Chronic kidney disease is increasingly recognized as a significant global health concern, impacting approximately 10−15% of adults worldwide. Projections indicate that by 2040, it could become one of the top five causes of years of life lost. A critical obstacle in addressing this issue is the insufficient screening practices, with many individuals receiving a diagnosis only after experiencing substantial loss of kidney function, thereby limiting treatment options.
Revolutionizing Kidney Function Assessment
To tackle this challenge, researchers have created population-based reference charts for estimating glomerular filtration rate (eGFR), the primary metric for evaluating kidney health. Rather than depending on a fixed cutoff, these charts provide a comparative analysis of an individual's kidney function against peers of the same age and gender. This innovative method aims to assist healthcare providers in identifying elevated risks at an earlier stage, enabling proactive measures.
"Our inspiration stemmed from the growth and weight charts utilized in pediatrics, which effectively aid clinicians in spotting children who may be at risk for obesity or growth issues," explains Yuanhang Yang, the lead author and postdoctoral researcher at the Department of Clinical Science and Education, Södersjukhuset, Karolinska Institutet.
Online Calculator for Healthcare Professionals
The research team has made the eGFR distribution charts accessible to healthcare practitioners and developed an online calculator that indicates a patient's standing within age-specific population norms. This tool, crafted by PhD student Antoine Creon, is designed to enhance clinical decision-making during routine evaluations.
The study utilized health data from over 1.1 million adults in Stockholm, representing around 80% of residents aged between 40 and 100. Nearly seven million eGFR test results collected from 2006 to 2021 were analyzed to create comprehensive distributions based on age and gender.
Lower Percentiles Associated with Adverse Outcomes
The findings reveal that kidney function levels significantly deviating from the median for an individual's age and sex correlate with worse health outcomes. Those whose eGFR fell below the 25th percentile faced a considerably higher risk of advancing to kidney failure requiring dialysis or transplantation. Additionally, a U-shaped mortality pattern was observed, indicating that both unusually low and high eGFR percentiles were linked to increased mortality risk.
Identifying Missed Opportunities for Early Intervention
The results also shed light on deficiencies in current clinical practices. Among individuals with an eGFR above 60 ml/min/1.73 m², yet below the 25th percentile for their age, only 25% had undergone further testing for urinary albumin, a crucial assessment for detecting early kidney damage and facilitating timely intervention.
"For instance, a 55-year-old woman with an eGFR of 80 might not raise concerns for most clinicians. However, our charts indicate that this value corresponds to the 10th percentile for her age group, suggesting she has a threefold increased risk of requiring dialysis in the future. This highlights a significant opportunity for earlier action," notes Juan Jesús Carrero, a professor at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet.
Research Context and Support
This study is part of the SCREAM project and has received funding from various organizations, including the Swedish Research Council, the Swedish Heart-Lung Foundation, Region Stockholm, and the Swedish Kidney Foundation. The researchers declare no conflicts of interest regarding the study's content.
