Mineral And Bone Disorder In Patients With Acute Kidney Injury Following Cardiac Surgery And Risk Of Adverse Outcomes

Objective: Acute kidney injury(AKI)is a common problem in serious patients and is associated with poor outcomes.Numerous studies have proved that chronic kidney disease-mineral and bone disorder(CKD-MBD)is associated with adverse outcomes,however,data in AKI is limited.Here we evaluated the association between mineral and bone metabolites and clinical outcomes among patients with AKI.Methods: We conducted a single-center,prospective,observational,cohort study in 158 patients who underwent cardiac surgery and developed AKI between June 2014 and January 2016.AKI definition is consistent with the criteria established by the KDIGO Work Group.Baseline characteristics were recorded and mineral and bone metabolites were measured preoperatively,AKI onset,and 5 days later.The primary endpoint was 28-day mortality,and secondary end point was progression to a higher AKI stage.Results: Enrollment intact parathyroid hormone(i PTH)correlated negatively with corrected calcium(r=-0.378,p<0.001)and positively with C-terminal FGF23(c FGF23)(r=0.334,p<0.001).Enrollment tartrate resistant acid phosphatase(TRACP-5b)correlated positively with 25-hydroxyvitamin D(r=0.189,p=0.018)and bone-specific alkaline phosphatase(r=0.179,p=0.025),c FGF23 correlated negatively with 25D(r=-0.162,p=0.042).Levels of corrected calcium(r=0.162,p=0.042),i PTH(r=0.177,p=0.026)and c FGF23(r=0.477,p<0.001)were positively associated with severity of AKI.Higher serum phosphate(HR 1.901,95%CI 1.144-3.157,p=0.013),TRACP-5b(HR 1.989,95%CI 1.020-3.877,p=0.044)and c FGF23(HR 2.274,95%CI 1.269-4.073,p=0.006)levels were all associated with 28-day mortality.Higher serum c FGF23 levels were a significantly risk of AKI progression(OR 1.647,95%CI 1.006-2.694,p<0.047).Conclusions: Among patients with AKI,mineral and bone metabolites are dysregulated.Higher levels of serum phosphate,TRACP-5b and c FGF23 are all associated with adverse outcomes.