Magnetic resonance imaging-based simplified MaRIA scores are associated with future surgery in Crohn's disease, but modest correlation with ileo-colonoscopic inflammation limits their utility in clinical trials: results from the PROFILE trial.

BACKGROUND

Ileo-colonoscopy provides accurate assessment of mucosal inflammation in Crohn's disease. Magnetic resonance imaging (MRI) offers a non-invasive alternative. MRI-based scores such as the simplified MaRIA (sMaRIA) have been proposed for measuring treatment response in clinical trials, but systematic comparisons with endoscopic scoring systems in prospective datasets are lacking.

METHODS

PROFILE trial participants underwent ileo-colonoscopy and small bowel MRI at baseline and week 48 (end-of-trial). Using this dataset our primary objective was to assess the correlation between Simple Endoscopic Score for Crohn's Disease (SES-CD) and sMaRIA scores using contemporaneous ileo-colonoscopy and MRI studies. We also assessed the utility of sMaRIA as a clinical trial endpoint, and correlation between baseline sMaRIA and need for future surgery. Endoscopic and MRI remission were defined as SES-CD and sMaRIA scores of 0. Ulcer subscores were also examined.

RESULTS

In total, :285 patients had paired baseline ileo-colonoscopy and MRI studies and 220 had paired end-of-trial studies-undertaken a median of 35 and 22 days apart respectively. Correlation between total SES-CD and sMaRIA scores on end-of-trial studies was moderate (Spearman's ρ = 0.428). MRI/sMaRIA identified only 18/143 ulcerated segments seen on ileo-colonoscopy. While remission rates between PROFILE treatment arms were significantly different on ileo-colonoscopy/SES-CD (P = .005), this difference was not seen on MRI/sMaRIA (P = .564). Patients requiring abdominal surgery had higher baseline sMaRIA scores than those who did not (P = .015), while SES-CD scores were not different between these groups (P = .830).

CONCLUSIONS

MRI should be considered as complementary to ileo-colonoscopy for assessing ileal Crohn's disease. sMaRIA should not replace SES-CD in clinical trials.