Most surveillance colonoscopies are being booked earlier than the intervals recommended in NHMRC guidelines, a South Australian study has found.
The colonoscopy waiting list burden could be reduced and many colonoscopy complications avoided if clinicians adhered more closely to recommended scheduling intervals for surveillance, according to researchers at Adelaide University.
In an audit of 467 patients on the colonoscopy waiting list at the Queen Elizabeth Hospital, Adelaide in 2017 they found that more than half (54%) had an incorrect booking.
In a small number of cases (27) the previous colonoscopy was normal or non-neoplasia. However, for the remaining 222 patients booked incorrectly and requiring surveillance colonoscopy, 89% were booked earlier and 11% later than recommended in 2011 NHMRC guidelines.
The vast majority of incorrect bookings (86%) were a major deviation (more than 20%) from guidelines, of which 90% of deviations were early bookings.
The rate of incorrect bookings was highest for high-risk patients – such as those with large polyps that may not have been resected completely – who required 6-month surveillance interval (67% late). Almost a quarter of the 1-year colonoscopies were booked late.
Of the patients requiring five- year colonoscopy only a third (36% had a correct surveillance interval, and a high proportion (40%) were incorrectly booked for a three-year surveillance colonoscopy. Patients were more likely to be booked early if they were low risk, had a family history or past history of colorectal cancer.
The study authors said this trend “may represent an attempt by clinicians to simplify follow-up bookings for lower risk patients. Selecting a 3-year surveillance interval for these lower risk patients ensures that colonoscopy follow-up requirements are satisfied in most patients, regardless of what pathology results arise.”
The audit showed that of the 467 patients on the waiting list, 31% had a history of colonic polyps documented as the reason for their colonoscopy, 27% had a personal or family history of colorectal cancer, 22% had a positive bowel cancer screening test, 15% had GI bleeding and 3% had other GI symptoms.
“The booking of surveillance colonoscopies in accordance with the NHMRC guidelines requires attention,” the study authors concluded.
“The use of a polyp surveillance practitioner would address this problem as it removes practitioner bias. Alternatively, a computer booking program utilising algorithms based on colonoscopy and pathology findings and guideline recommendations could be developed to standardise the process of booking surveillance colonoscopies and improve guideline adherence.”
The findings are published in the Australia and NZ Journal of Surgery.