A comprehensive analysis of data from the Stockholm Creatinine Measurements (SCREAM) Project has revealed that COVID-19 infection leads to a more significant decline in kidney function compared to other respiratory infections, particularly in hospitalized patients.
The study, led by Viyaasan Mahalingasivam, MPhil, from Barts Health NHS Trust, examined data from over 70,000 patients between February 2018 and January 2022. The research team found that COVID-19 infection accelerated the decline in estimated glomerular filtration rate (eGFR) by 4.1 mL/min/1.73m2, substantially more than observed with pneumonia.
Impact on Hospitalized Patients
The findings were particularly striking among hospitalized patients. Of the 34,565 COVID-19 patients studied, 13.3% required hospitalization, with 19% of these cases developing acute kidney injury (AKI). The research showed that hospitalized COVID-19 patients experienced a more severe decline in kidney function:
- 5.0 mL/min/1.73m2 faster decline in hospitalized COVID-19 patients
- 3.2 mL/min/1.73m2 faster decline in non-hospitalized COVID-19 patients
- 5.4% annual reduction in eGFR among hospitalized cases after adjustment for covariates
Comparison with Pneumonia
The study provided valuable comparative data between COVID-19 and pneumonia patients:
- 35,987 pneumonia patients were analyzed
- 46.5% of pneumonia patients required hospitalization
- Pneumonia patients showed only a 0.9 mL/min/1.73m2 faster decline in kidney function
- After adjustment, pneumonia cases demonstrated a 2.3% annual reduction in eGFR
Clinical Implications
"SARS-CoV-2 may directly or indirectly affect the kidney, with acute kidney injury observed in approximately 30% of COVID-19 hospitalizations," noted Mahalingasivam and colleagues. The research team emphasized that these findings underscore the importance of careful monitoring of kidney function in COVID-19 patients, particularly those requiring hospitalization.
Study Methodology and Limitations
The research team utilized the 2009 CKD-EPI equation without ethnicity adjustment to calculate eGFR. The study population included adults with at least one eGFR measurement in the two years prior to their COVID-19 or pneumonia diagnosis.
Several limitations were noted, including:
- Observational study design
- Lack of data on ethnicity and body mass index
- Limited follow-up duration
- Potential misclassification of infection severity
Recommendations for Clinical Practice
Based on these findings, the researchers strongly recommend implementing closer monitoring protocols for kidney function in patients hospitalized with COVID-19. This enhanced surveillance aims to ensure early detection and optimal management of chronic kidney disease, potentially preventing complications and further functional decline.
