OBJECTIVES: The use of low-osmolar contrast media has reduced the frequency of Contrast-Induced Nephropathy (CIN), however, it still exists. As no data are available in France, a study was set up to estimate the hospital burden associated to this complication in terms of medical resource used and hospital costs. METHODS: A retrospective, observational study was conducted using the French exhaustive hospital discharge database (PMSI). Stays with an interventional radiology or cardiology procedure involving the use of a contrast media were identified in 2012 and 2013 in adults. CIN was defined as the occurrence over the stay of a nephropathy CIM-10 code or unscheduled dialysis procedure. Patients’ characteristics and stays were described, as well as associated costs. RESULTS: In 2012 and 2013, 1,047,329 stays were identified with an interventional procedure. Patients were mainly men (68.0%) with a mean age of 66.1±13.8. Among those patients, 25.8% were diabetics, 9.2% had Chronic Kidney Disease (CKD), 3.4% were suffering from heart failure and 0.2% had a cardiogenic shock. Overall CIN rate was 3.1%. CIN resulted in an extra length of stay (LOS) of 15.8 days (20.5 vs 4.7 days, p<0.0001) and an extra cost of €12,413 (€15,765 vs€3,352, p<0.0001). This result was very similar in each sub-group analysis (extra cost of €11,030 for diabetics, €11,437 for CKD and €7,257 for patients with heart failure). In France, the hospital cost of CIN reached a total cost €401,023,050 in 2012 and 2013, making it €200,511,525 per year. CONCLUSIONS: This study shows that CIN was associated with significant hospital costs due to increased LOS, even more when dialysis occurred. The hospital cost of CIN could partially cut down through better preventing measures including safer media use.