Increased Vulnerability to COVID-19 in Chronic Kidney Disease

Background: The significance of chronic kidney disease on susceptibility to COVID-19 and subsequent outcomes remains unaddressed.

Objective: To investigate the association of estimated glomerular filtration rate (eGFR) on risk of contracting COVID-19 and subsequent adverse outcomes.

Methods: Rates of hospital-diagnosed COVID-19 were compared across strata of eGFR based on conditional logistic regression using a nested case-control framework with 1:4 matching of patients diagnosed with COVID-19 with controls from the Danish general population on age, gender, diabetes and hypertension. Risk of subsequent severe COVID-19 or death was assessed in a cohort study with comparisons across strata of eGFR based on adjusted Cox regression models with G-computation of results to determine 60-day risk standardized to the distribution of risk factors in the sample.

Results: Estimated glomerular filtration rate was inversely associated with rate of hospital-diagnosed COVID-19: eGFR 61-90 mL/min/1.73m HR 1.13 (95% CI 1.03-1.25), P = 0.011; eGFR 46-60 mL/min/1.73m   HR 1.26 (95% CI 1.06-1.50), P = 0.008; eGFR 31-45 mL/min/1.73m HR 1.68 (95% CI 1.34-2.11), P < 0.001; and eGFR ≤ 30 mL/min/1.73m 3.33 (95% CI 2.50-4.42), P < 0.001 (eGFR > 90 mL/min/1.73m as reference), and renal impairment was associated with progressive increase in standardized 60-day risk of death or severe COVID-19; eGFR > 90 mL/min/1.73m 13.9% (95% CI 9.7-15.0); eGFR 90-61 mL/min/1.73m 16.1% (95% CI 14.5-17.7); eGFR 46-60 mL/min/1.73m 17.8% (95% CI 14.7-21.2); eGFR 31-45 mL/min/1.73m 22.6% (95% CI 18.2-26.2); and eGFR ≤ 30 mL/min/1.73m 23.6% (95% CI 18.1-29.1).

Conclusions: Renal insufficiency was associated with progressive increase in both rate of hospital-diagnosed COVID-19 and subsequent risk of adverse outcomes. Results underscore a possible vulnerability associated with impaired renal function in relation to COVID-19.