Quality indicators of endoscopists for both index and surveillance colonoscopy are associated with risk of Metachronous Colorectal Neoplasia.

[BACKGROUND] An association between higher adenoma detection rate (ADR) at index screening colonoscopy and lower risk of metachronous advanced neoplasia (AN, defined as colorectal cancer (CRC) or advanced adenoma (AA)) has been reported. However, the relationship between ADR at both index and surveillance colonoscopy and subsequent AN is unknown. We examined the association between ADR and withdrawal time (WT) at index and surveillance colonoscopy and risk of metachronous AN at surveillance colonoscopy.

[METHODS] We used GIQuIC, a repository of colonoscopies across the US. Each patient has a unique ID at a participating site. Endoscopist NPI are associated with each exam. We included patients with two colonoscopies at least 3 years apart (index and surveillance) between 2011 and 2022 and calculated the ADR and average WT for the endoscopist performing the index and surveillance colonoscopies respectively. We built a multivariable logistic regression model with metachronous AN as the outcome and ADR and WT as independent variables, controlling for patient age, sex and race.

[RESULTS] We included 768,274 patients and 3,425 endoscopists. Mean patient age was 61 years and 48% were male; 66% were White and 3% were Hispanic. Indication for index colonoscopy were screening (43.4%), surveillance (39.0%) and diagnostic (17.6%). ADR quartiles were ≤29.7%, >29.7%-37.2%, >37.2%-45.0% and >45%. WT quartiles were ≤7.1 min, >7.1 -8.2 min, >8.2-9.7min, >9.7min. Advanced neoplasia detection was lowest when low ADR endoscopists performed both index and surveillance exams (5.4%, Table 1) and high ADR index exams were followed by low ADR surveillance exams (4.0%). Compared to low ADR endoscopists for both index and surveillance exams, advanced was significantly higher when both exams performed by a high ADR endoscopist (AA 7.4%; OR for AN 1.10(1.05-1.16)) or low ADR index exams were followed by high ADR surveillance exams (AA 13.3%; OR for AN 1.448 (1.37-1.51)). Compared to short WT endoscopists for both exams (AA 7.2%; CRC 0.3%), advanced neoplasia detection was higher when both exams were performed by a long WT endoscopist or short WT index exams were followed by long WT surveillance exams (AA 7.0% p=.53 and 9.9%, P<0.001) but similar CRC detection of 0.2% and 0.2% (p 0.14). Other factors associated with finding of metachronous advanced neoplasia were older age (>=76 years vs 45-55 years OR 1.64; 95% CI 1.48, 1.82), male sex (Male vs female OR 1.15; 95% CI 1.10-1.19), White race compared to non-white (OR1.10; 95% CI 1.06, 1.14), 7-10 years between exams compared to 3-5 years between exams (OR 1.24; 95% CI 1.11, 1.37), indication of surveillance vs. screening for the index exam (OR 1.1.7; 95% CI 1.13, 1.22), advanced adenoma or sessile serrated lesion finding on the index exam (OR 2.08; 95% CI 1.97, 21.9 and OR 1.23; 95% CI 1.16, 1.30 respectively).

[CONCLUSION] Our findings show endoscopist ADR and WT for both index and surveillance colonoscopy are associated with risk of metachronous neoplasia, including CRC. Future studies on metachronous neoplasia should include both sets of quality indicators.