title: Familial occurrence of headache disorders: A population-based study in mainland China.
abstract: BACKGROUND
  Headache disorders are highly prevalent worldwide, and familial occurrence and heredity are contributory factors attracting the interest of epidemiological researchers. Our purpose, in a large sample drawn nationwide from the Chinese general population, was to evaluate the frequency of similar headache in first-degree relatives (FDRs) of those with different headache types.
  
  
  METHODS
  This was a questionnaire-based nationwide cross-sectional door-to-door survey using cluster random-sampling, selecting one adult (18-65 years) per household. Headache was diagnosed by ICHD-II criteria. Participants with headache were asked whether or not any FDRs had similar headache to their own. Chi-squared test and multivariate logistic regression analysis were used to assess the strength and significance of associations.
  
  
  RESULTS
  Of 5041 survey participants (participation rate 94.1%), 1060 (21.0%) were diagnosed with headache (migraine 469 [9.3%], tension-type headache [TTH] 543 [10.8%], headache on ≥15 days/month 48 [0.95%]). From these, 31 were excluded because of missing data about FDRs, leaving 1029 for analysis (male 350 [mean age: 46.7±11.4years]; female 679 [mean age 46.3±11.2years]). Similar headache in one or more FDRs was reported by 22.2% (95% CI: 19.6-24.7%) overall, by 25.1% (21.1-29.1%) of those with migraine, by 19.1% (15.7-22.4%) with TTH and by 29.2% (16.3-42.0%) with headache on ≥15 days/month. The differences was significant between migraine and TTH (OR=1.4, p=0.023), but were not significant between headache on ≥15 days/month and TTH (OR=1.7, p=0.093), migraine and headache on ≥15 days/month (OR=1.2,p=0.534). In multivariate analysis: for migraine versus TTH,AOR=1.2 (p=0.015); for headache on ≥15 days/month versus TTH, AOR 2.3 (p=0.018).
  
  
  CONCLUSIONS
  Headache was highly prevalent in China and common among FDRs of those with any type of headache (headache on ≥15 days/month>migraine>TTH). Against the background of the general-population prevalence of each disorder, familial occurrence was a very highly influential factor in headache on ≥15 days/month. There are important implications in this for public health and education.
authors.affiliation: Department of Neurology, Chinese PLA General Hospital, Fuxing Road 28, Haidian District, 100853 Beijing, China. Electronic address: hemianwang@hotmail.com.
authors.forename: Mianwang
authors.initials: M
authors.lastname: He
authors.affiliation: Department of Neurology, Chinese PLA General Hospital, Fuxing Road 28, Haidian District, 100853 Beijing, China. Electronic address: yusy1963@126.com.
authors.forename: Shengyuan
authors.initials: S
authors.lastname: Yu
authors.affiliation: Department of Neurology, Chinese PLA General Hospital, Fuxing Road 28, Haidian District, 100853 Beijing, China. Electronic address: liurz301@sina.com.
authors.forename: Ruozhuo
authors.initials: R
authors.lastname: Liu
authors.affiliation: Department of Neurology, Xiangya Hospital, Central-South University, Changsha, Hunan Province, China. Electronic address: sjnk_xy@yahoo.com.cn.
authors.forename: Xiaosu
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Neurology, The Fourth Military Medical University, Xian, Shaanxi Province, China. Electronic address: fmmuzhaogang@163.com.
authors.forename: Gang
authors.initials: G
authors.lastname: Zhao
authors.affiliation: Department of Neurology, Affiliated Huashan Hospital of Fudan University, Shanghai, China. Electronic address: qiaoxy@yahoo.com.
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Qiao
authors.affiliation: Department of Neurology, The First Hospital of Jilin University, Changchun, Jilin Province, China. Electronic address: fengjcfrank@yahoo.com.cn.
authors.forename: Jiachun
authors.initials: J
authors.lastname: Feng
authors.affiliation: Department of Neurology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China. Electronic address: fangyannan@21cn.com.
authors.forename: Yannan
authors.initials: Y
authors.lastname: Fang
authors.affiliation: Department of Health and Economics, Chinese PLA General Hospital, Beijing, China. Electronic address: xtcao@sina.com.
authors.forename: Xiutang
authors.initials: X
authors.lastname: Cao
authors.affiliation: Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway. Electronic address: t.steiner@imperial.ac.uk.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Steiner
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005190:Family; D005260:Female; D020022:Genetic Predisposition to Disease; D051270:Headache Disorders, Primary / Q000453:epidemiology*; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D008881:Migraine Disorders / Q000453:epidemiology*; D015995:Prevalence; D018781:Tension-Type Headache / Q000453:epidemiology*; D055815:Young Adult
keywords: China; First-degree relatives; Global campaign against headache; Headache; Heredity; Lifestyle; Population-based survey