Adiponectin and phase angle in the assessment of sarcopenia in Crohn's disease: beyond muscle mass

Sarcopenia is a common and clinically relevant complication of Crohn's disease (CD), reflecting the cross-link among chronic inflammation, malnutrition, and metabolic dysregulation. Adiponectin, an anti-inflammatory adipokine, and phase angle, a marker of cellular integrity, have emerged as potential indicators of muscle health. This study aimed to evaluate the role of anthropometric and inflammation parameters in 150 CD patients.

Anthropometric and bioimpedance parameters including handgrip strength and PhA were collected to define sarcopenia according to EWGSOP2. Additionally, the levels of adiponectin and inflammatory cytokines (IL-6, IL-1β, TNF-α, CRP) were tested by ELISA. Adiponectin oligomeric status was assessed by Western Blotting.

Sarcopenia was identified in 8% and pre-sarcopenia in 71% of patients. Interestingly, sarcopenic and pre-sarcopenic patients were significantly younger and had lower BMI, fat-free mass, and skeletal mass compared to non-sarcopenic individuals (p < 0.05). Phase angle values were also statistically lower in sarcopenic subjects (5.06 ± 0.67°). Adiponectin levels were significantly reduced in sarcopenic (14.0 ± 5.2 μg/mL) compared to pre-sarcopenic and non-sarcopenic patients (20.1 ± 4.5, 20.2 ± 3.6 μg/mL, respectively p < 0.05). The ROC analysis identified both adiponectin and PhA as accurate predictors of sarcopenia risk in CD. Analysis of adiponectin oligomers evidenced a significant down regulation of HMW and MMW isoforms in sarcopenic vs. pre-sarcopenic and non-sarcopenic patients.

Our findings support the pivotal role of metabolic and nutritional disorders in muscle loss in CD patients and indicate adiponectin and phase angle as complementary biomarkers of sarcopenia. Furthermore, our results, highlight the interplay among inflammation, adipose tissue dysfunction, and muscle wasting in Crohn's disease.