title: Factors that predict cecal insertion time during sedated colonoscopy: the role of waist circumference.
abstract: OBJECTIVE
  Various factors have been closely linked to the cecal insertion time. These factors include age, sex, body mass index, quality of bowel preparation, doctor's technique, a history of prior hysterectomy, diverticulosis, and constipation. Waist circumference is better than body mass index in assessing abdominal obesity and therefore may be better than body mass index in predicting cecal insertion time. The aim of this study was to evaluate the factors influencing cecal insertion time and the impact of waist circumference.
  
  
  METHODS
  This prospective study was conducted between August 2004 and June 2005 in Buddhist Dalin Tzu Chi General Hospital. Asymptomatic patients admitted to our physical check-up department were enrolled. A single endoscopist performed all colonoscopies under sedation with a single-handed method. Age, sex, body mass index, waist circumference, history of hysterectomy, constipation, bowel cleansing status, and diverticulosis were analyzed.
  
  
  RESULTS
  A total of 1022 patients were enrolled. Among them, 996 (97.5%) completed the colonoscopic examinations (472 men and 524 women). The mean +/- SD insertion time was 307 +/- 166 s for men and 403 +/- 195 s for women (P < 0.01). Female sex, poor bowel preparation, smaller waist circumference, lower body mass index and older age were associated with longer insertion time. Waist circumference was better than body mass index in predicting cecal insertion time.
  
  
  CONCLUSIONS
  Female sex, poor bowel preparation, smaller waist circumference, lower body mass index and older age were associated with a longer insertion time. Waist circumference was a better predictor than body mass index in assessing cecal insertion time.
authors.affiliation: Division of Gastroenterology, Department of Medicine, Buddhist Dalin Tzu Chi General Hospital, Chia-Yi, Taiwan.
authors.forename: Yu-Hsi
authors.initials: YH
authors.lastname: Hsieh
authors.forename: Chin-Sung
authors.initials: CS
authors.lastname: Kuo
authors.forename: Kuo-Chih
authors.initials: KC
authors.lastname: Tseng
authors.forename: Hwai-Jeng
authors.initials: HJ
authors.lastname: Lin
mesh_terms: D000005:Abdomen / Q000033:anatomy & histology*; D000367:Age Factors; D000886:Anthropometry; D015992:Body Mass Index; D002432:Cecum; D003113:Colonoscopy / Q000379:methods*; D016292:Procedural Sedation; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012737:Sex Factors; D013997:Time Factors