Impact of the Crohn's disease digestive damage score (Lémann Index) on the perioperative course in patients with Crohn's disease and ileocolic anastomosis.

Background: Risk factors influencing the high postoperative morbidity in Crohn`s disease are controversially discussed but the role of cumulative structural bowel damage, as assessed by the Crohn's disease digestive damage score (Lémann Index), has been neglected so far. Our aim was evaluating the influence of the Lémann Index on postoperative complications and investigating its suitability for surgical decision making.

Methods: A single-center, retrospective cohort study was conducted including Crohn`s disease patients who underwent ileocolic anastomosis. Lémann Indices were calculated and, additionally, categorized into three groups [0-3; 3-10; >10] due to the strong influence of previous bowel resections on high indices. A multivariate regression model was used to analyze the index`s influence on postoperative complications.

Results: Patients with higher Lémann Index were more likely to need open surgery ( < .001) or stoma creation ( = .03). Overall, of the 103 patients enrolled, 18 (17.5%) showed postoperative complications Clavien-Dindo > 2. The Lémann Index was higher in patients with complications compared to those without (median 6.15 [IQR 4.16-11.98] vs. 3.88 [1.63-12.63]), but not linearly associated with postoperative complications. After categorization, patients with Lémann Index 3-10 had an 8.42 (95% CI 1.8-54.55) times higher chance to develop a complication compared to patients with Lémann Index 0-3 ( = .01).

Conclusions: The Lémann Index might affect surgical decision making but is not linearly associated with postoperative morbidity. However, medium indices (3-10) - mainly accounted for by high amounts of intraabdominal active Crohn`s lesions - showed significantly higher rates of complications, potentially defining a group at risk.