title: Cluster headache is associated with an increased risk of depression: a nationwide population-based cohort study.
abstract: OBJECTIVE
  To investigate whether cluster headache (CH) was a risk factor for depression in a nationwide population-based follow-up study. Background There are few studies about the relationship between CH and depression, and prior research has been limited by cross-sectional studies or small sample sizes.
  
  
  METHODS
  We identified 673 CH patients from the Taiwan National Health Insurance database between 2005 and 2009. The two comparison cohorts included age-, sex- and Charlson's score-matched migraine patients (n = 2692) and controls (patients free from migraine or CH, n = 2692). The cumulative incidence of depression was compared among these three cohorts until the end of 2009. We also calculated predictors of depression in the CH cohort.
  
  
  RESULTS
  After the median 2.5-year follow-up duration, the CH cohort had a greater risk for developing depression compared to the control cohort (adjusted hazard ratio; aHR = 5.6, 95% CI 3.0-10.6, p < 0.001) but not the migraine cohort (aHR = 1.1, 95% CI 0.7-1.7, p = 0.77). Of the CH patients, the number of cluster bout periods per year was a risk factor for depression (aHR = 3.8, 95% CI 2.6-5.4, p < 0.001).
  
  
  CONCLUSIONS
  Our results showed that CH is associated with an increased risk for depression. The strength of this association is similar to that of migraine.
authors.affiliation: Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taiwan.
authors.forename: Jen-Feng
authors.initials: JF
authors.lastname: Liang
authors.forename: Yung-Tai
authors.initials: YT
authors.lastname: Chen
authors.forename: Jong-Ling
authors.initials: JL
authors.lastname: Fuh
authors.forename: Szu-Yuan
authors.initials: SY
authors.lastname: Li
authors.forename: Chia-Jen
authors.initials: CJ
authors.lastname: Liu
authors.forename: Tzeng-Ji
authors.initials: TJ
authors.lastname: Chen
authors.forename: Chao-Hsiun
authors.initials: CH
authors.lastname: Tang
authors.forename: Shuu-Jiun
authors.initials: SJ
authors.lastname: Wang
mesh_terms: D000328:Adult; D015984:Causality; D003027:Cluster Headache / Q000453:epidemiology*; D015331:Cohort Studies; D003863:Depression / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology