IL6 and susceptibility to pneumonia measurement: The levels of IL-6, procalcitonin, sRAGE, and angiopoietin-2 were lower post-event compared to the day of pneumonia diagnosis, while syndecan-1 and angiopoietin-1 concentrations were higher post-event; the other host response biomarkers remained unaltered (Additional file 1: Figs. S5 and S6).