NPPB and type 2 diabetes mellitus: With the aim of comparing the difference in accumulation of clinical outcomes between four subgroups of HF patients with T2DM during 56-week observation period depending on the compartments of circulating biological markers (high/high levels low/low, low/high, high/low, and of NT-proBNP and irisin, respectively) we computed Kaplan-Meier curves (Figure 4).