DOP036. Lémann Index assessment over time in Crohn's disease patients treated with anti TNFs: a pilot observational cohort study
G. Fiorino1, M. Allocca1, C. Bonifacio2, P. Naccarato1, F. Mrakic Sposta2, A. Spinelli3, L. Balzarini1, S. Danese1, 1Humanitas Research Hospital, IBD Center, Rozzano, Milan, Italy, 2Humanitas Research Hospital, Radiology, Rozzano, Milan, Italy, 3Humanitas Research Hospital, IBD Surgery Unit, Milano, Italy
Crohn's disease (CD) leads to complications and consequent bowel damage (BD). Recently, the Lémann Index (LI) has been developed to quantify BD. There are no data on the role of LI in assessing BD changes over time.
We aimed to explore the sensitivity and specificity, and the long-term progression of BD in a cohort of CD patients treated with anti TNF, measured by LI calculation.
This was a prospective observational cohort pilot study on consecutive CD subjects followed within 3 years. They all underwent an abdominal MRI and colonoscopy, and a pelvic MRI in case of perianal disease, before starting anti-TNF therapy and then each year. CD-related BD at baseline and at follow-up was graded using the LI by a trained IBD specialist. BD progression and regression were judged by an second indepent blinded IBD specialist, not aware of LI calculation. The primary outcome was to assess the sensitivity and specificity of LI to assess BD changes. Secondary outcomes were to assess the impact of anti-TNFs on BD, and the rate of surgery related with BD progression. Statistical analysis included χ2 test, ROC curve analysis and paired T-test for variance, logistic regression and survival analysis by Kaplan-Meyer curves and log-rank test. Any difference was considered statistically significant if p < 0.05.
Twenty-four CD patients were enrolled, 11 infliximab (IFX), 13 adalimumab (ADA). The mean baseline LI in the whole study population was 42.3 (range 14–134.3). Eleven subjects (45%) had perianal disease. Mean follow up was 37 months.
A LI >35 identified CD subjects with BD. A LI change greater or lower than 0 between baseline and FU was related to bowel damage progression (AUC 0.73, sensitivity 0.55, specificity 0.93, PLR 8.33) or regression (AUC 0.74, sensitivity 0.92, specificity 0.50, PLR1.86), respectively. Paired t-test showed no significant differences in the variance of baseline and FU LI (p = 0.17).
At follow-up, 75% of subjects had BD regression (IFX = 8; ADA = 10), while 29.6% of had BD progression (IFX = 3; ADA = 3). Mean difference in the BD score between baseline and follow-up was −0.92 (range −91.8 to 61.8). Seven subjects (29.1%) of the whole population had major bowel surgery due to symptomatic complications (IFX = 3; ADA = 4). Subjects with BD progression were more likely to undergo major surgery in the following 12 months (HR 0.13, 95% CI 0.04–0.29, p = 0.002). No statistically significant differences were found between IFX and ADA groups (p = 0.81).
Although in a small cohort, the Lémann index might be able to detect change in BD and to assess response to therapies. Anti-TNF may probably stop BD progression in the long term, as assessed by the LI. BD progression may be predictive of major surgery within 12 months.