FGF21 and kidney disorder: Circulating biomarkers such as IL-6, IL-10, CD163, CXCL9, CCL22, GDF15, IL-33, FGF21, follistatin, and neurofilament light chain (NfL) have been associated with both microvascular and macrovascular complications, including neuropathy, nephropathy, retinopathy, and major adverse cardiovascular events (MACE) [319].