Psychiatric comorbidity in functional tics: a scoping review.

BACKGROUND

There has been a dramatic rise in the prevalence of functional tics since the COVID-19 pandemic. While the prevalence of various comorbidities has been well defined in primary tic disorders such as Tourette Syndrome, less is known about this topic in patients with functional tics. Therefore, the purpose of this scoping review is to characterize what is known about the prevalence of psychiatric and neurologic comorbidities in patients with functional tics and identify gaps that persist in this literature.

METHODS

A comprehensive search across multiple databases was used for data collection. We included studies that provided original data on the presence of psychiatric comorbidities in patients with a diagnosis of functional tics. Study screening progress was documented in a Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow chart. A total of 150 titles and abstracts were screened, 78 full texts were evaluated for eligibility, and 31 studies were included.

RESULTS

The included studies identified epidemiological data and common psychiatric and neurologic comorbidities in patients with functional tics. Most of the studies reviewed were published after 2020, highlighting the recent uptick in incidence and prevalence of functional tics. Depression and anxiety, followed by attention deficit hyperactivity disorder and obsessive-compulsive disorder, were among the most commonly identified comorbidities.

CONCLUSIONS

Overall, further research on the prevalence of comorbidities in patients with functional tics is needed to inform clinicians’ differential diagnosis and integrated treatment planning. Depression and anxiety are common comorbidities in patients with functional tics and may be underrecognized and underreported. The prevalence of all comorbidities appears to have increased since the COVID-19 pandemic. Future research should further quantitatively define the comorbidity profile in functional tics. CLINICAL TRIAL NUMBER: Not applicable.