TNFRSF1A and chronic kidney disease: However, in this study, the relationship between TNFRs and eGFR was not as strong (TNFR1, r = 0.47; TNFR2, r = 0.44) as in our previous reports in patients with diabetes and CKD [26], indicating that elevated TNFR levels in COVID-19 patients cannot be adequately explained by reduced eGFR alone.