use orthostatic stress tests to trigger OI, for example, tilt table tests—where a patient is moved into an upright posture without being able to use their muscles—or standing tests like the NASA Lean Test. Additional, more complex tests may be conducted to rule out other potential causes of symptoms.
Are there different types of orthostatic intolerance?
Like dysautonomia, orthostatic intolerance is an umbrella term that includes several subtypes and conditions. Mild temporary orthostatic intolerance can happen to anyone, especially during illnesses, if you are dehydrated, or when you stand up too fast. These symptoms usually go away very quickly and aren’t usually too much of a problem. However, there are several types of dysautonomia that fall under the OI banner, including:
Orthostatic Hypotension (OH)
OH occurs when the body is unable to maintain blood pressure on standing - this might be due to the reflexes that help contract the blood vessels in the arms and legs and force blood back to the body not working quite right, or due to reduced blood volume. This makes it difficult for enough blood to return to the brain and can lead to symptoms like dizziness and fainting.
Neurocardiogenic Syncope (NCS)
Syncope is the general medical term for fainting. Also known as vasovagal syncope, NCS causes sudden drops in heart rate and blood pressure, leading to fainting. Triggers can include orthostatic hypotension due to prolonged standing, or other triggers including stress, pain, or other ‘shocks to the system’.
Postural Orthostatic Tachycardia Syndrome (POTS)
POTS is a condition where your heart rate increases abnormally when you move from lying down to standing up. People with POTS experience a rapid increase in heart rate (often 30 beats per minute or more), causing symptoms like dizziness, lightheadedness, chest pain, shortness of breath, fatigue, vision changes, neck and shoulder pain, blood pooling and circulation issues in the hands and feet, and sweating. Unlike syncope, fainting isn’t always present in POTS, but people often experience ‘drop attacks’ which appears similar to fainting but does not result in full loss of consciousness. POTS is often seen in younger individuals, especially women, and has been closely linked to conditions like Chronic Fatigue Syndrome (ME/CFS) and Long COVID.
When to Seek Medical Help
As many symptoms of dysautonomia can also be caused by other, potentially serious conditions, it is important to seek medical attention to ensure that any concerns are investigated and managed appropriately. Here are some signs that warrant an urgent visit to your healthcare provider:
Sudden Changes in Blood Pressure or Heart Rate
Persistent or Severe Dizziness or Lightheadedness
Fainting
Chest Pain or Shortness of Breath
Severe Abdominal Pain or Vomiting
Difficulty Urinating or Bowel Movements
Severe Fatigue or Weakness
Diagnosis and Testing for Dysautonomia
Diagnosis of dysautonomia often involves physical examination and detailed medical history, as well as specific tests like a tilt table test, breathing tests, sweat tests, and bloodwork. As there are many different types of dysautonomia that have different mechanisms and causes, they are all diagnosed differently. Other testing may be needed to evaluate other possible explanations for symptoms to help diagnose dysautonomia. Imaging tests such as MRI or CT scans may also be used to rule out other conditions. A healthcare provider may also use a symptom journal to track symptoms and monitor progress.
Impact on Daily Life
Dysautonomia can have a significant impact on daily life, affecting not only the individual but also their family and friends. Some ways dysautonomia can impact daily life include:
Fatigue and exhaustion: Dysautonomia can cause persistent fatigue and exhaustion, making it difficult to perform daily tasks and maintain a regular routine.
Social isolation: Dysautonomia can lead to social isolation, as individuals may avoid social situations due to fear of exacerbating symptoms or experiencing embarrassing episodes.
Career and education: Dysautonomia can impact career and education goals, as individuals may need to take frequent breaks or adjust their work or school schedule to manage symptoms, or be limited by cognitive fatigue.
Relationships: Dysautonomia can strain relationships with family and friends, as individuals may become withdrawn or irritable due to the challenges of living with the condition.
Understanding these impacts can help individuals and their loved ones develop strategies to manage daily life more effectively and maintain a better quality of life.
