Variability in eGFR and the Risk of Adverse Kidney Outcomes and All-Cause Mortality: A Retrospective Observational...

Area of Science:

• Nephrology
• Primary Care Medicine
• Biostatistics

Background:

• Estimated glomerular filtration rate (eGFR) variability is linked to adverse health events, but its role in kidney disease progression in primary care is unclear.
• Understanding eGFR variability's impact is crucial for managing chronic kidney disease (CKD) and preventing adverse outcomes.

Purpose of the Study:

• To investigate the association between eGFR variability and kidney composite endpoints in a large primary care population.
• To determine if eGFR variability can serve as an independent predictor of adverse kidney outcomes.

Main Methods:

• Retrospective cohort study using longitudinal eGFR data from the MedicineInsight database (2011-2018).
• Included adults (≥18 years) with ≥3 eGFR measurements over 3 years.
• eGFR variability assessed by coefficient of variation (CV); kidney composite endpoint included sustained eGFR decline, low eGFR, and all-cause mortality.

Main Results:

• Higher eGFR variability significantly increased the risk of the kidney composite endpoint (HR: 2.17; 95% CI: 2.03-2.32) in the highest vs. lowest quintile.
• This association remained significant after adjusting for mean eGFR, eGFR slope, cardiovascular risk factors, and medication use.
• Consistent trends observed across subgroups, including age, sex, hypertension, diabetes, and baseline eGFR.

Conclusions:

• Increased eGFR variability is an independent predictor of adverse kidney outcomes.
• eGFR variability shows promise as a clinical biomarker for identifying high-risk patients in primary care.
• Routine assessment of eGFR variability may enhance risk stratification and timely interventions for kidney disease.