Comparative predictive value of nine inflammation-derived haematological indices for 28-day mortality in patients with sepsis: a multicentre retrospective cohort study

The study examined nine inflammation-derived hematological indices calculated from routine blood tests for their ability to predict 28-day mortality in sepsis patients. The research included a development cohort of 26,512 sepsis patients from the MIMIC-IV database, of whom 2,669 died within 28 days, and an external validation cohort of 850 patients, of whom 182 died within 28 days. All nine indices were significantly associated with mortality, with neutrophil-to-lymphocyte ratio, neutrophil-to-platelet ratio, and monocyte-to-lymphocyte ratio showing the largest effects. However, individual indices had only limited ability to discriminate risk, and external validation did not confirm consistent associations. The study concludes that these indices should serve as supplementary markers alongside standard severity scores rather than as standalone mortality prediction tools.