SPP1 and chronic kidney disease: Meta-analysis revealed that increasing OPN (SMD = 5.52, 95% CI = 1.59-9.44, p = 0.01) and KIM-1 (SMD = 1.45, 95% CI = 0.50-2.39, p = 0.0027), as well as decreasing Fetuin-A level (SMD = -1.31, 95% CI = -2.37 - -0.26, p = 0.01) were significant in CKD patients with ESRD.