Not to be confused with Pott disease . Condition in which a change from lying to standing causes an abnormally large increase in heart rate Postural orthostatic tachycardia syndrome Other names Postural tachycardia syndrome (POTS) Specialty Cardiology , Neurology Symptoms More often with standing: lightheadedness , trouble thinking , tachycardia , weakness, [1] palpitations , heat intolerance , acrocyanosis Usual onset Most common (modal) age of onset is 14 years [2] Duration > 6 months [3] Causes Antibodies against the Alpha 1 adrenergic receptor [4] [5] [6] Risk factors Family history [1] Diagnostic method An increase in heart rate by 30 beats/min with standing [1] Differential diagnosis Dehydration , heart problems, adrenal insufficiency , epilepsy , parkinson disease [7] Treatment Avoiding factors that bring on symptoms, increasing dietary salt and water, compression stockings , exercise, medications [1] Medication Beta blockers , Ivabradine , midodrine , and fludrocortisone . [1] Prognosis ~90% improve with treatment, [8] 25% of patients unable to work [9] Frequency ~ 500,000 (US) [7] Postural orthostatic tachycardia syndrome ( POTS ) is a condition in which a change from lying to standing causes an abnormally large (or higher than normal) increase in heart beat rate . [1] This occurs with symptoms that may include lightheadedness , trouble thinking, blurred vision , or weakness. [1] Other commonly associated conditions include Ehlers–Danlos syndrome , mast cell activation syndrome , irritable bowel syndrome , insomnia , chronic headaches , chronic fatigue syndrome , and fibromyalgia . [1] Contents 1 Causation 2 Signs and symptoms 2.1 Brain fog 3 Causes 3.1 Autoimmunity 3.2 Secondary 4 COVID-19 5 Diagnosis 5.1 Diagnostic criteria 5.2 Autoantibodies against G-protein coupled receptor 5.3 Orthostatic intolerance 5.4 Differential diagnoses 6 Treatment 6.1 Medication 7 Prognosis 8 Epidemiology 9 History 10 Notable cases 11 References 12 Further reading 13 External links Causation [ edit ] The causes of POTS are varied. [10] Often, it begins after a viral infection, surgery, or pregnancy. [8] Risk factors include a family history of the condition. [1] Diagnosis in adults is based on an increase in heart rate of more than 30 beats per minute within ten minutes of standing up that is accompanied by symptoms. [1] Low blood pressure with standing , however, does not occur. [1] Other conditions which can cause similar symptoms, such as dehydration , heart problems, adrenal insufficiency , epilepsy , and parkinson disease , must not be present. [7] Treatment may include avoiding factors that bring on symptoms, increasing dietary salt and water, small and frequent meals, [11] avoidance of immobilization, [11] compression stockings , exercise program, and medications. [12] [13] [1] [14] Medications used may include beta blockers , [15] pyridostigmine , [16] midodrine [17] or fludrocortisone . [1] More than 50% of people whose condition was triggered by a viral infection get better within five years. [8] About 80% have symptomatic improvement with treatment, but 25 percent of patients are still unable to work. [9] [8] Retrospective studies has shown that five years after diagnosis 19% had a full resolution of symptom. [18] It is estimated that 500,000 people are affected in the United States. [19] The average age of onset is 20 years old, and it occurs about five times more frequently in females. [1] Signs and symptoms [ edit ] In adults the primary symptom is an increase in heart rate of more than 30 beats per minute within ten minutes of standing up. [1] [20] The resulting heart rate is typically more than 120 beats per minute. [1] For people aged between 12 and 19, the minimum increase for diagnosis is 40 beats per minute. [21] This symptom is known as orthostatic (upright) tachycardia (fast heart rate). It occurs without any coinciding drop in blood pressure, as that would indicate orthostatic hypotension . [20] Certain medications to treat POTS may cause orthostatic hypotension. It is accompanied by other features of orthostatic intolerance —symptoms that develop in an upright position and are relieved by reclining. [20] These orthostatic symptoms include palpitations , light-headedness , chest discomfort, shortness of breath , [20] nausea, weakness or "heaviness" in the lower legs, blurred vision , and cognitive difficulties. [1] Symptoms may be exacerbated with prolonged sitting, prolonged standing, alcohol, heat, exercise, or eating a large meal. [ citation needed ] In up to one third of people with POTS, [1] fainting occurs in response to postural changes or exercise. [22] Migraine -like headaches are common, sometimes with symptoms worsening in an upright position ( orthostatic headache ). [22] 40-50% of patients with POTS develop acrocyanosis of extremities, a reddish-purple color in the legs and/or hands when they stand (indicative of blood pooling). [23] [22] [24] 48% of people with POTS report chronic fatigue and 32% report sleep disturbances . [25] [26] [27] [28] Others exhibit only the cardinal symptom of orthostatic tachycardia. [22] Additional symptoms are varied, and may include excessive sweating, a lack of sweating, heat intolerance, digestive issues such as bloating, nausea, indigestion, constipation, and diarrhea, a flu-like feeling, coat-hanger pain, forgetfulness, brain fog, and presyncope . [29] Brain fog [ edit ] One of the most disabling and prevalent symptoms in POTS is " brain fog ", [30] a term used by patient to describe the cognitive difficulties they experience. In one survey of 138 POTS patients, brain fog was defined as “forgetful” (91%), “difficulty thinking” (89%), and “difficulty focusing” (88%). Other common description was "Difficulty processing what others say" (80%), Confusion (71%), Lost (64 %), and "Thoughts moving too quickly" (40%) [31] The same survey described the most common triggers of brain fog to be fatigue (91%), lack of sleep (90%), prolonged standing (87%) and dehydration (86%). [ citation needed ] Neuropsychological testing has shown that a POTS-patient has reduced attention (Ruff 2&7 speed and WAIS-III digits forward), short-term memory ( WAIS-III digits back), cognitive processing speed ( Symbol digits modalities test ) and executive function ( Stroop word color and trails B ). [32] [33] [34] A potential cause for brain fog is a decrease in cerebral blood flow (CBF), especially in upright position. [35] [36] [37] Another theory is that interoception of excessive autonomic activity causes interoceptive prediction errors (PE) to occur. [38] A prediction error is the mismatch between a prior expectation and reality. [39] This would cause anxiety which then overwhelms the consciousness of pots-patient causing cognitive-affective symptoms.
