Fibroblast growth factor 23 in acute myocardial infarction complicated by cardiogenic shock: a biomarker substudy of the intra-aortic balloon pump in cardiogenic shock II (IABP-SHOCK II) trial (Critical Care)

IntroductionCardiogenic shock (CS) is the leading cause of death in patients hospitalized with acute myocardial infarction (AMI). Biomarkers might help in risk stratification and understanding of pathophysiology. Preliminary data suggests that patients with CS face a profound increase in the osteocyte-derived hormone fibroblast growth factor 23 (FGF-23), which acts as a negative regulator of serum phosphate levels. The present study aimed to assess the predictive role of FGF-23 for clinical outcome in a large cohort of CS patients with and without renal dysfunction. Methods: In the randomized intra-aortic balloon pump in cardiogenic shock II (IABP-SHOCK II)-trial, 600 patients with CS complicating AMI were assigned to therapy with or without IABP. Our predefined biomarker substudy included 182 patients. Blood sampling was performed in a standardized procedure at three different time points (day 1 (day of admission), day 2 and day 3). Differences in outcome of patients with FGF-23 levels??median were compared by log-rank-testing. Stepwise logistic regression modeling was performed to identify predictors of death at 30 days and Cox-regression analysis for time to death during the first year. Results: At all three time points, non-survivors had significantly higher FGF-23 levels compared to survivors (P