The healthcare systems are under increasing pressure due to a rise in emergency consultations, staff shortages, an ageing population and rising costs. Emergency departments are seeing more vulnerable patients, including elderly people, who are often on multiple medications and at risk of medication errors.

To improve safety, the integration of pharmacists specialising in emergency medicine has proven beneficial: their presence in the team improves the detection of medication-related problems, speeds up and optimises treatment, reduces rehospitalisations and lowers healthcare costs. However, in most countries, these pharmacists are still rarely found in emergency departments, mainly due to a lack of resources and clinical prioritisation criteria tailored for them and adapted to this environment.

Frailty screening tools and scores, such as ISAR, can be used to identify the elderly patients most at risk, predict adverse events such as fall or mortality, and thus adapt their care in the emergency department. Indeed, elderly frail patients often take many medications and consequently are at risk of medication errors, adverse events, inappropriate prescriptions or serious drug interactions. These patients may therefore require a specialised review on their medication by clinical pharmacists when they are admitted to the emergency department, but their high number make it impossible to care for all of them.

We aim thus to evaluate the association between frailty (according to the ISAR score) and medication-related problems among elderly patients admitted to the emergency department. Researchers will examine whether this score can predict the presence of inappropriate prescribing and high-risk drug interactions. If so, pharmacists would then have a quick and easy tool to prioritise patients who would benefit most from a specialised review of their medications when they visit the emergency department.

There will not be any intervention and this study will not influence patients care. Once patients agree to participate, researchers will prospectively collect medical data from elderly patients admitted to the emergency department and analyse their medical history, home medication, reason for admission, frailty score using ISAR, and perform a pharmaceutical analysis based on these data.

Inclusion Criteria:

• Patients aged ≥ 75 years admitted to the adult emergency department
• Patients able to give informed consent as documented by signature or a therapeutic representative, if applicable .

Exclusion Criteria:

• Patients initially admitted to the emergency resuscitation room.
• Patients admitted to the minor accidents and emergencies room.
• Patients admitted to the stroke unit, as they just pass through the emergency department to directly proceed to the CT-scanner.
• Missing data for proper file analysis (e.g., missing usual home medication)
• Patient's inability to sign consent and no therapeutic representative available
• Patient's refusal to sign consent
• Emergency physician's refusal to include patient for any reason.

The study population will consist of all geriatric patients residing in the area of the Riviera-Chablais Hospital (Rennaz, Canton of Vaud, Switzerland). This hospital cares for nearly 200,000 people and its adult emergency department receives 35,000 patients per year (20% of whom are aged 75 and over).

If patients give their consent for data re-utilisation (consent signature independent from their inclusion in the study), demographic data and all individual outcomes (ISAR score, inappropriate prescriptions, high-risk drug interactions, drug-related problems, AT-HARM10 score) will be shared. All data will be anonymised and shared in a secure format (CSV).

IPD data will be available 6 months after publication of the first study results and for 10 years

Data will be accessible to external researchers, regulatory bodies, and authorized entities under the following conditions:

Formal request submission detailing the project and data usage. Access granted if the request meets ethical, scientific, and confidentiality criteria.