Glomerular Filtration Rate in Sick Elderly Inpatients

Abstract

The glomerular filtration rate was measured in the sick elderly patients using the single shot 51Cr EDTA method. As would be expected, such patients have worse renal function than the fit elderly. The filtration rate can be usefully predicted from either blood urea or serum creatinine, but a superior prediction is obtained when these factors are combined using a formula derived from multiple regression analysis.

Value of Admission Profile Tests for Prognosis in Elderly Patients

“…The finding that blood urea concentration is a significant predictor in both sexes was to be expected. Urea is the best single index of renal function in elderly patients (13), and renal failure was an important cause of death in the geriatric patients studied. Furthermore, urea concentration is an indicator of dehydration, which is a common accompaniment of severe illness in old age.…”

“…High sodium and hemoglobin values may share this possible role with urea as indicators of dehydration, and thus of the severity of constitutional illness. The eclipse of phosphate and bicarbonate (the other indices of renal function included in the study) by urea may thus be explained by their inferiority as predictors of renal function (13) together with their inability to indicate dehydration.…”