Association between Clinical Characteristics and Sarcopenia or Sarcopenic Obesity in Crohn's Disease

Objective Crohn's disease (CD) is a chronic inflammatory bowel disease that is associated with malnutrition. Sarcopenia is a malnutrition condition characterized by skeletal muscle loss that impairs the physical function. We investigated the clinical characteristics of patients with CD with sarcopenia and sarcopenic obesity (sarcopenic-o). Methods The body composition of patients with CD was evaluated using a bioelectrical impedance analysis. The clinical characteristics of patients with sarcopenia and sarcopenic-o were analyzed, and a predictive model for sarcopenia was developed. Patients Patients with CD recruited from 2019 to 2021 were included. Results Among the 104 patients, 35 (33.7%) and 10 (9.6%) had sarcopenia and sarcopenic-o, respectively. In the sarcopenia group, the skeletal muscle index (SMI) and body mass index (BMI) were lower than those in the control group (SMI, 6.3 kg/m² vs. 7.7 kg/m², p<0.01; BMI, 18.8 kg/m² vs. 22.6 kg/m², p<0.01), whereas the Crohn's disease activity index (CDAI) was higher than in the control group (114.2 vs. 42.0, p<0.01). The predictive models of sarcopenia using the BMI and CDAI revealed high performance with areas under the receiver operating characteristic curve (AUC) of 0.87 and 0.72, respectively, and high specificity (0.94) and sensitivity (0.71), respectively. Sarcopenic-o patients could not be screened using the BMI (25 kg/m²), and the SMI and body fat percentage were negatively correlated in patients with sarcopenia (p<0.01). Conclusion Sarcopenia and sarcopenic-o are relatively common conditions among patients with CD. Sarcopenia can be predicted using the clinical parameters of BMI and CDAI. Sarcopenic-o can be a severe form of sarcopenia.