BackgroundThis study aims to evaluate the impact of Quebec’s first hospital-at-home-inspired mobile Seniors’ Clinic, the “Clinique des Ainés (CDA)”, on frail older adults’ returns to the Emergency Department (ED), mortality, and hospital Length Of Stay (LOS) and rehospitalizations.MethodsDesign: Quasi-experimental pre-post implementation cohort study. Population: Patients aged ≥ 75 years admitted to the short-term geriatric unit after an ED consultation (control) or included by the CDA (intervention). Outcomes: return to ED (RtoED), mortality, ED & hospital LOS, and rehospitalizations. Statistical analyses: Multivariable regression modelling.ResultsOverall, 891 patients were included. At the intervention site (CDA) (n = 437), RtoED were similar at 30 (17.5% & 19.5%, p = 0.58), 90 (34.4% & 37.3%, p = 0.46) and 180 days (47.2% & 54.0%, p = 0.07) in the pre and post-implementation phases. No mortality differences were found. The hospitalization LOS was significantly shorter (28.26 and 14.22 days, p < 0.01). At 90 days, rehospitalization LOS was decreased by 8.51 days (p = 0.02) and by 6.48 days at 180 days (p = 0.03). Compared to the control site (n = 454) in the post-implementation phase, RtoED was 54% at the intervention site compared to 44.1% (p = 0.02) at 180 days. The CDA had a lower adjusted probability of mortality at 90 days compared to the control site (4.8% VS 11.7%, p = 0.03). No rehospitalization LOS differences were noted.ConclusionsThe Clinique des Ainés showed effectiveness in caring for frail older patients in their homes by decreasing their hospital LOS by half and 90 days mortality risk. It was a safe care trajectory without a clinically significant increase in ED returns or mortality.