| Background and aimsColorectal cancer(CRC)is one of the most common malignant tumors,and its incidence and mortality are increasing.According to the global cancer statistics in 2020,CRC is newly diagnosed in more than 555,000 patients,and it is the third most common malignant tumor in China.The occurrence of colorectal cancer may be related to the patient’s age,diet and genetic factors,and the early symptoms of most patients with colorectal cancer are not typical.Of note,colorectal cancer is usually first detected during colonoscopy.Therefore,colonoscopy has been recommended by most countries to screen for precancerous lesions of CRC,aiming to reduce the incidence of colorectal cancer.Successful cecal intubation is the basis of the complete colonoscopy,and cecal intubation time(CIT)is not only an important factor to evaluate colonoscopy,but also can be used to evaluate the difficulty of colonoscopy.Previous studies found that lean patients had less abdominal fat to support the colon and have a smaller abdominal cavity size,which may result in loops formation during cecal intubation.However,previous studies are still controversial whether body mass index(BMI)is associated with CIT.Colonoscopy is a procedure based on manual operation and diagnosis,which can be affected by the endoscopist.And the endoscopist’s experience is related to cecal intubation rate(CIR),CIT and the incidence of complications.BMI and the endoscopist’s experience may correlate with cecal intubation time(CIT),but the current conclusions are controversial.Such a controversy may be related to the heterogeneity in the patients’characteristics,endoscopists’experiences,and types of colonoscopy(i.e.,sedated or unsedated)among studies.However,to the best of our knowledge,few studies have evaluated the effect of BMI on CIT at different stages of an endoscopist.Herein,we have conducted this retrospective observational study to clarify the association between BMI and CIT by one endoscopist at three different stages during unsedated colonoscopy.Methods:Consecutive 1500 patients undergoing unsedated colonoscopy by the same endoscopist at the Department of Gastroenterology of General Hospital of Northern Theater Command from December 11,2020 to August 21,2022 were reviewed.They were divided into three stages according to the number of colonoscopies performed by one endoscopist,including intermediate(501-1000 colonoscopies),experienced(1001-1500 colonoscopies),and senior stages(1501-2000 colonoscopies).The exclusion criteria were as follows:(1)endoscopic polypectomy was performed during the CI procedure;(2)cecal intubation was not completed due to colorectal occupation or unbearable pain;(3)patients had a history of colorectal resection surgery;(4)CIT data was lacking;(5)colonoscopy was not independently completed by the endoscopist;and(6)CIT was influenced by the problems of endoscopic equipment.Variables which significantly correlated with CIT were identified by Spearman’s rank correlation analyses,and then were included in a multiple linear regression analysis.Results:Overall,1233 patients were included.Among them,392,420,and 421 patients were divided into intermediate,experienced,and senior stages,respectively.The median CIT was 7.83,6.38,and 5.58 minutes at intermediate,experienced,and senior stages,respectively(P<0.001).BMI negatively correlated with CIT at the three stages(intermediate stage:r_s=-0.195,P<0.001;experienced stage:r_s=-0.252,P<0.001;senior stage:r_s=-0.257,P<0.001),and multiple linear regression analyses also demonstrated that a lower BMI predicted a longer CIT at the three stages(intermediate stage:β=-0.101,P=0.041;experienced stage:β=-0.148,P=0.002;senior stage:β=-0.134,P=0.004).Conclusion:CIT gradually decreased with the increase of endoscopists’experience.Regardless of endoscopist’s experience,there is a negative correlation between BMI and CIT.A lower BMI might be an indicator of difficult colonoscopy.Experienced endoscopists should be invited to perform colonoscopy in lean population. |
PDF Full Text Request