title: Tourette syndrome and risk of depression: a population-based cohort study in Taiwan.
abstract: OBJECTIVE
  The temporal relationship between Tourette syndrome (TS) and depression is unclear. This cohort study evaluates the relationship between TS and depression in Taiwan.
  
  
  METHODS
  Claims data from the Taiwan National Health Insurance database were used to conduct retrospective cohort analyses. The study cohort contained 1337 TS patients who were frequency matched by sex, age, urbanization of residence area, parental occupation, and baseline year with 10 individuals without TS. Cox's proportional hazard regression analysis was conducted to estimate the effects of TS on depression risk.
  
  
  RESULTS
  In patients with TS, the risk of developing depression was significantly higher than in patients without TS (p value for log-rank test < .0001). After adjusting for potential confounding, the TS cohort was 4.85 times more likely to develop depression than the control cohort (HR = 4.85, 95% CI = 3.46-6.79).
  
  
  CONCLUSIONS
  In Taiwan, patients with TS have a higher risk of developing depression. The findings of this study are compatible with studies from other countries. This study could provide an evidence to inform the prognosis for a child with TS. The mechanism between TS and increased depression risk requires further investigation.
authors.affiliation: Department of Pediatrics, China Medical University Hospital, China Medical University, Taichung, Taiwan.
authors.forename: I-Ching
authors.initials: IC
authors.lastname: Chou
authors.forename: Hung-Chih
authors.initials: HC
authors.lastname: Lin
authors.forename: Che-Chen
authors.initials: CC
authors.lastname: Lin
authors.forename: Fung-Chang
authors.initials: FC
authors.lastname: Sung
authors.forename: Chia-Hung
authors.initials: CH
authors.lastname: Kao
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D002648:Child; D003863:Depression / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology; D005879:Tourette Syndrome / Q000150:complications* / Q000453:epidemiology / Q000523:psychology