Site of care and factors associated with mortality in unvaccinated Australian aged care residents during COVID‐19 outbreaks

Background Residential InReach presents an alternative to hospital admission for aged care residents swabbed for coronavirus disease 2019 (COVID-19), although relative outcomes remain unknown. Aims To compare rates and predictors of 28-day mortality for aged care residents seen by InReach with COVID-19, or 'suspected COVID-19' (sCOVID), including hospital versus InReach-based care. Methods Prospective observational study of consecutive patients referred to a Victorian InReach service meeting COVID-19 testing criteria between April and October 2020 (prevaccine availability). COVID-19 was determined by positive polymerase chain reaction testing on nasopharyngeal swab. sCOVID-19 was defined as meeting symptomatic Victorian Government testing criteria but persistently swab negative. Results There were no significant differences in age, sex, Clinical Frailty Score (CFS) or Charlson Comorbidity Index (CCI) between 152 patients with COVID-19 and 118 patients with sCOVID. Similar results were found for 28-day mortality between patients with COVID-19 (35/152, 23%) and sCOVID (32/118, 27%) (P = 0.4). For the combined cohort, 28-day mortality was associated with initial oxygen saturation (P < 0.001), delirium (P < 0.001), hospital transfer for acuity (P = 0.02; but not public health/facility reasons), CFS (P = 0.04), prior ischaemic heart disease (P = 0.01) and dementia (P = 0.02). For patients with COVID-19, 28-day mortality was associated with initial oxygen saturation (P = 0.02), delirium (P < 0.001) and hospital transfer for acuity (P = 0.01), but not public health/facility reasons. Conclusion Unvaccinated aged care residents meeting COVID-19 testing criteria seen by InReach during a pandemic experience high mortality rates, including with negative swab result. Residents remaining within-facility (with InReach) experienced similar adjusted mortality odds to residents transferred to hospital for public health/facility-based reasons, and lower than those transferred for clinical acuity.