OBJECTIVES: The risk of cardiovascular risk is higher in patients with diabetes but what with the cost of this complication? The aim of this study was to compare the cost of cardiovascular events in patients with and without diabetes in Belgium.  METHODS: Cost of cardiovascular events among hospitalized patients were estimated using the longitudinal IMS Hospital Disease Database (2008), including data on 34.3% of Belgian hospital beds, combined with Belgian population data. Stays were identified based on ICD-9 or DRG coding. Cardiac disease included myocardial infarction (MI; ICD-9:410), angina (ICD-9: 413) and heart failure (ICD-9: 428). Cerebrovascular disease (CVD) was defined as stroke (APR-DRG:045;046) and Transient Ischemic Attack (TIA; DRG:047). Diabetes was defined with the ICD-9 codes 249 and 250. Cost comparisons were made using a Wilcoxon non-parametrical test.  RESULTS: An MI in a diabetic patient was 35% more expensive compared to a non diabetic (€7,483 vs. €5,549; p<0.001). In angina and heart failure the difference was less pronounced, nevertheless the cost was respectively 22% and 13% higher (angina: €2,570 vs. €2,101; p=0.01, heart failure: €8,776 vs. €7,757; p<0.001). Stroke was 8% more expensive and TIA 17% more expensive (stroke: €9,508 vs. €8,804; TIA: €4,802 vs. €4,109; both p<0.001). Reason for this higher cost is the longer length of stay varying from 1 day in angina to 3 days in MI. The percentage of women was higher in the diabetic group (50% vs. 47%; p<0.05) and diabetic patients were on average 1.8 years older (72.8 vs. 71.0; p<0.01). A regression analysis learned that age was the most important cost driver for all outcomes and diabetes was an independent driver for MI and stroke.  CONCLUSIONS: Patients with diabetes do not only have a higher risk of cardiovascular events, in case they have an event this event is significantly more expensive.