Estimated Glomerular Filtration Rate (Egfr) In Elderly: A Comparison Between The Ckd-Epicreatinine And Biscreatinine Equations / Taxa da filtração glomerular estimada (tfge) em idosos: Comparação entre as equações ckd-epi-creatinina e bis-creatinina

Abstract

Background: Aging is a risk factor for the development of chronic kidney disease (CKD). The estimation of the glomerular filtration rate (eGFR) is the most used method to assess renal function, influencing individualized therapeutic adjustment of medications eliminated by the kidneys. Objective: To compare the results obtained using two creatinine-based equations applied in older people: CKD-EPICreatinine and BISCreatinine; as well as evaluate the impact of these equations in the classification of the elderly in different stages of CKD. Materials and methods: An observational study was carried out in a long-term care facility, including subjects aged 70 years or older. Renal function was assessed by two equations: CKD-EPICreatinine and BISCreatinine. Statistical analysis included Kolmogorov-Smirnov, Wilcoxon, Spearman, and Bland-Altman tests. Staging of the level of renal function was performed according to the Kidney Disease: Improving Global Outcomes guidelines. Results: 73 patients with a mean age of 79.2 ± 6.1 years were evaluated. There was a significant decrease (p<0.001) in the eGFR obtained by the BISCreatinine equation in relation to CKD-EPICreatinine. Both equations showed strong correlation (r=0.96, p<0.001). The concordance analysis it was observed a bias of -13.6% (-33.5 to 6.3). From the mild-moderate reduction in renal function (3a stage), there was an increase in the number of elderly people classified in more advanced stages when assessed by BISCreatinine. Conclusion: BISCreatinine has been shown to underestimate the eGFR results, not showing full agreement from a clinical point of view for stratification of renal function with CKD-EPICreatinine in eGFR greater than 59 ml/min x 1,73m2