Simple method can enable early detection and prevention of chronic kidney disease

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Subtle abnormalities in kidney function—even within the range considered normal—may help identify people at risk of developing chronic kidney disease. This is shown in a new study from Karolinska Institutet, published in Kidney International. The researchers have therefore developed a web-based tool that could aid in early detection and thus primary prevention.

Chronic kidney disease is a growing global health concern afflicting 10–15% of adults worldwide and is projected to become one of the top five leading causes of years of life lost by 2040.

In the absence of effective screening programs, patients are often diagnosed late, when more than half of their kidney function has already been lost.

To address this gap, researchers at Karolinska Institutet have constructed population-based distributions for estimated glomerular filtration rate (eGFR)—the most widely used measure of kidney function. The aim is to help doctors identify people at risk, thus enabling early preventive action.

“We were inspired by the growth and weight charts used in pediatrics, which intuitively help clinicians identify children at risk of obesity or undergrowth,” says the first author of the study, Yuanhang Yang, postdoctoral researcher at the Department of Clinical Science and Education, Södersjukhuset, Karolinska Institutet.

Web-based calculator for health care professionals

The researchers have made their eGFR distribution charts openly available to health care professionals and developed a web-based calculator, developed by Ph.D. student Antoine Creon, that can help assess how a patient’s eGFR compares with population norms for their age.

The study included over 1.1 million adults in the region of Stockholm, Sweden, covering roughly 80% of the population aged between 40 and 100 years. Nearly seven million eGFR tests collected between 2006 and 2021 were used to construct age- and sex-specific distributions.

The findings show that departures from the median eGFR for one’s age and sex are associated with worse outcomes. Individuals with an eGFR below the 25th percentile had a markedly higher risk of developing kidney failure requiring dialysis or transplantation. Mortality also displayed a U-shaped relationship; both low and high percentile extremes were linked to increased risk of death.

Ability to act earlier

The study also illustrates this lack of awareness in health care, according to the researchers. Among those with a seemingly normal eGFR above 60 ml/min/1.73 m², but below the 25th percentile, only one fourth had received additional testing for urinary albumin, which is important for detecting early kidney damage.

“For example, consider a 55-year-old woman with an eGFR of 80. Most clinicians would not react to such a seemingly normal value. However, our charts show that this corresponds to the 10th percentile for women of that age, and that she has a three-fold higher risk of starting dialysis in the future. This signals an opportunity to act earlier,” says Juan Jesús Carrero, professor at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet.