WASh multicentre randomised controlled trial: water-assisted sigmoidoscopy in English NHS bowel scope screening

Abstract

ObjectivesThe English Bowel Cancer Screening Programme invites 55 year olds for a sigmoidoscopy (Bowel Scope Screening (BSS)), aiming to resect premalignant polyps, thus reducing cancer incidence. A national patient survey indicated higher procedural pain than anticipated, potentially impacting on screening compliance and effectiveness. We aimed to assess whether water-assisted sigmoidoscopy (WAS), as opposed to standard CO2 technique, improved procedural pain and detection of adenomatous polyps.DesignThe WASh (Water-Assisted Sigmoidoscopy) trial was a multicentre, single-blind, randomised control trial for people undergoing BSS. Participants were randomised to either receive WAS or CO2 from five sites across England. The primary outcome measure was patient-reported moderate/severe pain, as assessed by patients on a standard Likert scale post procedure prior to discharge. The key secondary outcome was adenoma detection rate (ADR). The costs of each technique were also measured.Results1123 participants (50% women, mean age 55) were randomised (561 WAS, 562 CO2). We found no difference in patient-reported moderate/severe pain between WAS and CO2 (14% in WAS, 15% in CO2; p=0.47). ADR was 15% in the CO2 arm and 11% in the WAS arm (p=0.03); however, it remained above the minimum national performance standard in both arms. There was no statistical difference in mean number of adenomas nor overall polyp detection rate. There was negligible cost difference between the two techniques.ConclusionIn the context of enema-prepared unsedated screening sigmoidoscopies performed by screening-accredited endoscopists, no difference in patient-reported pain was seen when using either a CO2 or WAS intubation technique.Trial registration numberISRCTN81466870.

Water immersion sigmoidoscopy versus standard insufflation for colorectal cancer screening: A cohort study

“…Its advantages include lower cost and risk compared with colonoscopy and a more limited bowel preparation. Its disadvantages include a lower protection against right-sided colon cancer, and in case of unsedated procedures, as is usually planned in population-based screening programs,[ 1 2 3 4 5 6 24 ] a low satisfaction experience for patients, as our study confirmed.…”

“…Our observations seem to support in part the results of a recent multicenter CRC screening sigmoidoscopy trial conducted within the English Bowel Scope Screening. [ 24 ] However, in our study, we found some differences that deserve consideration. Our data show that BBPS was comparable between groups, this notwithstanding lesion detection [ Table 2 ] was higher (even if comparable) in the WIS group than in the CO 2 S group.…”

“…Tolerance of sigmoidoscopy and willingness to repeat the procedure are critical points. [ 14 24 25 26 27 ] In our quality improvement program, we assessed patients' experience with sigmoidoscopy, an important quality domain,[ 28 ] by the proxy of willingness to repeat it in the future, a comprehensive item for assessing tolerance encompassing social and examination-related issues. [ 25 ] Unfortunately, 29.6% of females were willing to repeat sigmoidoscopy only with sedation (WIS: 33.3%; Co 2 S: 27.3%).…”