title: Family history and risk of hair loss.
abstract: BACKGROUND
  The genetic basis of androgenetic alopecia (AGA) is well accepted in the medical community and among the general population. However, rigorous studies investigating the familial basis of AGA are lacking. The purpose of the current study was to explore the relationship between family history and expression of AGA in a sample of men from the general community.
  
  
  METHODS
  Hair loss was assessed by an independent observer trained by an expert dermatologist using the Norwood/Hamilton classification scale and a 7-point global description of hair loss. Men were classified into two groups, one as having little or no hair loss and the other having hair loss. The family history of hair loss in parents and grandparents was assessed by subject self-report.
  
  
  RESULTS
  Adjusting for age, men whose fathers had hair loss were 2.5 times as likely to have had some level of hair loss compared to men whose fathers had no hair loss (95% CI: 1.3-4.9). Likewise, men whose fathers had hair loss were twice as likely to have hair loss than men whose fathers had no hair loss even after adjusting for age (OR = 2.1, 95% CI: 1.2-3.7 and OR = 2.5, 95% CI: 1.4-4.7 for Norwood/Hamilton and global description of hair loss assessments, respectively).
  
  
  CONCLUSIONS
  Results suggest that the probability of male pattern hair loss is dependent on family history and age. Hair loss in a man's father also appears to play an important role in increasing a man's risk of hair loss, either in conjunction with a history of hair loss in the mother or hair loss in the maternal grandfather.
authors.affiliation: Department of Community Health, Wright State University School of Medicine, Dayton, Ohio, USA.
authors.forename: W Cameron
authors.initials: WC
authors.lastname: Chumlea
authors.forename: Thomas
authors.initials: T
authors.lastname: Rhodes
authors.forename: Cynthia J
authors.initials: CJ
authors.lastname: Girman
authors.forename: Amy
authors.initials: A
authors.lastname: Johnson-Levonas
authors.forename: Flavius R W
authors.initials: FR
authors.lastname: Lilly
authors.forename: Ruishan
authors.initials: R
authors.lastname: Wu
authors.forename: Shumei S
authors.initials: SS
authors.lastname: Guo
mesh_terms: D000293:Adolescent; D000328:Adult; D000505:Alopecia / Q000453:epidemiology* / Q000209:etiology / Q000235:genetics* / Q000473:pathology; D005190:Family; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D009820:Ohio / Q000453:epidemiology; D011795:Surveys and Questionnaires; D044465:White People / Q000235:genetics