As of October 2021, about 242 million people around the world have been diagnosed with COVID-19, over 45 million of whom live in the U.S. Official sources estimate that between 25% and 30% of recovered COVID-19 patients suffer from lingering symptoms and related conditions that are collectively referred to as long COVID. Lingering symptoms that are commonly reported include fatigue, muscle and joint pain, breathing difficulties, and loss of taste and/or smell.

While kidney complications are now recognized as a common occurrence in acute COVID illness, they have not been linked to long-COVID syndrome until now. A large study recently published in the Journal of the American Society of Nephrology documents the startling prevalence of kidney disease among COVID-19 survivors more than 30 days post-infection. 

A Disturbing Discovery

The study involved 89,216 COVID-19 survivors and 1,637,467 non-infected participants. Researchers examined the risks of:

• Acute kidney injury (AKI) 
• Decline in kidney function, measured as estimated glomerular filtration rate (eGFR) 
• End-stage kidney disease (ESKD)
• Major adverse kidney events (MAKE), or an eGFR decline of 50% or more
• All-cause mortality 30 days or more after the acute infection

Outcomes concerning patient non-hospitalization, hospitalization, and admission to intensive care were also taken into account. The resulting data showed a marked increase in the risks of:

• AKI 
• eGFR decline
• ESKD
• A combination of eGFR decline of 50% or more, ESKD, and/or all-cause mortality

The rate of eGFR loss was associated with COVID infection severity, and was worse among those who were hospitalized and who developed AKI as part of their acute COVID infection.

The U.S. Needs to Prepare

Despite the fact that only U.S. men in the VA system were evaluated, the study findings are alarming and need to be addressed on both the clinical and policy levels. Appropriate kidney services and resources must be identified and made available across the country to accommodate those in need. Funding and care would have to be expanded considerably for those on dialysis and requiring organ transplants. Chronic kidney disease (CKD) stages 4 and 5 cost more than $45,000 each year in the U.S., and increase to more than $90,000 as patients transition to dialysis.

Two proposed courses of action include:

• Integrated multidisciplinary post-COVID clinics. Such clinics have already been established in parts of the U.S., Egypt, and Ireland, but they are time-consuming and potentially expensive to set up. 
• Artificial intelligence deep learning algorithms (DLA). These algorithms can be used to screen patients for CKD so that treatment can be initiated early and disease progression either slowed or halted.

Innovative solutions are needed to prepare for and manage the potential increase and substantial burden of kidney disease and failure resulting from long-COVID complications. The situation will continue to be monitored closely over the coming months.

*Singh, A. K. (2021, Oct. 5). CKD and Long-COVID Syndrome. Nephrology Times. https://www.docwirenews.com/nephtimes/nephtimes-features/nephtimes-columns/nephtimes-from-the-chair/ckd-and-the-long-covid-syndrome/