Contribution of GFAP and UCH-L1 Assays in Whole Blood to Optimizing Personalized Care for "Repeated Fallers" Hospitalized in Geriatric Wards

The BACHUS study focuses on a population of patients aged 75 years and older who are hospitalized after recurrent falls. The objective is to evaluate the performance of an innovative, personalized biological screening strategy to detect intracranial hemorrhages, as an alternative to brain CT scanning, which is often difficult to access within the required time frame in elderly patients.

Patients included in the study will undergo two blood measurements of the biomarkers GFAP and UCH-L1 performed on whole blood using a portable device such as the i-Stat Alinity. The first measurement will be performed within 72 hours of admission in order to establish an individual baseline value, given the impossibility of relying on average reference values in this population, which is subject to variability in biomarker levels due to confounding factors.

In the event of a new fall during hospitalization, and when a brain CT scan is deemed necessary by the referring physician, a second measurement will be performed within the time window recommended by the French National Authority for Health (HAS) (6 to 12 hours after the fall), ideally before the CT scan. Apart from the addition of this blood sample, the study will not modify usual patient management, with the decision to perform a CT scan remaining at the clinician's discretion.

The primary endpoint is the diagnostic performance of this personalized strategy (sensitivity, specificity, predictive values) compared with brain CT scanning, which remains the reference standard. The results will make it possible to estimate the number of CT scans that could be avoided. Secondary endpoints will allow further refinement of the analysis according to patient profile (age, sex, cognitive status, anticoagulant therapy, nutritional status, etc.).