Contribution of clinical severity and geriatric risk factors in predicting short-term mortality of older hospitalized pneumonia patients: the Pneumonia in Italian Acute Care for Elderly units (PIACE) study

Background Clinical severity of pneumonia in older persons increases the risk for short-term mortality. Comprehensive geriatric assessment (CGA) may provide further insight in prognostic stratification. Aims To investigate whether CGA may improve prognostic stratification among older patients with pneumonia admitted to hospital. Methods Our series consisted of 318 consecutive patients hospitalized for pneumonia in a multicenter observational study. Disease severity was assessed by Sequential Organ Failure Assessment (SOFA) and Pneumonia Severity Index (PSI). CGA included the occurrence of delirium, Basic Activities of Daily Living (BADL) disability, cognitive impairment at Short Portable Mental Status Questionnaire (SPMSQ) and overall comorbidity assessed by Cumulative Illness Rating Scale (CIRS). The outcomes were in-hospital and post-discharge 3 month mortality. Statistical analysis was carried out by Cox regression, area under receiver operating curve (AUC) and net reclassification index (NRI). Results Overall, 53 patients died during hospitalization and 52 after discharge. Delirium, SOFA score and admission BADL disability were significant predictors of in-hospital mortality. SOFA score, CIRS, previous long-term oxygen therapy and discharge BADL dependency significantly predicted post-discharge mortality. The accuracy of SOFA in predicting in-hospital and post-discharge mortality was fair (AUC = 0.685, 95% CI = 0.610-0.761 and AUC = 0.663, 95% CI = 0.593-0.734, respectively). BADL dependency and delirium improved predictive accuracy for in-hospital mortality (Delta AUC = 0.144, 95% CI = 0.062-0.227, p < 0.001), while pre-admission oxygen therapy, CIRS and BADL dependency improved predictivity for 3 month mortality (Delta AUC = 0.177, 95% CI = 0.102-0.252, p < 0.001). Discussion Among older pneumonia patients, prognostic stratification obtained by clinical severity indexes is significantly improved by CGA risk factors. Conclusions CGA provides important information for prognostic stratification and clinical management of older pneumonia patients.