Comparative Analysis of Renal Glomerular Filtration Rate Estimation Methods in Hypertensive Nigerians at Federal Medical Centre, Owerri

Accurate estimation of glomerular filtration rate is essential for detecting hypertension-related nephropathy, yet the optimal estimation equation for Nigerian populations has not been adequately validated. This study compared the performance of the Chronic Kidney Disease Epidemiology Collaboration, Modification of Diet in Renal Disease, and Cockcroft-Gault equations in estimating glomerular filtration rate among hypertensive Nigerians at Federal Medical Centre, Owerri, South East Nigeria. An analytical cross-sectional design enrolled 100 hypertensive adults. Serum creatinine was measured by the Jaffe method, and measured glomerular filtration rate was estimated from 24-hour urine creatinine clearance as a reference standard. The three prediction equations were applied and their outputs compared to the measured reference. Bland-Altman plots, intraclass correlation coefficients, and sensitivity analyses were performed. Results showed that the Chronic Kidney Disease Epidemiology Collaboration equation had the smallest mean bias and highest concordance with measured creatinine clearance in this population. The Cockcroft-Gault equation systematically overestimated filtration rate, particularly in obese individuals. The Modification of Diet in Renal Disease equation underestimated at lower filtration rates. This study addresses a critical methodological gap by generating population-specific performance data for filtration rate estimation in hypertensive South East Nigerians. The Chronic Kidney Disease Epidemiology Collaboration equation is recommended for clinical use in this setting, pending locally derived race-adjusted coefficients. Keywords: glomerular filtration rate, hypertension, nephropathy, creatinine clearance, Owerri.