Prevalence of Mildly Reduced Estimated GFR by Height- or Age-Related Equations in Young People With Obesity and Its Association with Cardiometabolic Risk Factors.

OBJECTIVE

To compare the prevalence of mildly reduced estimated glomerular filtration rate (MRGFR) (eGFR >60 and < 90 mL/min/1.73 m), calculated by two creatinine-based equations, and its association with cardiometabolic risk factors (CMRF) in youth with overweight (OW)/obesity (OB).

METHODS

This is a multicenter cross-sectional study involving university and non-university hospital pediatrics departments. We enrolled 3,118 youth with OW/OB (5-14 years) and 286 healthy normal weight (NW) youth. eGFR was calculated using bedside Schwartz equation (eGFRBSE) and Full Age Spectrum equation (eGFRFAS). In OW/OB group we analyzed the association between eGFR calculated by both equations and CMRF. Uric acid (UA) and birth weight were available in 2,135 and in 1,460 youth.

RESULTS

The prevalence of MRGFR was 3.8% in NW versus 7.8% in OW/OB (P = .016) by eGFRBSE, and 8.7% in NW versus 19.4% in OW/OB (P < .0001) by eGFRFAS. eGFRBSE and eGFRFAS identified 242 and 605 young people with OW/OB with MRGFR, respectively. Individuals with MRGFR according with both equations showed lower birth weight, younger age, higher BMI-SDS, non-high-density lipoprotein-cholesterol and UA as compared to those with normal eGFR. To examine whether the eGFRFAS was associated with a worse CMR profile also in the range of normal eGFRBSE, we reclassified young people with normal eGFRBSE (n = 2,876) according with eGFRFAS. Out of youth with normal eGFRBSE, 366 (12.7%) presented MRGFR by eGFRFAS and had lower age, higher BMI-SDS, BP and UA than the remaining youth reclassified as normal eGFRFAS.

CONCLUSION

MRGFR is associated with an altered CMR profile in a large sample of young people with overweight (OW)/obesity (OB). The eGFRFAS equation identifies a higher prevalence of youth with MRGFR, compared to eGFRBSE equation.