FNDC5 and hypertensive disorder: As for irisin, in addition to statistically significant differences in FLI and liver stiffness between the groups of patients with MASLD and HTN with serum irisin concentrations < 6.1 μg/mL and ≥6.1 μg/mL, minor differences were also confirmed in WC (p = 0.082) and blood triglyceride levels (p = 0.062).