The effect of biological agent on body composition in patients with Crohn's disease

Crohn's disease (CD) is associated with altered body composition, affecting clinical outcomes. We evaluated the impact of biologics on body composition in CD patients.

This multicenter longitudinal study across four Korean university hospitals conducted from January 2009 to August 2021 retrospectively reviewed data of CD patients with abdominal computed tomography (CT) before and after the biologic treatment. Skeletal muscle area (SMA), visceral fat area (VFA), and subcutaneous fat area (SFA) of the third lumbar vertebra (L3) on CT were measured. Myopenia was defined as L3 skeletal muscle index (SMI) of < 49 and < 31 cm²/m² for men and women, respectively.

Among 112 participants, 79 (70.5%) had myopenia. In the myopenia group, all body composition parameters were significantly increased after the biologic treatment: SMI (37.68 vs. 39.40 cm²/m²; P < 0.001), VFA (26.12 vs. 54.61 cm²; P < 0.001), SFA (44.29 vs. 82.42 cm²; P < 0.001), while no significant differences were observed in the non-myopenia group. In multivariate analysis, penetrating CD (hazard ratio, 5.40; P = 0.020) was the independent prognostic factor for surgery. Operation-free survival rate tended to decrease in the myopenia group (Log-rank test, P = 0.090).

Biological agents can increase all body composition parameters in CD patients with myopenia. These patients are more likely to experience surgery.