GDF15 and chronic kidney disease: We first evaluate GDF15 concentration within several subgroups, including diabetes mellitus (no vs. yes), previous history of cardiovascular disease (no vs. yes), different CKD stages (CKD stage 1 + 2 group vs. 3 vs. 4 + 5) and uPCRs (uPCR <30mg/g vs. 30–300mg/g vs. >300mg/g).