title: Increased risk of adenomas in individuals with a family history of colorectal cancer: results of a meta-analysis.
abstract: OBJECTIVE
  It is unclear to what extent the increased risk of colorectal cancer in individuals with a family history of colorectal cancer and no known genetic disorders is associated with a higher adenoma prevalence. Our aim is to estimate the relative difference in adenoma prevalence and its age-pattern in individuals with a family history of colorectal cancer compared to those without.
  
  
  METHODS
  We performed a literature search to identify colonoscopy studies reporting the adenoma prevalence by age. Using multilevel logistic regression, we examined how the adenoma prevalence by age differed between individuals with and without a family history of colorectal cancer. We excluded members of families with a known genetic disorder.
  
  
  RESULTS
  Thirteen colonoscopy studies were identified. The adenoma prevalence was significantly higher in individuals with a family history than in those without (OR 1.7, 95% CI 1.4-3.5). The adenoma prevalence increased with age (OR per year of age 1.06, 95% CI 1.05-1.07). The age trend did not differ significantly between the two groups.
  
  
  CONCLUSIONS
  Individuals with a family history of colorectal cancer have a considerably higher prevalence of adenomas compared to individuals without a family history. This is consistent with their increased risk of colorectal cancer.
authors.affiliation: Department of Public Health, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, The Netherlands. j.wilschut@erasmusmc.nl
authors.forename: Janneke A
authors.initials: JA
authors.lastname: Wilschut
authors.forename: J Dik F
authors.initials: JD
authors.lastname: Habbema
authors.forename: Scott D
authors.initials: SD
authors.lastname: Ramsey
authors.forename: Rob
authors.initials: R
authors.lastname: Boer
authors.forename: Caspar W N
authors.initials: CW
authors.lastname: Looman
authors.forename: Marjolein
authors.initials: M
authors.lastname: van Ballegooijen
mesh_terms: D000236:Adenoma / Q000453:epidemiology / Q000209:etiology*; D000328:Adult; D000465:Algorithms; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000209:etiology*; D004198:Disease Susceptibility / Q000453:epidemiology; D005192:Family Health; D005260:Female; D006801:Humans; D008297:Male; D008487:Medical History Taking; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors