OBJECTIVE: To estimate the French hospital extra costs of cardiovascular events (CVE) occurring in diabetic and non diabetic patients. METHODS: Hospital stays were extracted from the 2003 national Diagnosis Related Group (DRG) including the whole French stays (around 18 million records). Stays were selected on the ICD-10 and/or procedures codes related to the following events: stroke, myocardial infarction, unstable angina, and coronary revascularisation. Diabetic patients were picked out using secondary diagnosis related to diabetes mellitus (type I and II). The level of resource consumption and average length of stay were analyzed in both diabetic and non diabetic groups. For the economic analysis, an adjustment method based on national DRG costs (public and private hospitals) was used to take into account extra length of stay of diabetic patients compared with average DRG length of stay. RESULTS: Average length of stay of diabetics was significantly longer than non diabetics (stroke: 2.45 days, myocardial infarction: +1.48 days, unstable angina: +1.25 days, revascularisation: 2.82 days; p<0.001 for each). The mean number of medical procedures recorded by stay was higher in the diabetic group (stroke: +0.51; myocardial infarction: +0.80, unstable angina:+0.92, revascularisation: +1.91; p<0,001 for each) and diabetic patients had more Intensive Care Unit transfer for myocardial infarction and unstable angina (odd ratio diabetic versus non diabetic: 1.7 and 1.3; p<0.001). Adjusted hospitalization costs of events for diabetic patients were the following: stroke (non fatal event): €5703, myocardial infarction (non fatal event): €4,721, unstable angina: €4,147, coronary revascularisation: €11,679. The overcosts of diabetic patients for these events compared with average DRG cost were respectively +23.9%, +10.4%, +6.1 % and +9.1 %. CONCLUSION: Diabetic patients with CVE required higher medical consumptions than non diabetic during hospital management. Extra costs associated with diabetes were estimated and can be used in cost-effectiveness studies.