Elevated Neopterin Levels Predict Early Death in Older Hip-fracture Patients

Abstract

Our society faces a major challenge concerning management of the health and socio-economic burden caused by acute physical stress in the older population (+75 years). In particular, hip-fracture surgery (HFS) represents a major health care preoccupation, affecting 1.6 million patients worldwide, resulting in a significant drop in life quality and autonomy. The trauma is associated with 20–30% one-year mortality in the elderly. In the present study, we aim to identify factors, which influence and/or predict the outcome of elderly hip- fracture patients (HFP) post-surgery. Our objective was to identify biomarkers with a prognostic capacity of one-year mortality. We employed an observational cohort of HFP (n = 60) followed-up longitudinally during the first year post fracture. Clinical and biological data (n = 136), collected at arrival to hospital, were then compared to healthy controls (n = 42) and analyzed using a regularized logistic regression model with lasso penalty followed by 10-fold cross-validation of variables. We show that plasmatic neopterin levels, a molecule released by IFN-γ-activated macrophages, is predictive of mortality in HFP (ROC-AUC = 0.859). Moreover, neopterin measured at arrival to the hospital correlated negatively with the time of survival after HFS. Neopterin therefore represents a biomarker, which enables better follow-up of patients at risk of early death.

Keywords

• Hip-fracture
• Inflammation
• Clinical outcome
• Biomarker
• Aging