Ehlers-Danlos Syndromes (EDS) and Postural Orthostatic Tachycardia Syndrome (POTS) are chronic health conditions that often co-occur, leading to complex challenges. Understanding each condition and their intricate connection is helpful for those navigating these diagnoses.
Understanding Ehlers-Danlos Syndromes (EDS)
Ehlers-Danlos Syndromes (EDS) are inherited disorders affecting the body’s connective tissues, which provide support and structure to skin, bones, blood vessels, and organs. Genetic changes impair the body’s ability to produce or process collagen, a fibrous protein vital for connective tissue strength and elasticity. This leads to fragile, less supportive connective tissues throughout the body.
There are 13 recognized types of EDS, each with unique features and genetic causes. Among these, hypermobile EDS (hEDS) is the most common type and is frequently observed alongside Postural Orthostatic Tachycardia Syndrome. Primary characteristics include generalized joint hypermobility, where joints can move beyond their normal range, often leading to instability, frequent dislocations, and chronic pain. Affected individuals also experience fragile tissues, manifesting as stretchy skin that bruises easily, poor wound healing, and atrophic scars.
Understanding Postural Orthostatic Tachycardia Syndrome (POTS)
Postural Orthostatic Tachycardia Syndrome (POTS) is a disorder impacting the autonomic nervous system, which controls involuntary bodily functions like heart rate, blood pressure, digestion, and body temperature regulation. POTS is primarily characterized by an abnormal increase in heart rate that occurs upon standing. In adults, this increase is typically 30 beats per minute or more within 10 minutes of standing, or a heart rate exceeding 120 beats per minute, without a significant drop in blood pressure. For adolescents, the heart rate increase threshold is at least 40 beats per minute.
When a person stands up, gravity naturally pulls blood downwards into the lower body. In individuals without POTS, the autonomic nervous system responds by constricting blood vessels and slightly increasing heart rate to ensure adequate blood flow to the brain. However, in POTS, this automatic adjustment is impaired, meaning blood vessels may not efficiently constrict, leading to blood pooling in the legs. To compensate for the reduced blood return to the heart and brain, the heart beats much faster, resulting in the rapid heart rate characteristic of the syndrome.
Common symptoms of POTS often worsen when upright and tend to improve when lying down. These symptoms can include dizziness, lightheadedness, profound fatigue, and difficulty concentrating or “brain fog”. Other manifestations may involve heart palpitations, chest pain, shortness of breath, nausea, and sometimes a purplish discoloration of the hands and feet.
The Interconnection of EDS and POTS
Ehlers-Danlos Syndromes and Postural Orthostatic Tachycardia Syndrome frequently co-occur, presenting a complex clinical picture for many individuals. Approximately 31% of individuals diagnosed with POTS also meet the diagnostic criteria for hypermobile EDS (hEDS), indicating a notable overlap between the two conditions and suggesting shared underlying physiological mechanisms.
A primary connection lies in the faulty connective tissue associated with EDS. The laxity and fragility of connective tissues in EDS can extend to blood vessels and surrounding supporting structures throughout the body. This can lead to blood vessels that are more elastic and less able to constrict effectively, causing blood to pool in the lower extremities when an individual stands upright. When blood pools in the lower body, less blood returns to the heart and, subsequently, to the brain.
The body attempts to compensate for this reduced blood flow to the brain by increasing heart rate, which is a hallmark symptom of POTS. Furthermore, the connective tissue abnormalities in EDS may directly affect the autonomic nervous system’s ability to regulate blood vessel tone and heart rate properly. This autonomic dysfunction contributes to the symptoms experienced in POTS. Therefore, the structural issues present in EDS can predispose an individual to the circulatory and autonomic challenges seen in POTS.
Diagnosis and Living with EDS and POTS
Diagnosing Ehlers-Danlos Syndromes and Postural Orthostatic Tachycardia Syndrome involves distinct but sometimes complementary approaches. For EDS, diagnosis typically relies on a clinical evaluation, which includes assessing the degree of joint hypermobility. For hypermobile EDS, the Beighton Score is a common tool used to quantify joint flexibility. In certain types of EDS, genetic testing may be performed to confirm the specific genetic mutation responsible for the condition.
POTS diagnosis often involves tests that assess the body’s response to upright posture. A tilt-table test is frequently used, where a person lies on a table that is then tilted to an upright position while heart rate and blood pressure are continuously monitored. An active stand test, performed at the bedside, can also provide similar information about heart rate and blood pressure changes upon standing. Other tests may be conducted to rule out other conditions that could mimic POTS symptoms, such as thyroid disorders or anemia.
There is currently no cure for either EDS or POTS, so management focuses on alleviating symptoms and enhancing the individual’s quality of life. Lifestyle modifications play a significant role in managing both conditions. For POTS, increasing fluid and salt intake can help expand blood volume, which can reduce symptoms of orthostatic intolerance. Wearing compression garments, particularly on the lower extremities, can also help reduce blood pooling when upright.
Regular, gentle exercise is often recommended, though it needs to be carefully tailored to avoid exacerbating symptoms or causing joint injury in individuals with EDS. Low-impact activities such as swimming, rowing, or using a recumbent exercise bike are often preferred. Pacing activities throughout the day and incorporating rest periods are also important strategies to manage fatigue and prevent symptom flare-ups. Given the varied and complex symptoms, a multidisciplinary care team is often beneficial, including specialists such as cardiologists, neurologists, rheumatologists, and physical therapists, to provide comprehensive and individualized support.