Muscle Function Impairment in Crohn’s Disease Patients: Risk Factors and Clinical Implications—Single-Tertiary-Center Experience

Sarcopenia in inflammatory bowel disease can significantly influence disease course. Since current assessment focuses mainly on muscle quantity, we aimed to evaluate muscle function in Crohn’s disease (CD) patients and identify those at increased risk of muscle function impairment. This cross-sectional study included 84 patients with CD (76.2% male, mean age 35 ± 11 years) receiving infliximab. Body composition was assessed by bioelectrical impedance analysis, muscle strength by handgrip strength (HGS), and physical performance by gait speed. Half of the cohort demonstrated reduced muscle strength relative to age- and sex-adjusted norms, while none met criteria for confirmed sarcopenia. One third of the patients had low physical performance and only one patient screened positive for sarcopenia. In multivariable linear regression, sex was the strongest independent predictor of HGS (p < 0.001), followed by ileocolonic disease localization, which was independently associated with lower HGS compared to ileal (p = 0.045) and colonic (p = 0.046). Hemoglobin remained an independent predictor of HGS after multivariable adjustment (p = 0.021). Low muscle strength is common in patients with CD treated with infliximab, even in the absence of low muscle mass. Ileocolonic disease localization and lower hemoglobin levels are predictors of low muscle strength, highlighting the importance of early and comprehensive muscle function assessment in this population.