Indeed, irisin demonstrated its predictive potency for HFpEF and indicated a possibility of improving the predictive ability of NT-proBNP during a period of slightly elevated concentrations, which could have serious clinical significance in T2DM with abdominal obesity, in whom natriuretic peptide levels appeared to be lower than in patients with normal or near-normal body weight. Here, FNDC5 is linked to type 2 diabetes mellitus.