 We suppose that many of hospitalized elderly have at least one prescribed medication without valid indication. Conversely, many diseases are currently undertreated in elderly patients: e.g. medicines used to treat heart failure and osteoporosis are underused in 20 to 70 of patients. Moreover, PMI prescription is associated with an increased of morbidity, mortality, risk of drug-related adverse events, utilization of health care system, care costs and impairment of quality of life. Thus, optimization of drug prescription is a major concern for improvement of the quality and safety of care in elderly. 