Studies have documented the underuse of oral anticoagulant therapy (OAC) as stroke prophylaxis in older persons with history of atrial fibrillation (AF). Failure to prescribe OAC is often due to the perception by physicians of bleeding because of specific older people clinical factors. We performed a prospective observational study in the University Hospital of Reims, whose aim was to evaluate the management of thromboembolic risk in older patients in everyday-life hospital practice and impact of frailty and dependence objective parameters. 150 AF patients over 75 years were consecutively included over a period of four months. Clinical and biological data, risk scores for bleeding (HASBLED) and thrombo-embolic events (CHADS and CHADSVASc) were computed. Several scores and parameters of assessment of autonomy and risk of falling were independently recorded: MMS (Mini-Mental Status), ADL (Activities of Daily Living) and IADL (Instrumental ADL). Mean age was 83±13 years (75 men). At discharge, 52.2% of patients were under OAC. Mean CHADS, CHADSVASc and HASBLED score were respectively 2,6±0,1, 4,6±0,1 and 2,3±0,1; all patients had a CHA DS VASc score ≥2 and 86% a CHADS ≥2. The HASBLED score was associated with non-prescription of anticoagulation (p=0.001), while none of the thrombo-embolic scores was significantly associated with prescription. Specific studied parameters are in table. Anticoagulation N=74 No anticoagulation N=68 p Age (years) 81.8±0.5 84.6±0.6 0.001 Creatinine (μmol/l) 106±7.3 127.3±6.3 0.03 Dependency (%) 27 54 0.001 Dementia (%) 4,1 14,7 0.04 High risk of falling (%) 0 20 0,001 MMS score 21.4±1.2 20.1±1.1 NS ADL score 5.1±0.3 3.8±0.4 0.001 IADL score 2±0.2 2.4±0.4 NS In our study of everyday practice, there is an underuse of anticoagulation in the elderly compared to guidelines, mainly because the perception of the hemorrhagic risk prevails over the thrombo-embolic risk. Specific geriatric parameters could help to choose the appropriate therapy.