Our study results suggested the trend that the subjects with the C allele of PPARD T-842C polymorphism were at an increased risk of CKD, which was in line with our hypothesis considering that the PPARD T-842C polymorphism found to be significantly associated with the risk of CKD in the present study is in tight linkage disequilibrium with other functional polymorphisms in PPARD gene, PPARD T294C (rs2016520) (D′ = 1.00 and r2 = 0.81 in Japanese [JPT]) [32]. Here, PPARD is linked to chronic kidney disease.