Hospitalization of very old critically ill patients in medical intermediate care units in France: a nationwide population-based study

As the trajectory of very old critically-ill patients becomes an increasingly significant global challenge, these patients are often referred to intermediate care units. Intermediate care units provide a level of care that is less intensive than the intensive care unit (ICU) but more advanced than standard hospital wards. We aimed to assess the nationwide utilization of intermediate care units for critically ill patients aged 80 years or older (≥ 80 y.o.) and to examine their characteristics and long-term mortality outcomes.

From the overall adult population (aged 18 years and older) hospitalized in France (French Hospital Discharge Database) from January 1, 2014, to December 31, 2022, patients ≥ 80 y.o. were included. We examined trends in the utilization of medical intermediate care units for critically ill patients ≥ 80 y.o and reported patient characteristics, including the Charlson comorbidity index and Hospital Frailty Risk Score. Readmission rates (hospital or rehabilitation unit) and mortality rates were calculated during a one-year follow-up period after the end of hospital stay.

The proportion of patients ≥ 80 y.o. in intermediate care units was 31% whereas it was 17% in ICU. Patients with greater comorbidities and severity were more frequently hospitalized in polyvalent intermediate care units (10% of them receiving acute organ support) compared to specialized intermediate care units. Admission to intermediate care units was associated with a 14% mortality rate during the stay, 28% at one year. Additionally, 58% of intermediate care units patients were rehospitalized within the year following discharge (6% in critical care units).

One-third of the patients hospitalized in the intermediate care units in France are aged 80 years or older.