COVID-19 Infections Result in Reduced eGFR

In new data presented during the 2022 American Society of Nephrology (ASN) Annual Meeting shows COVID-19 infections could result in a higher risk of reduced kidney function.

A team, led by Jordyn R. Thompson, the University of British Columbia, assessed how COVID-19 infections impact downstream kidney function using data from the BC Interdisciplinary COVID-19 Care Network.

Recent Research

Recently, investigators have found COVID-19 infections are linked to acute kidney dysfunction. However, the effect of COVID-19 infections on downstream kidney function has not previously been identified.

In the retrospective cohort study, the investigators identified 2212 adult patients with COVID-19 that were referred to the Post COVID Recovery Clinic (PCRC) in British Columbia between July 9, 2020 and April 21, 2022. The investigators used the COVID-19 diagnosis date as the index date.

The participants excluded had a history of kidney transplantation or dialysis prior to the index date, as well as patients who died within 3 months of the cohort entry.

The investigators obtained eGFR values from the Provincial Laboratory Information System and examined changed in eGFR at 3, 6, and 12 months following a COVID-19 infection among the same study participants using a linear mixed model.

Finally, they compared subgroup analysis between hospitalized patients and non-hospitalized patients and patients with diabetes with patients without diabetes.

The Patients

The study included 457 patients with a median age of 59 years. The prevalence of reduced eGFR, defined as ≤59ml/min/1.73m², was 16% at 3 months, compared to 16% at 6 months and 17% at 12 months post-index date.

The median eGFR at baseline was 90 (95% CI, 73-102), but was reduced to 85 (95% CI, 70-101) 6 months. This remained stable at 12 months post-index at 86 (95% CI, 69-101). The results from linear mixed model showed a 0.23 mL/min decrease in eGFR at each month following a COVID-19 infection (intercept, 85.51; slope, -0.23, P = 0.0003).

After conducting a subgroup analysis, the investigators found similar trends for decreasing eGFR over time in patients with diabetes (n = 188; intercept. 83.08; slope, -0.42; P = 0.0001) and non-diabetic patients (n = 269; intercept, 87.33; slope, -0.12; P = 0.13).

In addition, eGFR improved over time in non-hospitalized patients (n = 133; intercept, 88.34; slope, 0.24; P = 0.03) compared to a decreasing trend among hospitalized patients (n = 324; intercept, 83.94; slope, -0.41; P <0.001).

“One in 6 COVID-19 patients who were referred to PCRC had reduced eGFR. COVID-19 was associated with a statistically significant decrease in eGFR, particularly in diabetic & hospitalized patients that warrants ongoing monitoring following COVID-19 infection,” the authors wrote.

The study, “Long-Term Effect of COVID-19 Infection on Kidney Function Among COVID-19 Patients Followed in a Post-COVID-19 Recovery Clinic in British Columbia, Canada,” was published online by ASN.