Pehuen Fernandez
Hospital Privado de Cordoba, Argentina
Title: Estimated glomerular filtration in obese patients
Biography
Biography: Pehuen Fernandez
Abstract
Introduction: Estimating glomerular filtration rate (GFR) in obese subjects is a challenge. An analysis is made from the performance of equations to estimate GFR in this population.
Materials & Method: This cross-sectional study included 100 obese subjects evaluated between 2008 and 2015. The GFR was measured with urinary iothalamate clearence (reference standard) and estimated using creatinine-based formulas: Cockroft Gault, MDRD, CKD-EPI, MCQ and CKD-MCQ (mean of these). A global performance score (G-P-Score) was created to unify all the analysis criteria.
Results: CKD-MCQ equation had the best performance in obesity grade I (n=53) [bias=1.6 +/- 17.4 ml/min × 1.73 m2; correlation (r)=0.87; area under the curve (AUC)=0.978; sensitivity (S) =100%; specificity (E)=87.8%]. MCQ and CKD-MCQ had the lowest bias in obesity grade II (n=25) (bias=1.8 +/- 22.3 and -4.4 +/- 21.9 ml/min × 1.73m2) and CKD-MCQ the highest r (r=0.89), with the same AUC, S, and E (AUC=0.976, S=85.7%, E=100%). MDRD equation had the lowest bias in obesity grade III (n=22) (bias=-0.2 +/- 31.1 ml/min × 1.73 m2), and CKD-MCQ had the highest r and AUC (r=0.66, AUC=0.929), with the same S and E (S=80%, E=94.1%) than MDRD. CKD-MCQ was the only equation without significant differences compared to the reference standard in any of the obesity levels. The highest score was obtained in the G-P-score (39/48).
Conclusion: CKD-MCQ had the better overall performance for estimating GFR in subjects with different degrees of obesity.