Functional tics: expanding the phenotypes of functional movement disorders? 2023 Cavanna et al

Background

Until the outbreak reported during the COVID-19 pandemic, functional tics were considered to be a relatively rare clinical phenotype, as opposed to other functional movement disorders such as functional tremor and dystonia. In order to better characterise this phenotype, we compared the demographic and clinical characteristics of patients who developed functional tics during the pandemic and those of patients with other functional movement disorders.

Methods
Data from 110 patients were collected at the same neuropsychiatry centre: 66 consecutive patients who developed functional tics without other functional motor symptoms or neurodevelopmental tics, and 44 patients with a mix of functional dystonia, tremor, gait, and myoclonus.

Results
Both groups were characterised by female sex preponderance (70-80%) and (sub)acute onset of functional symptoms (about 80%). However, patients with functional tics had a significantly earlier age at onset of functional symptoms (21 vs 39 years). Exposure to relevant social media content was reported by almost half of the patients with functional tics, but by none of the patients with other functional movement disorders. Co-morbidity profiles were similar, with relatively high rates of anxiety/affective symptoms and other functional neurological symptoms (non-epileptic attacks).

Conclusions
Patients who developed functional tics during the pandemic represent a phenotypic variant of the wider group of patients with functional movement disorders, associated with younger age at onset and influenced by pandemic-related factors, including increased exposure to specific social media content. Diagnostic protocols and treatment interventions should be tailored to address the specific features of this newly defined phenotype.

Paywall, https://onlinelibrary.wiley.com/doi/10.1111/ene.15967

 

This problem has cropped up in the media a lot.

https://www.theguardian.com/media/2...cial-media-are-developing-tourettes-like-tics

https://www.businessinsider.com/tou...edia-patients-with-tics-2021-9?op=1&r=US&IR=T

https://pubmed.ncbi.nlm.nih.gov/34558735/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8564820/

https://www.gosh.nhs.uk/conditions-and-treatments/functional-tics/