Early osteopontin levels predict mortality in patients with septic shock

Background: Inflammatory biomarkers could be useful to stratify the risk of sepsis adverse outcome and potentially improving the clinical management. Here, we investigated the prognostic role of the inflammatory molecule osteopontin (OPN) in patients with severe sepsis with and without septic shock. Material and methods: This is a sub-analysis of 957 patients with sepsis/septic shock from the Albumin Italian Outcome Sepsis (ALBIOS) study. Alongside demographic, clinical, and laboratory data, we assessed plasmatic values of OPN at day 1, 2 and 7 after enrolment. The primary outcome was the predictive role of OPN values at day 1on death for any cause at 28 days after enrolment. Results: Plasma OPN values at day 1 were higher in patients with septic shock and correlated with the severity of multi-organ dysfunction. Once categorized for 28-day mortality, survivors were characterized by lower OPN levels at each time point and statistically significant drop overtime (p<0.001 for all). Similarly, OPN reduction during the first 7 days was associated with reduced hospitalization and mortality overtime. Multivariate logistic and Cox regression models confirmed plasma OPN at day 1 as predictor of both 28- and 90-day mortality and infection resolution as well, independently of demographic, clinical and therapeutic variables. However, this prognostic value was limited to septic shock patients. Conclusions: In patients with septic shock, OPN plasma levels at day 1 predict a poor clinical outcome. These results provide the rationale for future pathophysiological studies aimed at clarifying the mechanisms triggered by OPN in septic shock (ALBIOS ClinicalTrials.gov Identifier: NCT00707122).