TNFRSF1A and diabetic kidney disease: Fernández-Real et al. [29] reported that elevated serum TNFR1, but not TNFR2, levels were associated with renal interstitial fibrosis in patients with type 2 diabetes and the early stage of diabetic nephropathy; however, this relationship was no longer significant after controlling for age, body mass index, or SBP.