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Higher Sessile Serrated Lesion Detection Rates Calculated Using All Examinations Are Associated With Lower Risk for
Rachael Hagen1, Douglas K Rex2, Todd A MacKenzie3
1Department of Medicine, University of Connecticut, Farmington, Connecticut, USA.
Introduction:
Calculating detection rates using data from colonoscopies for all indications, rather than screening examinations, is simpler and can mitigate gaming by endoscopists. We hypothesized that calculating sessile serrated lesion detection rates (SSLDR-A) using all examinations may also be a quality metric for predicting postcolonoscopy colorectal cancer (PCCRC) risk.
Methods:
The cohort included New Hampshire Colonoscopy Registry 115,762 patients with an index colonoscopy. The primary outcome was PCCRC, defined as colorectal cancer (CRC) diagnosed ≥6 months after the index colonoscopy. The exposure variables were endoscopist-specific SSLDR-A (using all examinations) and SSLDR-S (using screening examinations), stratified into quintiles. Cox regression was used to model the hazard of PCCRC on SSLDR, adjusting for relevant covariates, such as patient age and sex.
Results:
There were 177 PCCRCs diagnosed in 115,762 patients with index colonoscopies. Higher SSLDR-A and SSLDR-S rates were associated with lower PCCRC risks. After adjusting for covariates, we observed that higher SSLDR-A rates were associated with lower hazard ratios (HRs) as compared with the reference group (SSLDR-A: <1.5%; HR = 1.0 vs SSLDR-A: 1.5% to <3.0%; HR = 0.53, 95% CI 0.35-0.79; SSLDR-A: 3.0% to <5.0%; HR = 0.59, 95% CI 0.38-0.92; SSLDR: 5.0% to <8.0%; HR = 0.44, 95% CI 0.28-0.70; and SSLDR: 8.0+%; HR = 0.20, 95% CI 0.08-0.46). The highest quintile of SSLDR-A (8.0%+) (HR = 0.20, 95% CI 0.08-0.46) and SSLDR-S (8.0%+) (HR = 0.20, 95% CI 0.09-0.44) provided similar protection from PCCRC.
Discussion:
These findings demonstrate that colonoscopies performed by endoscopists with higher SSLDR-A are associated with a lower risk of PCCRC, validating SSLDR-A as a quality metric. Furthermore, our data suggest that endoscopists should aim for an SSLDR-A of 6% and have an aspirational SSLDR-A of 8.0% or higher.
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