Parameters of body composition and creeping fat are associated with activity of Crohn's disease

Aim: This study aimed at assessing body composition parameters, creeping fat (CrF), and Crohn's disease's (CD) activity based on the Magnetic Resonance Index of Activity (MaRIA). Methods: 114 CD patients who underwent magnetic resonance enterography (MRE) between June 2010 and April 2020 were retrospectively assessed. The semi-automated body composition segmentation, the qualitative eval-uation of CrF, and MaRIA were performed. Based on their MaRIA score, patients were divided into two groups: mild-to-moderate disease (MaRIA <11, n = 50) and severe disease (MaRIA >= 11, n = 64). MRE parameters were analyzed between both groups. Patients were dichotomized according to body composition categories and the presence of CrF. Univariate regression analyses were performed to investigate the association between dichot-omized variables and severe disease. Significant variables were incorporated into the multivariate logistic regression model. Results: The severe disease group exhibited higher serum C-reactive protein (CRP) levels compared to the mild-to-moderate disease group (p <0.001). In the mild-to-moderate disease group, a higher proportion of patients had a body mass index (BMI) >= 25 (kg/m2) (32.0%) compared to the severe disease group (16.5%) (p = 0.04). The subcutaneous adipose tissue index (SATI) was significantly higher in the mild-to-moderate disease group (p = 0.04). The visceral to subcutaneous adipose tissue (VAT/SAT) ratio tended to be higher in the severe disease group (p = 0.09). There was no significant difference between both groups regarding total adipose tissue index (TATI) (p = 0.10), visceral adipose tissue index (VATI) (p = 0.51), intramuscular adipose tissue index (IMATI) (p = 0.38), skeletal muscle index (SMI) (p = 0.83), and sarcopenia (p = 0.75). In the multivariate analysis, CrF was significantly associated with severe disease (odds ratio [OR] 11.50, 95% confidence interval [CI] 3.13-42.17; p <0.001). Additionally, a BMI >= 25 (kg/m2) was protective against severe disease (OR: 0.34, 95% CI 0.12-0.95; p = 0.04). Conclusion: CrF is significantly associated with CD activity.