Cytokine levels predict 30-day mortality in octogenarians and nonagenarians with community-acquired pneumonia: a retrospective observational study

To analyze the value of cytokines (tumor necrosis factor [TNF]-α, interleukin [IL]-1β, IL-6, IL-8, IL-10) as predictors of mortality at 30 days in octogenarians and nonagenarians hospitalized in an internal medicine unit for community-acquired pneumonia (CAP). An observational, analytical, retrospective cohort study was conducted in the Department of Internal Medicine at Alicante General University Hospital between January 2014 and December 2015. Blood samples were frozen at - 80 °C, and cytokines were measured by ELISA. We included 115 patients, of whom 54% were men, with a mean age of 86.4 (standard deviation 4.5) years. There is a moderate correlation between IL-10 levels and CURB-65 score (p < 0.001) and a weak correlation with creatinine levels (p = 0.012) and urea levels (p = 0.032). Forty-five (39.1%) patients died within 30 days. In a multivariate analysis, the variables associated with mortality at 30 days were the following: age (adjusted odds ratio [ORa] 1.134, 95% confidence interval [CI] 1.02, 1.26), male sex (ORa 2.85, 95% CI 1.14, 7.14), IL-8 of 19 pg/mL or more (ORa 4.09, 95% CI 1.67, 10.01), and IL-10 of 11.29 pg/mL or more (ORa 4.00, 95% CI 1.58, 10.12). High IL-8 and IL-10 levels were shown to predict 30-day mortality in elderly patients with CAP. The inflammatory response in these patients seems to condition their prognosis. Further research in this line would provide more understanding about the physiopathological mechanisms and potential therapeutic targets for improving survival.