eGFR Could Serve as Biomarker for Increased CVD Risk in Healthy Individuals

Remi Goupil, MD, MSc

New data from an analysis of patient data from the CARTaGENE biobank suggests increase estimated glomerular filtration rate (eGFR) may have value as a biomarker for increased cardiovascular risk in healthy individuals.

Using data from more than 20,000 individuals between the ages of 40-69 years, investigators found glomerular hyperfiltration was independently associated with increased cardiovascular risk in middle-aged healthy individuals—with the risk profile appearing similar to stage 3a chronic kidney disease.

In an effort to further characterize the cardiovascular associated with glomerular hyperfiltration in healthy individuals, a team of investigators—led by Remi Goupil, MD, of Université de Montréal—designed the prospective, longitudinal follow-up study using the CARTaGENE population cohort. In total, 20,004 individuals were selected for inclusion in the current study, all of which had data related to brachial blood pressure, central systolic blood pressure, and diastolic blood pressure.

All individuals included in the study were enrolled between August 2009 and October 2010. Of the 20,004 included, 9515 were considered healthy individuals, which investigators defined as the absence of hypertension, diabetes, cardiovascular disease, and eGFR less than 60 mL/min/1.73m2, or statin and/or aspirin use. The primary outcome measure of the study was cardiovascular events, which was a composite of cardiovascular mortality, myocardial infarction, unstable angina, heart failure requiring hospitalization, stroke, and transient ischemic attack.

Of the participants classified as healthy individuals, 473 had a glomerular hyperfiltration (median IQR eGFR, 112 [107-115] mL/min/1.73 m2) and 4761 had a normal glomerular filtration rate (control group; median IQR eGFR, 92 [87-97] mL/min/1.73 m2). Of note, individuals with glomerular hyperfiltration were slightly younger and more often African American or smokers when compared to those with normal glomerular filtration rate.

Over the follow-up period, which lasted a median of 70 months, 245 cardiovascular events occurred in the study population—3 instances of cardiovascular death, 67 myocardial infarctions, 69 unstable angina episodes, 52 heart failure episodes, 34 strokes, and 20 transient ischemic attacks. In the glomerular hyperfiltration groups, the incidence rates were 13.2 per 100 person-years compared to 7.7 per 100 person-years in the normal filtration group.

In adjusted and unadjusted analyses, glomerular hyperfiltration was associated with a higher risk of cardiovascular events compared to those with normal filtration (unadjusted HR, 1.71; 95% CI, 1.20-2.44; P = .003; aHR, 1.88; 95% CI, 1.30-2.74; P = .001). Investigators noted glomerular hyperfiltration remained significantly associated with cardiovascular events even after stratification for age decade, sex, race, smoking status, and obesity. Additionally, glomerular hyperfiltration remained significantly associated with cardiovascular events after exclusion of participants with cardiovascular events in the first 6 months (HR, 2.04; 95% CI, 1.39-2.99; P <.001), first 12 months (HR, 2.03; 95% CI, 1.35-3.06; P=.001), and after exclusion of ischemic attack from the composite outcome (HR, 2.03; 95% CI, 1.39-2.97; P <.001).

An additional analysis performed by investigators compared 406 propensity-matched healthy individuals with glomerular hyperfiltration and 406 controls. Results of this analysis indicated those with glomerular hyperfiltration had median IQR eGFR of 112 (106-115) mL/min/ 1.73m2 compared with 94 (88-99) mL/min/1.73m2 among controls. Unadjusted regression analysis indicated glomerular hyperfiltration was associated with higher cardiovascular events risk compared to those with normal filtration rate (HR, 2.20; 95% CI, 1.44-4.24; P = .02).

In a comparison of 597 individuals with stage 3a CKD, investigators noted results indicated healthy individuals with glomerular hyperfiltration had a cardiovascular events risk similar to participants with stage 3a CKD (HR, 0.90; 95% CI, 0.56-1.42; P = .64).

This study, “Association of Glomerular Hyperfiltration and Cardiovascular Risk in Middle-Aged Healthy Individuals,” was published in JAMA Network Open.