Endocrine Abstracts

Introduction: Fibroblast growth factor-21 (FGF-21) is a recently discovered hormone acting as a central regulator of metabolism via adaptation of glucose homeostasis, insulin sensitivity, and ketogenesis. While acute systemic inflammatory conditions come along with profound alterations of metabolism, the role of FGF-21 in these acute phase responses is still unknown.

Methods: This is a secondary analysis of two randomized, controlled trials in patients presenting to the emergency department with community-acquired pneumonia. Multivariate regression models were performed to analyze associations of FGF-21 with disease severity, mortality, length of hospital stay and duration of antibiotic treatment.

Results: A total of 509 patients were included in the analysis, 150 patients from the ProCAP trial and 359 from the STEP trial. Serum FGF-21 on admission was significantly correlated to disease severity as measured by pneumonia severity index (R²=0.159, P<0.0001). FGF-21 levels at admission were associated with reduced likelihood of clinical stability, adjusted hazard ratio (HR) 0.88 (95% CI, 0.81–0.96; P=0.006) and consecutively prolonged duration of intravenous antibiotic therapy (adjusted HR 0.56; 95% CI, 0.15–0.97; P=0.008). FGF-21 levels were higher at admission in nonsurvivors than in survivors (median 1307.6 vs 416.7 pg/ml; P<0.001), yielding a 1.41-fold increased adjusted odds ratio of 30-day mortality (95% CI, 1.05–1.90; P=0.02). FGF-21 was found to identify patients for 30-day mortality with superior discriminative power (AUC 0.74) compared to procalcitonin (AUC 0.62) or c-reactive protein (AUC 0.48).

Discussion: FGF-21 was markedly increased in patients with community-acquired pneumonia and was found to identify patients at risk for adverse outcome more effectively than routine diagnostic markers.