J Neurol. 2022 May 14. doi: 10.1007/s00415-022-11174-z. Online ahead of print.
ABSTRACT
BACKGROUND: Dystonic tics differ from clonic tics by their slower and more sustained nature. Dystonic tics are often present in patients with Tourette syndrome (TS) and other tic-disorders. However, their phenomenology and impact on overall impairment have not been extensively studied.
MATERIALS AND METHODS: We assessed clinical history and tic duration in video-recordings from patients with TS evaluated at our movement disorders clinic. Dystonic tics were defined as those lasting ≥ 1000 ms (ms).
RESULTS: Of the total of 201 patients with TS, there were 156 with video-recordings suitable for tic duration analysis, of their tics, 57 (36.5%) of whom had dystonic motor tics, including 9 (5.7%) with dystonic phonic tics. Dystonic motor tics had a duration range between 1033 and 15,000 ms and dystonic phonic tics between 1132 and 17,766 ms. Patients with dystonic tics were older 24.4 vs. 16.5 years (P = 0.005) and had an older age at onset 12.9 vs. 7.2 years (P < 0.001), than patients without dystonic tics. The bivariate analysis showed an association between the presence of dystonic tics, greater tic severity and wider body distribution. The multivariate regression analysis showed a statistical association with older age at evaluation (P = 0.001), greater tic severity on video-recordings (P = 0.001) and co-occurrence with complex motor tics (P = 0.020). The presence of dystonic tics increased the risk for being considered for deep brain stimulation therapy, odds ratio: 15.7 (P = 0.002).
CONCLUSION: Dystonic tics, observed in about a third of patients with TS, are associated with increased severity of TS.
PMID:35567613 | DOI:10.1007/s00415-022-11174-z
