Long-term outcomes and associated factors of Crohn’s disease patients achieving transmural healing based on magnetic resonance enterography: a Chinese retrospective cohort study

Background:Transmural healing (TH) has emerged as a potential treatment goal for Crohn’s disease (CD). However, further research is needed to confirm its benefits and risk factors associated with TH remain unclear.Objectives:We aimed to assess the value of TH based on magnetic resonance enterography (MRE) in Chinese CD patients regarding the long-term outcomes and its associated factors.Design:Retrospective, observational cohort study.Methods:Patients with CD diagnosed by colonoscopy and MRE examination between 2015 and 2022 were included. All patients were evaluated with endoscopy together with MRE within 6–12 months after baseline and followed up for at least 6 months after evaluation. The primary endpoint was the occurrence of major outcomes during the follow-up, including drug escalation, hospitalization, and surgery. The cumulative probabilities of major outcomes were calculated using Kaplan–Meier survival curves. Logistic regression analyses were used to predict TH within 6–12 months after baseline.Results:A total of 175 patients were included in the study. Of these, 69 (39.4%) patients achieved mucosal healing (MH), but only 34 (19.4%) of them achieved TH. The median follow-up duration was 17.4 months (interquartile range, 11.6–25.5), and major outcomes occurred in 58.3% of patients. A lower occurrence rate of major outcomes was noted in patients who achieved TH than in those who achieved MH only ( p = 0.012). The baseline lymphocyte/C-reactive protein ratio (LCR) [odds ratio (OR), 1.60; 95% confidence interval (CI), 1.02–2.50; p = 0.039] and bowel wall thickness (BWT) (OR, 0.72; 95% CI, 0.59–0.90; p = 0.003) were independent predictors associated with TH. According to multivariate Cox regression analysis, low LCR [hazard ratio (HR), 2.34; 95% CI, 1.51–3.64; p < 0.001], and no healing (HR, 5.45; 95% CI, 2.28–13.00; p < 0.001) were associated with an increased risk of major outcomes.Conclusion:Patients with CD who achieved TH showed improved prognosis compared to those who achieved MH only. Baseline LCR and BWT might predict TH.