Factors that predict cecal insertion time during sedated colonoscopy: The role of waist circumference

Background and Aim: 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. Conclusion: 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.