Determining if the prognostic nutritional index can predict outcomes in community acquired bacterial pneumonia

The Prognostic Nutritional Index (PNI) uses albumin levels and total lymphocyte count to predict the relationship between immune-nutritional state and prognosis in a variety of diseases, however it has not been studied in community acquired bacterial pneumonia (CABP). We conducted a historical cohort study to determine if there was an association between PNI and clinical outcomes in patients with CABP.

We reviewed 204 adult patients with confirmed CABP, and calculated admission PNI and Neutrophil-to-Lymphocyte Ratio (NLR). A comparative analysis was performed to determine the association of these values, as well as other risk factors, with the primary outcomes of 30-day readmissions and death.

Of the 204 patients, 56.9% (116) were male, 48% (98) were black/African American and the mean age was 63.2 ± 16.1 years. The NLR was neither associated with death nor 30-day readmission. The mean PNI in those who survived was 34.7 ± 4.5, compared to 30.1 ± 6.5, in those who died, p < 0.001. From multivariable analysis after controlling for the Charlson score and age, every one-unit increase in the PNI decreased the risk of death by 13.6%. The PNI was not associated with readmissions.

These findings suggest that poor immune and nutritional states, as reflected by PNI, both contribute to mortality, with a significant negative correlation between PNI and death in CABP. PNI was predictive of mortality in this patient cohort; NLR was not. Monitoring of albumin and lymphocyte count in CABP can provide a means for prevention and early intervention.