Does a Periaqueductal Gray-vagus Nerve Interface Malfunction Explain the Nat hx With Its Numerous Co-morbidities?

Postural tachycardia syndrome (POTS) is a common and disabling disorder among adolescents. No epidemiologic data exist to support the often cited 0.5 to 2% prevalence. Case series suggest 3 to 5 times greater incidence in girls than boys. POTS is defined in children as daily chronic symptoms of orthostatic intolerance and a 40 bpm rise in heart rate in the first 10 minutes of a tilt study in the absence of orthostatic hypotension. POTS often develops after an acute event like an illness, infection, immunization, head trauma, psychological trauma or surgery. Natural history data are absent for POTS, though some outcome studies exist. Orthostatic symptoms improve in the majority and heart rate changes improve in 38% at 1 year. A 2-year follow up showed small improvement in comorbid symptoms of POTS in a 12 subject cohort followed yearly. In a pediatric 5-year outcome follow up questionnaire study, 86% of adolescents with POTS reported resolved, improved, or intermittent, symptoms, with primarily physical rather than mental health complaints.