title: Sex-specific prevalence of adenomas, advanced adenomas, and colorectal cancer in individuals undergoing screening colonoscopy.
abstract: BACKGROUND
  Although some studies have shown that men are at greater age-specific risk for advanced colorectal neoplasia than women, the age for referring patients to screening colonoscopy is independent of sex and usually recommended to be 50 years.
  
  
  OBJECTIVE
  To determine and compare the prevalence and number needed to screen (NNS) for adenomas, advanced adenomas (AAs), and colorectal carcinomas (CRCs) for different age groups in men and women.
  
  
  METHODS
  Cohort study of 44,350 participants in a national screening colonoscopy program over a 4-year period (2007 to 2010) in Austria.
  
  
  METHODS
  Prevalence and NNS of adenomas, AAs, and CRCs in different age groups for men and women.
  
  
  RESULTS
  The median ages were 60.7 years (interquartile range [IQR], 54.5-67.5 years) for women and 60.6 years (IQR, 54.3-67.6 years) for men, and the sex ratio was nearly identical (51.0% [22,598] vs 49.0% [21,572]). Adenomas were found in 19.7% of individuals screened (95% CI, 19.3%-20.1%; n = 8743), AAs in 6.3% (95% CI, 6.1%-6.5%; n = 2781), and CRCs in 1.1% (95% CI, 1.0%-1.2%; n = 491); NNS were 5.1 (95% CI, 5.0-5.2), 15.9 (95% CI, 15.4-16.5), and 90.9 (95% CI, 83.3-100.0), respectively. Male sex was significantly associated with a higher prevalence of adenomas (24.9% [95% CI, 24.3%-25.4%] vs 14.8% [95% CI, 14.3%-15.2%]; P < .001; unadjusted odds ratio [OR], 1.9 [95% CI, 1.8-2.0]), AAs (8.0% [95% CI, 7.6%-8.3%] vs 4.7% [95% CI, 4.4%-4.9%]; P < .001; unadjusted OR, 1.8 [95% CI, 1.6-1.9]), and CRCs (1.5% [95% CI, 1.3%-1.7%] vs 0.7% [95% CI, 0.6%-0.9%]; P < .001; unadjusted OR, 2.1 [95% CI, 1.7-2.5]). The prevalence of AAs in 50- to 54-year-old individuals was 5.0% (95% CI, 4.4%-5.6%) in men but 2.9% (95% CI, 2.5%-3.4%) in women (adjusted P = .001); the NNS in men was 20 (95% CI, 17.8-22.6) vs 34 in women (95% CI, 29.1-40; adjusted P = .001). There was no statistical significance between the prevalence and NNS of AAs in men aged 45 to 49 years compared with women aged 55 to 59 years (3.8% [95% CI, 2.3%-6.1%] vs 3.9% [95% CI, 3.3%-4.5%] and 26.1 [95% CI, 16.5-44.4] vs 26 [95% CI, 22.5-30.2]; P = .99).
  
  
  CONCLUSIONS
  Among a cohort of Austrian individuals undergoing screening colonoscopy, the prevalence and NNS of AAs were comparable between men aged 45 to 49 years and women aged 55 to 59 years.
authors.affiliation: Quality Assurance Working Group, Austrian Society for Gastroenterology and Hepatology, Vienna, Austria. monika.ferlitsch@meduniwien.ac.at
authors.forename: Monika
authors.initials: M
authors.lastname: Ferlitsch
authors.forename: Karoline
authors.initials: K
authors.lastname: Reinhart
authors.forename: Sibylle
authors.initials: S
authors.lastname: Pramhas
authors.forename: Caspar
authors.initials: C
authors.lastname: Wiener
authors.forename: Orsolya
authors.initials: O
authors.lastname: Gal
authors.forename: Christina
authors.initials: C
authors.lastname: Bannert
authors.forename: Michaela
authors.initials: M
authors.lastname: Hassler
authors.forename: Karin
authors.initials: K
authors.lastname: Kozbial
authors.forename: Daniela
authors.initials: D
authors.lastname: Dunkler
authors.forename: Michael
authors.initials: M
authors.lastname: Trauner
authors.forename: Werner
authors.initials: W
authors.lastname: Weiss
mesh_terms: D000236:Adenoma / Q000175:diagnosis* / Q000453:epidemiology* / Q000401:mortality; D001317:Austria / Q000453:epidemiology; D015331:Cohort Studies; D003113:Colonoscopy / Q000592:standards / Q000706:statistics & numerical data*; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000453:epidemiology* / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000706:statistics & numerical data*; D008875:Middle Aged; D016017:Odds Ratio; D017410:Practice Guidelines as Topic; D015995:Prevalence; D012737:Sex Factors