Treatment Options for Dysautonomia and Orthostatic Intolerance
Treatment options for dysautonomia depend on the underlying cause and mechanism, however, often includes lifestyle changes, medication, and therapy to manage symptoms. These treatment options aim to manage autonomic dysfunction and improve quality of life. A healthcare provider may recommend changes to diet and hydration habits to help manage blood pressure and other symptoms. Medications may be prescribed to regulate blood pressure, heart rate, and other autonomic functions.
Non-pharmacological therapy may include allied health treatment including physiotherapy, exercise physiology, or occupational therapy - however, it is important that the health professional has a good understanding of dysautonomia to ensure that any treatment is appropriate and tailored to your condition.
Lifestyle Modifications
Lifestyle modifications play a crucial role in treating dysautonomia symptoms. Depending on the underlying type of dysautonomia, this could include:
Increased fluid intake: Drinking plenty of water and electrolyte-rich beverages can help manage blood pressure and prevent dehydration.
Regular exercise and gentle reconditioning: Gentle exercises, such as yoga or swimming, can help improve cardiovascular function and reduce symptoms (assuming this is done carefully and in a way that is sensitive to symptom severity).
Avoiding triggers: Most patients benefit from identifying and avoiding triggers that exacerbate symptoms, such as postural factors, stress, heat or certain foods, can help manage dysautonomia.
Elevating the head of the bed: Raising the head of the bed by 4-6 inches can help the body to slowly adjust and adapt, helping to reduce symptoms of orthostatic hypotension over time
Avoiding heavy meals: Eating small, frequent meals can help manage blood sugar levels and reduce a sudden redirection of blood flow to the stomach, helping to prevent symptoms.
These lifestyle changes can significantly improve the quality of life for individuals with dysautonomia by helping to reduce the frequency and severity of symptoms, and promote adaptation of the autonomic nervous system over time
Research and Future Directions
Research on dysautonomia is ongoing, with a focus on developing new treatments and improving diagnosis. Ongoing research efforts are also aimed at better understanding and treating autonomic dysfunction. Future directions may include the development of new medications and therapies to manage symptoms and improve quality of life, as well as understanding the underlying causes of dysautonomia and developing new diagnostic tests.
How we can help:
At Vive, we provide integrative physiotherapy services online via video consultation. We focus on providing comprehensive assessment and tailored management plans, support, education, and resources to help you manage your condition.
We have a particular interest in treating Orthostatic Intolerance, Orthostatic Hypotension, and POTS, and understand that every person’s experience is unique. We work with patients to create personalized treatment plans that may include lifestyle modifications, trigger identification and management, flare up plans, functional goal setting, appropriate movement/exercise programs. We believe that knowledge is power. By providing up-to-date, easy-to-understand information on POTS and other forms of OI, we empower you to understand your condition and make informed decisions about your health. Whether it’s understanding the symptoms of POTS or learning how to manage flare-ups, we provide the tools and resources you need. We also work closely with your GP and other healthcare professionals, and will identify when additional referral may be required.
Check out more about how we help with POTS here
Looking for support?
We’d love to help. Check out more information on new patient assessments at https://www.vivepainfatigue.com.au/appointments
Additional Support and Resources
Living with dysautonomia can be challenging, but there are many resources available to support individuals and their families. Some good links and resources can be found here:
The Dysautonomia Project: https://thedysautonomiaproject.org/resources/
Dysautonomia International: https://www.dysautonomiainternational.org/
References
Hovaguimian, A. (2023). Dysautonomia: Diagnosis and Management. Neurologic Clinics, 41(1), 193-213.
Stewart, J. M. (2013). Common Syndromes of Orthostatic Intolerance. Pediatrics, 131(5), 968–980. https://doi.org/10.1542/peds.2012-2610
Gazit, Y., Nahir, A. M., Grahame, R., & Jacob, G. (2003). Dysautonomia in the Joint Hypermobility Syndrome. The American Journal of Medicine, 115(1), 33-40.
Zalewski, P., Słomko, J., & Zawadka-Kunikowska, M. (2018). Autonomic Dysfunction and Chronic Disease. British Medical Bulletin, 128(1), 61–74. https://doi.org/10.1093/bmb/ldy036