Tourette's syndrome is associated with an increased risk of traumatic brain injury: A nationwide population-based cohort study

Introduction: Violent motor tics or severe self-harm behaviors have been reported in patients with Tourette's syndrome (TS) and leading to traumatic brain injury (TBI). The study aimed to determine the risk of TBI in TS patients, the effects associated with concurrent psychiatric disorders (attention-deficit/hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), or depressive disorder), and the effects of medication treatment (antipsychotics, antidepressants, or clonidine) on the risk of TBI. Methods: Using the National Health Insurance Research Database of Taiwan, 2261 TS patients and 20349 non-TS controls matched by gender and age were enrolled between 2000 and 2012, and followed until the end of 2013. Participants who developed TBI during the follow-up period were identified. Cox regression analysis was performed to examine the risk of TBI between TS patients and non-TS controls. Results: TS patients were associated with an increased risk of TBI compared to non-TS controls (hazard ratio (HR): 1.59, 95% confidence interval (95% CI): 1.37-1.85). Also, this study revealed TS patients with ADHD, OCD, or depressive disorder predicted a higher TBI incidence rate than those who did not, but the estimate was not statistically significant. Moreover, this study found that TS patients with frequent use of antipsychotics were associated with a lower risk of TBI than infrequent users (HR: 0.76, 95% CI: 0.57-0.99). Conclusions: This study highlights the need to pay more attention to the risk of TBI in TS patients, and the importance of adequate antipsychotic medication may reduce the risk of TBI.