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Advanced Neurology POTS with tics versus tic-like behaviors

1. Introduction in most cases. This condition may be precipitated by
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immunological stressors such as a viral infection (typically
1.1. Postural orthostatic tachycardia syndrome upper respiratory or gastrointestinal), vaccination,
(POTS) physical trauma (e.g., concussion), pregnancy, menarche,
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POTS is a disorder of the autonomic nervous system surgery or psychosocial stress. Exacerbating factors
characterized by sustained excessive postural tachycardia include heat, exercise, and the postprandial state, and
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(an increase of ≥30 beats/min in adults or ≥40 beats/ the perimenstrual period. Two different developmental
min in adolescents within 10 min of standing or >60° patterns have been identified: (1) acute onset after one
head-up tilt). The increased heart rate is accompanied of the abovementioned triggers or (2) slowly progressive
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by multiple symptoms of orthostatic intolerance while symptoms over prolonged periods of time. 1
standing, including heart palpitations, light-headedness, With regard to the etiology of primary POTS,
tremulousness, blurred vision, nausea, headache, two main theories have been proposed: “partial
dizziness, and syncope. Orthostatic symptoms improve dysautonomia” of neuropathic origin, possibly due to
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shortly after return to a supine position and occur in inadequate peripheral and splanchnic vasoconstriction
the absence of orthostatic hypotension (a decrease in with orthostatic stress, and “hyperadrenergic state,”
blood pressure >20/10 mmHg with postural change). characterized by hyperactivity of norepinephrine
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In addition, patients with POTS may experience other pathways, possibly due to increased norepinephrine
persistent symptoms, such as non-specific generalized production and synaptic release, and/or reduction in
weakness, neurologic conditions (migraine, cognitive norepinephrine re-uptake. A third hypothesis was
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impairment often referred to as “brain fog,” difficulty formulated as sympathetic denervation resulting in
with concentration), dyspnea, fatigue, fibromyalgia, chest central hypovolemia and reflex tachycardia. The
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pain, gastrointestinal disturbances (unspecified vomiting, influence of the autonomic nervous system on the
diarrhea, irritable bowel disease), exercise intolerance, development of POTS has gained prominence and
sleep disorders (insomnia, sleep apnea, hypersomnia), extensive research focuses on alterations in the fight-
genitourinary complaints (metrorrhagia, menorrhagia, or-flight reaction in subjects presenting with this
dysmenorrhea, incontinence, dysuria) and psychiatric condition. Autonomic dysfunction, of which POTS is
disorders (anxiety, depression, tic disorders and an important subset, has been noted in more than half
psychogenic non-epileptic seizures). POTS has been of the patients diagnosed with COVID-19 as part of
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reported in the context of autoimmune and connective their post-acute sequelae. Specifically, POTS symptoms
tissue diseases, such as Ehlers Danlos syndrome, have been included among the top three most impactful
Raynaud’s phenomenon, Hashimoto’s thyroiditis, post-acute sequelae of COVID-19 according to the
rheumatoid arthritis, and celiac disease. 5 physician notes from the patient’s initial visit. The
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Although a heterogenous clinical sample can be pathophysiology of SARS-COV-2 is thought to involve
referred to specialist assessments for POTS, this is not the virus- or immune-mediated damage to the autonomic
only group of people who experience these symptoms. It nervous system, due to autoantibody production against
has been estimated that 0.2 – 1.0% of the United States autonomic nerve fibers and/or sympathetic nervous
population is affected by POTS, which is equivalent to system stimulation secondary to infection. POTS has
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roughly 1 – 3 million people, with substantial loss of emerged as a relatively common manifestation of the
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productivity and healthcare costs. This heterogeneous long-COVID umbrella, affecting between 2% and 14%
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clinical syndrome affects younger individuals (on of survivors. Post-acute sequelae at any age comprise
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average 15 – 45 years old), particularly in Caucasian a plethora of unspecific symptoms reported later than
populations, with a significant female predominance (up 4 weeks after a confirmed or probable infection with
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to 80%). The connection with female sex remains poorly SARS-CoV-2: the most common symptoms are fatigue
understood, although one potential link is the increased and post-exertional malaise, which can present in
susceptibility to autoimmunity. A further possible association with POTS. Relatively little is known about
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explanation is the recognized association between the long-term prognosis of POTS, but it appears that
female hormones, especially estrogens, and alterations about half of the patients spontaneously recover within 1
in vascular function and blood volume. About 10% of – 3 years. After diagnostic confirmation, patients should
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subjects have a family history of orthostatic intolerance be thoroughly educated about non-pharmacological
or tachycardia, underlining the genetic underpinnings measures alleviating symptoms, such as graded exercise
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of POTS, although a monogenic cause is unlikely. and increased fluid and salt intake. The biopsychosocial
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3,4
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The age at onset of POTS is between 15 and 25 years model provides useful insights into the development of
Volume 4 Issue 2 (2025) 101 doi: 10.36922/an.8525