Fibroblast Growth factor 23 for prediction of outcome in community- acquired acute kidney injury: a prospective observational study

Abstract

Background Serum Fibroblast Growth factor 23 (FGF23) level has been found to be elevated in AKI through multiple previous studies. Moreover, higher FGF23 level was associated with mortality and adverse outcomes in critically ill patients and patients undergoing cardiac surgery who developed acute kidney injury (AKI) suggesting that FGF23 can have a prognostic value in AKI. The current study aims to investigate the association of serum FGF23 levels with morbidity and mortality in patients with community-acquired AKI. Methods A longitudinal prospective study was carried out that included 64 patients who presented with community-acquired AKI to Mansoura Nephrology and Dialysis Unit (MNDU) at Mansoura University Hospital. Serum intact FGF23 level was measured after admission. patients were followed up during hospital stay and then at 90-day after admission. The primary outcomes were hospital and 90-day mortality and renal recovery. Results In this study, nine of the studied 64 AKI patients (14.1%) died during hospital admission and 18 out of 62 AKI patients (29%) died during the 90-day follow up period including those who died during hospital admission. Hospital mortality was significantly higher in patients with shock, sepsis, hypoalbuminemia, or high FGF23 in univariate analysis (p < 0.05). However, when binary logistic regression was carried out, shock was the only significant independent predictor for mortality [p value = 0.015; adjusted odds ratio = 12.465], while serum FGF23 did not independently predict in-hospital [p value = 0.589; adjusted odds ratio = 1.001] or 90-day mortality [p value = 0.055; adjusted odds ratio = 1.003] when entered in the regression equation together with the other confounders. Serum FGF23 in this study was not also associated with renal recovery, need for renal replacement, or the duration from peak serum creatinine to renal recovery (p > 0.05). Conclusion This research showed that serum iFGF23 could not predict mortality, renal recovery, or need for renal replacement therapy in patients with community-acquired AKI.