NPPB and diabetes mellitus: Increased risk of (NT-pro) BNP-guided therapy was observed if renal failure was present (p < 0.01), and (NT-pro) BNP-guided therapy was beneficial only if none or one of the comorbidities, such as chronic obstructive pulmonary disease, diabetes, cardiovascular insult, or peripheral vascular disease, was present (p < 0.01).