title: Normal values for high-resolution anorectal manometry/topography in a healthy Korean population and the effects of gender and body mass index.
abstract: BACKGROUND
  High-resolution manometry (HRM) based on spatiotemporal plots is increasingly being used. The aim this study was to evaluate, for the first time, the influence of gender, with adjustment for age, body mass index (BMI), and vaginal delivery, on anorectal functions in asymptomatic adults.
  
  
  METHODS
  Fifty-four asymptomatic healthy subjects (M : F = 27 : 27; age = 20-67 years) who were matched by age and gender were enrolled prospectively. We evaluated anorectal pressures, rectal sensation using a HRM probe, and balloon expulsion time. Multivariate linear regression analysis was performed to identify the independent effects of each factor.
  
  
  RESULTS
  Anal resting pressure (median [IQR]; 32 [18] vs 46 [17] mmHg, p < 0.001), anal squeeze pressure (75 [28] vs 178 [72] mmHg, p < 0.001), rectal pressure (33 [16] vs 53 [46] mmHg, p = 0.009) and anal pressure (16 [17] vs 30 [36] mmHg, p = 0.019) during simulated evacuation with rectal distention, and the threshold for the desire to defecate (60 [20] vs 80 [60] mL, p = 0.020) were significantly lower in women than in men. BMI was positively correlated with anal resting pressure (95% CI: 0.598-2.947) and negatively correlated with the threshold for first sensation (95% CI: -0.099 to -0.015). Vaginal delivery did not affect any of the anorectal HRM parameters.
  
  
  CONCLUSIONS
  HRM parameters may be associated with gender and BMI. Therefore, gender and BMI should be taken into consideration when interpreting HRM results.
authors.affiliation: Department of Gastroenterology, Asan Digestive Disease Research Institute, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: H J
authors.initials: HJ
authors.lastname: Lee
authors.forename: K W
authors.initials: KW
authors.lastname: Jung
authors.forename: S
authors.initials: S
authors.lastname: Han
authors.forename: J W
authors.initials: JW
authors.lastname: Kim
authors.forename: S-K
authors.initials: SK
authors.lastname: Park
authors.forename: I J
authors.initials: IJ
authors.lastname: Yoon
authors.forename: H S
authors.initials: HS
authors.lastname: Koo
authors.forename: S Y
authors.initials: SY
authors.lastname: Seo
authors.forename: D-H
authors.initials: DH
authors.lastname: Yang
authors.forename: K-J
authors.initials: KJ
authors.lastname: Kim
authors.forename: B D
authors.initials: BD
authors.lastname: Ye
authors.forename: J-S
authors.initials: JS
authors.lastname: Byeon
authors.forename: S-K
authors.initials: SK
authors.lastname: Yang
authors.forename: J-H
authors.initials: JH
authors.lastname: Kim
authors.forename: S-J
authors.initials: SJ
authors.lastname: Myung
mesh_terms: D000328:Adult; D000368:Aged; D001003:Anal Canal / Q000502:physiology*; D044466:Asian People; D015992:Body Mass Index; D003672:Defecation; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D012007:Rectum / Q000502:physiology*; D012737:Sex Factors; D055815:Young Adult
keywords: Asians; body mass index; gender; high-resolution anorectal manometry; reference values