Use of a frailty index based upon routine laboratory data to predict complication and mortality in older community-acquired pneumonia patients

Community-acquired pneumonia (CAP) is a common and potentially deadly infection that often arises in older adults. However, the relevance of frailty assessments in older CAP patients remains to be established. The present study was designed to assess the value of a pretreatment frailty index based upon routine laboratory parameters as a predictor of complication and mortality among older CAP patients.

Design: Retrospective cohort study.

One of the teaching hospitals in western China. Hospitalized CAP patients ≥ 60 years of age. Relevant data were gathered from medical records, local government mortality databases, and telephone interviews. Analyzed outcomes included complication (including respiratory failure and septic shock) and all-cause mortality. A frailty index was constructed based upon 44 pre-treatment laboratory parameters (FI-LAB), and then three cut-off values were selected to define individuals that were robust (0.0-0.2), pre-frail (0.2-0.35), and frail (≥0.35).

In total, this study incorporated 627 patients (60.77% male; median age: 80 years). Rates of respiratory failure, septic shock and death were higher for frail and prefrail individuals relative to robust individuals (30.13% vs 21.13% vs 6.59%, p < 0.001; 40.38% vs 15.02% vs 3.88%, p < 0.001; 73.08% vs 54.93% vs 24.42%, p < 0.001). Following adjustment for potential confounders, both the pre-frail and frail groups exhibited elevated risk of respiratory failure (OR = 3.326, 95%CI: 1.799-6.15; OR = 5.353, 95%CI: 2.835-10.107), higher risk of septic shock (OR = 3.701, 95%CI: 1.736-7.889; OR = 12.713, 95%CI: 6.112-26.445), and a higher risk of death (HR = 2.173, 95%CI: 1.576-2.996; HR = 2.877, 95%CI: 2.026-4.083) than the robust group.

Frailty, as defined using a scale based upon routine laboratory parameters, can predict a higher risk of complication and mortality in older CAP patients.