Introduction

This article is meant to disseminate recent scientific progress on Gilles de la Tourette Syndrome (GTS), summarizing research reports the authors judged important or interesting. 

Methods

We searched PubMed using the search strategy ("Tic Disorders"[MeSH] OR Tourette NOT Tourette[AU] NOT Tourette[COIS]) AND 2022[PDAT] NOT 1950:2021[PDAT]. On 09 Jan 2023 this search returned 216 citations, available at this link. Colleagues also recommended articles, and we attended selected medical conferences. We selected material for this review subjectively, guided by our judgment of possible future impact on the field.

Results

Phenomenology and natural history

Definition

On blinded video review, the frequency of "extra" (non-goal-directed) movements was more than three times higher in patients with a tic disorder than in people without a tic disorder,  vocalizations were > 22 times more frequent, and obsessive-compulsive and depressive symptoms were much more common. However, the occurrence and frequency of "extra" movements overlapped between those with and without a tic disorder: therefore, the authors concluded that surplus movements per se are not sufficient to diagnose tics. The repetitive character, timing pattern, and associated features of tics such as premonitory urges are necessary too. These results will not surprise tic clinicians, but highlight difficulties in attempting  to diagnose and count tics by artificial intelligence analysis of video data \citep{Bartha2023}.

Epidemiology

A study from the U. S. Centers for Disease Control and Prevention (CDC) attempted to synthesize the varied data on prevalence of persistent (chronic) tic disorders in the US \citep{35724469}. They estimate that 350,000–400,000 children and adults have Tourette syndrome, and about a million more have motor or vocal persistent tic disorder, but they conclude that new data with more accurate methods is required to be more confident in the results.

Prognosis and natural history

Ricketts and colleagues evaluated childhood predictors of adult tic severity and impairment and found that childhood severity of tics and female sex are important predictors for tic severity and impairment in adulthood \citep{36229120}