Clinical trial NCT01729416: Prospective Randomized Controlled Trial Comparing Water and Air Colonoscopy in a Community Based Setting
Official title: Prospective Randomized Controlled Trial Comparing Water Exchange Colonoscopy and Air Colonoscopy in a Community Based Setting
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Tubular Adenoma
Colon Cancer
Hyperplastic Polyp
Keywords: colon
cancer
screening
water exchange
air
method
polyp
adenoma
detection
rate
sedation
time
procedure
Lead sponsor: University of California, Davis
Sponsor class: OTHER
First posted: 2012-11-20
Enrollment: 178
Sex: ALL
Minimum age (years): 50
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: DIAGNOSTIC

Brief summary: The purpose of this study is to determine if screening colonoscopy performed on adults with the water exchange method, as opposed to the air method, will have a higher adenoma detection rate.

Detailed description: Screening colonoscopy with removal of pre-cancerous adenomas was recently shown to result in a 53% reduction in mortality from colon cancer. While this clearly validates the practice of screening colonoscopy, missed adenomas, especially in the proximal colon, defined as including cecum, ascending colon, and transverse colon, remains a concern. This was demonstrated in a study of 183 patients who underwent back-to-back colonoscopies. In this population the overall miss rate for adenomas was 24% with proximal adenomas missed more often (27%) than left colon adenomas (21%). Another study looked at 4192 patients in the SEER (Surveillance, Epidemiology, and End Results) Medicare database who developed "interval cancers", that is colon cancer in a patient who had a colonoscopy done in the previous 6-36 months. These interval cancers were predominantly in the proximal colon (Proximal 68%, Distal 19.5%, rectum 10.4%, and unspecified 2.1%). This also suggests that pre-cancerous lesions are being missed in the proximal colon. As such a method that can increase proximal adenoma detection rate would be a welcome change.

One such emerging technique which shows promise for improving adenoma detection rate is water colonoscopy. In one of the early studies employing the water method a trend towards a higher ADR in the water method group was recognized (37% vs. 26%). The observation prompted a retrospective analysis of 1178 cases of screening and surveillance colonoscopy performed by a single endoscopist at the Sacramento VAMC, which showed an overall ADR (presence of at least one adenoma) of 27% with air colonoscopy whereas that for the water method colonoscopy was 35% (p=0.007). In a subsequent combined analysis of two prospective RCT of air vs. water colonoscopy for screening and surveillance using scheduled unsedated colonoscopy \[5\] and on-demand sedation \[6\], more patients were found to have at least one diminutive adenoma in the proximal colon in the water method group than in the air group (28% vs. 14%, respectively, p=0.0298). Another quasi randomized study of screening patients performed at Phoenix VAMC using high definition equipment confirmed a significantly higher overall ADR with the water method (n=177) compared with the air method (n=191) (57% vs. 46%) (p=0.03). The odds of detecting an adenoma was 81% higher with the water method (OR 1.81; 95% CI: 1.12-2.90) and independent of age, body mass index (BMI), current smoking and alcohol use, withdrawal time \& quality of bowel preparation. In the proximal colon ADR was significantly higher in patients examined with the water method than with air method (46% vs. 35%) (p=0.03), particularly for adenomas \<10 mm in size (38% vs. 25%) (p=007). These encouraging preliminary data reflect the potential benefits of water method colonoscopy.

Our current research question is whether this benefit is seen in a community based population as opposed to the VA population which is mostly male and Caucasian.

The investigators plan to perform a prospective, randomized controlled trial comparing proximal adenoma detection rate between a water exchange colonoscopy group and an air colonoscopy group. The investigators intend to employ scheduled sedation, instead of on-demand sedation, to continue the current protocol in place at our institution.

Patients in both the study arms will undergo a split bowel preparation before colonoscopy.

Eligibility criteria: Inclusion Criteria:

* Age ≥50 years
* Individuals able to provide informed consent
* Individuals presenting for average-risk colorectal cancer screening by colonoscopy
* Individuals presenting for surveillance of adenomatous/sessile serrated colon polyps as per the US multi-society taskforce on colorectal cancer

Exclusion Criteria:

* Patients who decline to participate
* Prior partial or complete colectomy
* Patients with history of inflammatory bowel disease (ulcerative colitis or Crohn's disease)
* Patients with prior history of colorectal cancer
* Patients with history of screening colonoscopy within the past 10 years
* Patients with history of familial polyposis syndromes (Familial Adenomatous Polyposis, Lynch Syndrome)

