Defining Endoscopic Remission in Crohn’s Disease: MM-SES-CD and SES-CD Thresholds Associated With Low Risk of Disease Progression

Background & Aims

We assessed Modified Multiplier Simple Endoscopic Score for Crohn’s Disease (MM-SES-CD) and Simple Endoscopic Score for Crohn’s Disease (SES-CD) thresholds that are best associated with low likelihood of long-term disease progression.

Methods

Data from 61 patients with early Crohn’s disease (CD) who participated in the CALM long-term extension study were used as the derivation cohort and validated using the McMaster inflammatory bowel disease database (n = 99). The primary outcome was disease progression (new internal fistula/abscess, stricture, perianal fistula or abscess, CD-related hospitalization or surgery) since the end of the CALM trial. Optimal MM-SES-CD and SES-CD thresholds were determined using the maximum Youden index. Receiver operating characteristic curve analyses compared threshold scores of remission definitions on disease progression.

Results

In the derivation cohort, based on the maximum Youden index, the optimal thresholds associated with a low likelihood of disease progression were MM-SES-CD <22.5 and SES-CD <4. A significantly greater proportion of patients with a MM-SES-CD ≥22.5 had disease progression as compared with patients in the derivation cohort with MM-SES-CD <22.5 (10/17 [58.8%] vs 3/44 [6.8%]; P < .001). Similarly, a significantly greater number of patients with SES-CD ≥ 4 had disease progression compared with those with a SES-CD <4 (11/25 [44.0%] vs 2/36 [5.6%]; P < .001). Compared with other clinical or endoscopic remission definitions, which demonstrated poor to fair accuracy, MM-SES-CD <22.5 performed the best for predicting disease progression (area under the curve = 0.81; 95% confidence interval, 0.68-0.94; P < .001). These thresholds were confirmed in the validation cohort.

Conclusion

Achievement of MM-SES-CD <22.5 or SES-CD <4 in patients with ileocolonic or colonic CD is associated with low risk of disease progression and may be suitable targets in clinical trials and practice for endoscopic healing.