Serum irisin level was significantly higher in the cachexia group than in the controls (Irisin (μg/mL); 2.6 (IQR:2.2–4.4) vs. 2.1 (IQR:1.8–2.4); p = 0.001), and positively correlated with BNP levels and NYHA class, and negatively correlated with BMI and serum albumin level (all p values: <0.001) [5]. The gene discussed is FNDC5; the disease is Cachexia.