[Rockwood Frailty Index as a prognostic classifier in hospital at home: an observational survival study]

To evaluate the association between the Rockwood Frailty Index (RFI) and survival across three populations in a Hospital-at-Home Unit (HaH): complex chronic patients, non-oncologic palliative patients (advanced organ failure, severe functional limitation and impaired physiological reserve) and oncologic palliative patients.

Retrospective longitudinal observational cohort study. SITE: Hospital-at-Home Unit of the Hospital Universitari i Politècnic La Fe (Valencia, Spain).

Patients aged 65 or older discharged between January 2021 and December 2024, with an RFI recorded at admission and follow-up in the Case Management programme. 2,610 patients were included (53.8% complex chronic; 34.0% non-oncologic palliative; 12.2% oncologic palliative).

None; observational study with no intervention. MAIN: measurements Survival (time to death) using Kaplan-Meier curves, log-rank tests and multivariate Cox regression, adjusted for demographic (age, sex), clinical (Charlson and Barthel indices, diagnosis-related group, prior emergency admissions) and laboratory variables (albumin, C-reactive protein, glomerular filtration rate).

Significant differences were observed between groups (χ²=231; P<.001), with median survival of 449, 248.5 and 125days. The RFI was independently associated with higher mortality (HR 2.50; 95%CI: 1.66-3.76), outperforming the Charlson index (HR 1.05).

The RFI is a powerful independent prognostic predictor across all three populations, outperforming comorbidity and functional dependency. A threshold of ≥0.53 identifies non-oncologic patients with advanced organ failure and severe functional impairment -median survival below nine months- without a formal palliative designation. Its implementation in Primary Care electronic health records would enable early identification of this population and anticipate end-of-life palliative care, regardless of diagnosis.