AIMS: Cardiogenic shock is the leading cause of in-hospital mortality after acute myocardial infarction (MI). This study investigates the importance of age and preexisting diabetes mellitus on the incidence and prognosis of cardiogenic shock in a large group of consecutive patients with MI. METHODS AND RESULTS: Baseline characteristics and in-hospital complications to the infarction were prospectively recorded in 6676 patients with MI. Ten-year mortality was collected. Diabetes was present in 10.8% of the total population. A total of 443 developed cardiogenic shock with an incidence of 6.2% among nondiabetics and 10.6% among diabetics. Age, wall motion index, reinfarction, and the absence of thrombolytic treatment were significant independent predictors of mortality in patients with cardiogenic shock. Intriguingly, diabetes was not a significant predictor for short- and long-term mortality in this population. The 30-day and 5-year mortality rate was equally poor in both diabetic and nondiabetic patients with cardiogenic shock (diabetics: 30-day 63%, 5-year 91%; nondiabetics: 30-day 62%, 5-year 86%; p>0.05). CONCLUSIONS: Cardiogenic shock develops approximately twice as often among diabetics as among nondiabetic patients with acute MI. The prognosis of diabetics with cardiogenic shock is similar to the prognosis of nondiabetic patients with cardiogenic shock.