Tourette syndrome as an independent risk factor for subsequent sleep disorders in children: A nationwide population-based case-control study

Study objectives: Tourette syndrome (TS) is associated with a variety of neuropsychiatric comorbidities. However, the relationship between TS and sleep disorders in children is less investigated. This nationwide population-based case-control study aimed to determine the correlation of TS and sleep disorders in children. Methods: Patients aged less than 18 years with newly diagnosed TS from 2001 to 2007 were collected (n = 1124) using data from Taiwan's National Health Insurance Research Database and were compared with a comparison cohort (n = 3372). The adjusted hazard ratio (aHR) for developing sleep disorders was calculated by multivariate Cox proportional hazards model. Results: TS was more prevalent in boys, with a male to female ratio of 3.16:1. TS group also had significantly higher urbanization level of residence than controls (p < .001). The overall incidence rate of sleep disorders was 7.24‰ in children with TS, compared to 3.53‰ in controls. The TS group was associated with a significantly higher rate of sleep disorders, with a crude HR of 2.05 (95% confidence inerval [CI] = 1.43-2.95, p < .001). Among the comorbidities of TS, anxiety disorder was associated with the highest risk for sleep disorders (crude HR = 3.26, 95% CI = 1.52-7.00, p < .001). The aHR for TS cohort to develop sleep disorders was 1.72 (95% CI = 1.16-2.53, p = .007). Conclusions: The increased risk of sleep disorders in children with TS cannot be fully attributed to its comorbidities, and TS is an independent risk factor for sleep disorders in children.