Plasma N-terminal Pro-Brain Natriuretic Peptide (Nt-proBNP) level has been shown to provide valuable prognostic information on short and long-term mortality in patients with acute Myocardial Infarction, in the general population. Increased plasma Nt-proBNP levels have been found in Type 2 diabetic patients with vascular complications or with hypertension. In a large prospective study performed in 560 patients hospitalized for acute Myocardial Infarction (RICO), we found that median Nt-proBNP levels were significantly higher in the 199 diabetic patients compared to the 361 non-diabetic patients (245 (81-77) vs. 130 (49-199) pmol/L, P<0.0001). This difference remained highly significant after adjustment for confounding factors and we have been able to show that diabetes, per se, was a strong and independent factor for increased plasma Nt-proBNP levels, in this population. In the prospective RICO survey, we have found, in multivariable analysis, that diabetes was an independent factor for in-hospital mortality (OR: 1.79 [1.45-2.20]; P=0.0064) and cardiogenic shock (OR: 1.45(1.22-1.72); P =0.0364) when the variable Nt-proBNP level was not introduced into the model, but was less significantly associated with mortality (OR: 1.73 (1.39-2.16); P=0.0107) and no longer associated with cardiogenic shock when Nt-proBNP was in the model. This data suggest that increased plasma Nt-proBNP may be one of the links between diabetes and poor short-term prognosis after Myocardial Infarction and provides highly valuable prognostic information on in-hospital outcome in diabetic patients.