Postural orthostatic tachycardia syndrome in patients with tic disorders and functional tic-like behaviors

Postural orthostatic tachycardia syndrome (POTS) is an autonomic condition characterized by sustained excessive postural tachycardia, often accompanied by a range of other symptoms of orthostatic intolerance, including heart palpitations, light-headedness, weakness, tremulousness, blurred vision, nausea, headache, dizziness and syncope. POTS predominantly affects young females. Little is known about the exact pathophysiology of this condition; however, preliminary reports about comorbidity profile of POTS suggest a possible link with functional disorders. The striking increase in functional tic-like behaviors (a specific phenotype of functional movement disorder) during the COVID-19 pandemic offered a privileged opportunity to further explore the possible association between POTS and functional neurological disorder. In the present study, we retrospectively assessed the prevalence of POTS in two large patient populations from a specialist clinic for tic disorders: (1) patients with neurodevelopmental tics who received a diagnosis of Gilles de la Tourette syndrome (GTS), and (2) patients who developed tic-like behaviors and received a diagnosis of functional tics since the onset of the COVID-19 pandemic (April 2020 – December 2024). The prevalence of POTS was 0/638 in the GTS group and 4/177 (2.3%) in the functional tics group. The four patients with POTS were females, with age at assessment ranging from 17 to 24 years. In addition to describing their clinical characteristics, we discuss the significance of the selective association between POTS and functional tic-like behaviors, in the absence of comorbidity between POTS and neurodevelopmental tics.