Relation between Cockcroft-Gault, MDRD-4 and CKD-EPIformulas, compared with the 24-hour creatinin depuration: Correlación entre las fórmulas de medición de filtrado glomerular Cockcroft- Gault, MDRD-4 y CKD-EPI, y la depuración de creatinina de 24 horas

Abstract

Introduction:
It is currently evident that the population pyramid has undergone significant changes in recent times. The increase in the number of older adults brings with it new challenges at the medical level, such as the adaptation and adaptation of formulas and parameters that allow efficient and effective medical care to be provided. Among them, the determination of the glomerular filtration rate becomes a parameter of vital importance given its relationship with increased cardiovascular risk and general morbidity in this group of patients.

Objective:
To compare, in patients over 85 years without known chronic kidney disease, different formulas for calculating the glomerular filtration rate with diagnostic standard 24-hour creatinine clearance, in order to establish the best correlation between MDRD, CKD-EPI and Cockcroft-Gault.

Materials and methods:
A prospective, descriptive, cross-sectional observational study including 25 patients admitted to the Geriatrics service of the Juarez Hospital in Mexico, in the period from June 2017 to June 2018, serum creatinine levels were measured upon arrival, with 24-hour urine collection and performed filtering rate calculations with the CKDEPI, MDRD and Cockcroft Gault formulas.

Results:
The average glomerular filtration rate measured by creatinine clearance in 24 hours was 48.35 ml/min/1.73 m²; according to the formula of Cockcroft and Gault was 41.49 ml/min/1.73m², significantly lower than with MDRD and CKD-EPI 64.98 ml/min/1.73 m²-57.0/ml/min/1.73 m² respectively. There is a direct correlation between the different types of formulas; however, the one with the greatest statistical power and reciprocity is Cockcroft and Gault being statistically significant.

Conclusions:
In elderly patients, the formulas for the measurement of glomerular filtration rate are not interchangeable, showing an advantage for Cockcroft and Gault, being statistically significant (P < 0.05), however, it is necessary to perform more extensive studies in geriatric population, to have a more accurate estimate.