Presentation, management, and outcomes of older compared to younger adults with hospital‑acquired bloodstream infections in the intensive care unit: a multicenter cohort study

Abstract

Purpose. Older adults admitted to the intensive care unit (ICU) usually have fair baseline functional capacity, yet their age and frailty may compromise their management. We compared the characteristics and management of older (≥75 years) versus younger adults hospitalized in ICU with hospital-acquired bloodstream infection (HA-BSI). Methods. Nested cohort study within the EUROBACT-2 database, a multinational prospective cohort study including adults (≥18 years) hospitalized in the ICU during 2019–2021. We compared older versus younger adults in terms of infection characteristics (clinical signs and symptoms, source, and microbiological data), management (imaging, source control, antimicrobial therapy), and outcomes (28-day mortality and hospital discharge). Results. Among 2111 individuals hospitalized in 219 ICUs with HA-BSI, 563 (27%) were≥75 years old. Compared to younger patients, these individuals had higher comorbidity score and lower functional capacity; presented more often with a pulmonary, urinary, or unknown HA-BSI source; and had lower heart rate, blood pressure and temperature at presentation. Pathogens and resistance rates were similar in both groups. Diferences in management included mainly lower rates of efective source control achievement among aged individuals. Older adults also had signifcantly higher day-28 mortality (50% versus 34%, p<0.001), and lower rates of discharge from hospital (12% versus 20%, p<0.001) by this time. Conclusions. Older adults with HA-BSI hospitalized in ICU have diferent baseline characteristics and source of infection compared to younger patients. Management of older adults difers mainly by lower probability to achieve source control. This should be targeted to improve outcomes among older ICU patients.