Application of Delphi Method-Based Definition of Treatment-Refractory Tourette Disorder in a Large Italian Clinical...

Tourette syndrome (TS) is characterized by the presence of tics and possible associated neuropsychiatric comorbidities. A subset of patients with TS present with severe and "treatment-refractory" tics, requiring multiple therapeutic interventions.

In 2023, a group of international specialist clinicians with specific expertise in tics used a multistep Delphi approach to propose an expert consensus-based definition of treatment failure for tics. In this study, we applied this recently published algorithm to establish treatment-refractory TS patients in a large Italian cohort of 614 pediatric patients.

Of the entire cohort, 20 patients (7.3%) fulfilled all the criteria proposed in this algorithm to define refractoriness to prescribed antitic medications. Compared to non-treatment-refractory (n = 254), treatment-refractory TS patients (n = 20) had significantly higher mean total intelligence quotient (P = 0.008) and mean Yale Global Tic Severity Scale-Total Tic Score scores (P < 0.00001). The 20 treatment-refractory TS patients reported a higher frequency of a family history of TS (60% vs. 46.1%), and a lower rate of associated neuropsychiatric comorbidities (55% vs. 66.9%), although these differences did not reach statistical significance.

In general, a greater tic severity might be associated with higher risk of refractoriness to pharmacological treatment for tics. Considering the paucity of literature research exploring the frequency of severe cases of TS who were refractory to medical treatment, further studies are needed to consolidate applicability within routine clinical care of this recently developed consensus definition of pharmacological treatment refractoriness for TS.