title: Chronic daily headache in Korea: prevalence, clinical characteristics, medical consultation and management.
abstract: OBJECTIVE
  Chronic daily headache (CDH) is a commonly reported reason for visiting hospital neurology departments, but its prevalence, clinical characteristics, and management have not been well documented in Korea. The objective of this study was to characterize the 1-year prevalence, clinical characteristics, medical consultations, and treatment for CDH in Korea.
  
  
  METHODS
  The Korean Headache Survey (KHS) is a nationwide descriptive survey of 1507 Korean adults aged between 19 and 69 years. The KHS investigated headache characteristics, sociodemographics, and headache-related disability using a structured interview. We used the KHS data for this study.
  
  
  RESULTS
  The 1-year prevalence of CDH was 1.8% (95% confidence interval, 1.1-2.5%), and 25.7% of the subjects with CDH met the criteria for medication overuse. Two-thirds (66.7%) of CDH subjects were classified as having chronic migraine, and approximately half of the CDH subjects (48.1%) reported that their headaches either substantially or severely affected their quality of life. Less than half (40.7%) of the subjects with CDH reported having consulted a doctor for their headaches and 40.7% had not received treatment for their headaches during the previous year.
  
  
  CONCLUSIONS
  The prevalence of CDH was 1.8% and medication overuse was associated with one-quarter of CDH cases in Korea. Many subjects with CDH do not seek medical consultation and do not receive appropriate treatment for their headaches.
authors.affiliation: Department of Neurology, Uijeongbu St. Mary's Hospital, The Catholic University of Korea College of Medicine, Uijeongbu, Korea.
authors.forename: Jeong-Wook
authors.initials: JW
authors.lastname: Park
authors.affiliation: Department of Neurology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Heui-Soo
authors.initials: HS
authors.lastname: Moon
authors.affiliation: Department of Neurology, Chungnam National University College of Medicine, Daejeon, Korea.
authors.forename: Jae-Moon
authors.initials: JM
authors.lastname: Kim
authors.affiliation: Department of Neurology, Seoul St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea.
authors.forename: Kwang-Soo
authors.initials: KS
authors.lastname: Lee
authors.affiliation: Department of Neurology, Hallym University College of Medicine, Anyang, Korea.
authors.forename: Min Kyung
authors.initials: MK
authors.lastname: Chu
keywords: chronic daily headache; chronic migraine; epidemiology; headache; migraine