Primary outcomes:
measure: Proximal Adenoma detection
timeFrame: Data collected when pathology is available, typically 3-10 days after the patient's procedure. Data is collected only once per patient.
Secondary outcomes:
measure: Total adenoma detection
timeFrame: Data collected when pathology is available, typically 3-10 days after the patient's procedure. Data is only collected once per patient.
measure: Sedation requirements
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length.
measure: Total procedure time
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length.
measure: Cecal intubation time
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length.
measure: Patient position change during procedure
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length.
measure: Use of colonoscope stiffener during procedure
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length.
measure: Abdominal pressure by assistant during procedure
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length.
measure: Length of colonoscope at time of cecal intubation
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length.
measure: Procedure-related pain score
timeFrame: Data collected during and post procedure after recovery from sedation, which is usually within 1 hour post procedure
measure: Reason for air insufflation, and length of colon when air insufflation started, while performing water colonoscopy
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length.
measure: Volume of water used during water colonoscopy
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length.
measure: Patient perception regarding air and water colonoscopy
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length.
measure: Advanced adenoma detection rate
timeFrame: Data collected when pathology is available, typically 3-10 days after the patient's procedure. Data is only collected once per patient
measure: Type of polypectomy (cold biopsy/cold snare/snare cautery/need for submucosal injection/need for clip placement)
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length
measure: Bowel preparation quality by Boston Bowel Prep Scale
timeFrame: This will be collected at the time of their procedure appointment which is expected to be 2 to 3 hours in length
measure: Post procedure recovery time
timeFrame: This will be collected at the time of their procedure appointment which is expected to be 2 to 3 hours in length
measure: Serrated polyp detection rate
timeFrame: This will be collected at the time of their procedure appointment which is expected to be 2 to 3 hours in length
measure: Procedure time- morning versus afternoon
timeFrame: This will be collected at the time of their procedure appointment which is expected to be 2 to 3 hours in length
measure: Body Mass Index (BMI)
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length
measure: Smoking history
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length
measure: Alcohol consumption
timeFrame: This will be collected at their procedure appointment which is expected to be 2 to 3 hours in length
Other outcomes:
Locations:
city: Elk Grove
country: United States
facility: Elk Grove PCN, University of California, Davis
state: California
Study officials:
affiliation: University of California, Davis
name: Sooraj Tejaswi, M.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Zauber AG, Winawer SJ, O'Brien MJ, Lansdorp-Vogelaar I, van Ballegooijen M, Hankey BF, Shi W, Bond JH, Schapiro M, Panish JF, Stewart ET, Waye JD. Colonoscopic polypectomy and long-term prevention of colorectal-cancer deaths. N Engl J Med. 2012 Feb 23;366(8):687-96. doi: 10.1056/NEJMoa1100370.
citation: Rex DK, Cutler CS, Lemmel GT, Rahmani EY, Clark DW, Helper DJ, Lehman GA, Mark DG. Colonoscopic miss rates of adenomas determined by back-to-back colonoscopies. Gastroenterology. 1997 Jan;112(1):24-8. doi: 10.1016/s0016-5085(97)70214-2.
citation: Leung FW, Aharonian HS, Leung JW, Guth PH, Jackson G. Impact of a novel water method on scheduled unsedated colonoscopy in U.S. veterans. Gastrointest Endosc. 2009 Mar;69(3 Pt 1):546-50. doi: 10.1016/j.gie.2008.08.014.
citation: Leung JW, Do LD, Siao-Salera RM, Ngo C, Parikh DA, Mann SK, Leung FW. Retrospective analysis showing the water method increased adenoma detection rate - a hypothesis generating observation. J Interv Gastroenterol. 2011 Jan;1(1):3-7. doi: 10.4161/jig.1.1.14585.
citation: Leung FW, Harker JO, Jackson G, Okamoto KE, Behbahani OM, Jamgotchian NJ, Aharonian HS, Guth PH, Mann SK, Leung JW. A proof-of-principle, prospective, randomized, controlled trial demonstrating improved outcomes in scheduled unsedated colonoscopy by the water method. Gastrointest Endosc. 2010 Oct;72(4):693-700. doi: 10.1016/j.gie.2010.05.020. Epub 2010 Jul 8.
citation: Leung J, Mann S, Siao-Salera R, Ransibrahmanakul K, Lim B, Canete W, Samson L, Gutierrez R, Leung FW. A randomized, controlled trial to confirm the beneficial effects of the water method on U.S. veterans undergoing colonoscopy with the option of on-demand sedation. Gastrointest Endosc. 2011 Jan;73(1):103-10. doi: 10.1016/j.gie.2010.09.020.
citation: Leung FW, Leung JW, Siao-Salera RM, Mann SK. The water method significantly enhances proximal diminutive adenoma detection rate in unsedated patients. J Interv Gastroenterol. 2011 Jan;1(1):8-13. doi: 10.4161/jig.1.1.14587.
citation: Ramirez FC, Leung FW. A head-to-head comparison of the water vs. air method in patients undergoing screening colonoscopy. J Interv Gastroenterol. 2011 Jul;1(3):130-135. doi: 10.4161/jig.1.3.18512. Epub 2011 Jul 1.
citation: Lai EJ, Calderwood AH, Doros G, Fix OK, Jacobson BC. The Boston bowel preparation scale: a valid and reliable instrument for colonoscopy-oriented research. Gastrointest Endosc. 2009 Mar;69(3 Pt 2):620-5. doi: 10.1016/j.gie.2008.05.057. Epub 2009 Jan 10.