Prognostic factors of poor outcomes in pneumonia in older adults: aspiration or frailty?

ABSTRACT

PURPOSE: Little is known about the long-term and functional prognoses of older adults with pneumonia, which complicates their management. There is a common belief that aspiration is a poor prognostic factor; however, the diagnosis of aspiration pneumonia (AP) lacks consensus criteria and is mainly based on clinical characteristics typical of the frailty syndrome. Therefore, the poor prognosis of AP may also be a result of frailty rather than aspiration. This study investigated the impact of AP and other prognostic factors in older patients with pneumonia. METHODS: We performed a retrospective cohort study of patients aged 75 years and older, admitted with pneumonia in 2021. We divided patients according to their initial diagnosis (AP or non-AP), compared outcomes using Kaplan-Meier curves, and used logistic regression to identify independent prognostic factors. RESULTS: 803 patients were included, with a median age of 84 years and 52.7% were male. 17.3% were initially diagnosed with AP. Mortality was significantly higher in those diagnosed with AP than non-AP during admission (27.6% vs 19.0%, p = 0.024) and at 1 year (64.2% vs 53.1%, p = 0.018), with survival analysis showing a median survival time of 62 days and 274 days in AP and non-AP, respectively (χ2 = 9.2, p = 0.002). However, the initial diagnosis of AP was not an independent risk factor for poor prognosis in multivariable analysis. Old age, frailty and cardio-respiratory comorbidities were the main factors associated with death. CONCLUSION: The greater mortality in AP may be a result of increased frailty rather than the diagnosis of aspiration itself. This supports our proposal for a paradigm shift from making predictions based on the potentially futile labelling of AP or non-AP, to considering frailty and overall condition of the patient.