Quantification of visceral adipose tissue volume predicts both short-term and long-term transmural healing in patients with Crohn's disease receiving Ustekinumab.

Background: Transmural healing (TH) is an emerging therapeutic target in Crohn's disease (CD). Visceral adipose tissue (VAT) is associated with the prognosis of CD, but few studies investigate the ability of VAT in predicting TH. Objectives: We aimed to quantitatively assess VAT by magnetic resonance enterography (MRE) and evaluate the prediction of baseline VAT volume for TH in CD patients with Ustekinumab (UST) treatment. Design: This is an observational study. Methods: We retrospectively included CD patients receiving UST treatment, with bowel wall thickness (BWT) >3 mm assessed by MRE at baseline. Clinical characteristics, laboratory, endoscopic, and MRE indicators were evaluated at baseline, week 26 (W26), and week 78 (W78) of the therapy. Quantification of VAT volume was assessed by MRE at baseline, and adjusted by body mass index (BMI). The TH was defined as BWT ⩽3 mm without any signs of inflammation at W26 and W78. Results: Sixty-two patients were included in our study. After UST treatment for W26 and W78, 8 (13.1%) and 13 (21.0%) patients achieved TH. Compared with baseline, laboratory indicators such as C-reactive protein and erythrocyte sedimentation rate, simple endoscopic score for CD, and BWT were significantly improved at W26 and W78. We divided patients into the TH and non-TH groups at both W26 and W78, and found that adjusted VAT volume at baseline was significantly lower in the W26-TH and W78-TH groups. Adjusted VAT volume was then categorized into four scores by quartiles, and multivariable analysis showed that baseline VAT score could negatively predict W26-TH (odds ratio (OR) = 0.296, Conclusion: Our study demonstrated that baseline VAT was an independent risk factor for predicting both short- and long-term TH in CD patients receiving UST. Patients with lower VAT volume at baseline were more likely to achieve TH after UST treatment.