Browsing by Author "Huidobro E J.P."

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    A new equation to estimate daily natriuresis from parameters in plasma and spot urine sample in the Chilean populationNueva ecuación para la estimación de la natriuresis diaria a partir de parámetros en plasma y orina aislada en población chilena
    (HUMANA PRESS INC, 2021) Sepúlveda R.A.; Huidobro E J.P.; Jara A.; Tagle R.
    BACKGROUND: Excessive sodium intake is associated with increased cardiovascular morbidity and mortality. Daily sodium intake is usually inferred from sodium excretion in a 24-hour urine collection, which is cumbersome and prone to errors. Different formulas have attempted to estimate 24-hour urinary sodium from a spot urine sample. Unfortunately, their concordances are insufficient and have not been tested in our population. AIM: To develop an equation to predict 24-hour urine sodium from parameters in plasma and spot urine samples. To validate the equation and compare it with other formulas in Chilean population. MATERIAL AND METHODS: Analysis of 24-hour urine collections, plasma sample and spot urine sample from 174 adult outpatients (81% females) with an estimated glomerular filtration rate (eGFR) ≥ 60 mL/min/1.73m2. These were collected between 2015 and 2019 using standardized methods and educating patients about the correct method to collect 24 h urine samples. In all these patients, creatinine and electrolytes were measured in plasma and urine. A new equation was developed using a multiple linear regression model. RESULTS: Twenty-four-hour urine sodium excretion was significantly correlated with age, weight, height, eGFR, plasma osmolarity, urine electrolytes and parameters obtained from spot urine sample, among others. The new equation had a linear correlation with 24-hour natriuresis of 0.91 and the concordance was 0.9. The predictive capacity of the new equation was better than the existing formulas. CONCLUSIONS: We developed a formula to accurately predict daily natriuresis in the Chilean population.
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    Comparison of different methods to estimate glomerular filtration rate in older adults¿Son equivalentes los diferentes métodos para estimar la función renal en los adultos mayores?
    (2021) Vega J.; Huidobro E J.P.; Sepulveda R.A.
    BACKGROUND: Glomerular filtration rate (GFR) estimation in older adults using a creatinine clearance/24-hour (CrCl) or an equation based on serum creatinine, are often considered equivalent by clinicians. AIM: To compare GFR estimated (eGFR) with the available equations and measured CrCl in patients ≥ 70 years. A secondary aim was to know the differences in chronic kidney disease (CKD) classification, when using the different eGFR formulas. PATIENTS AND METHODS: In 144 patients aged 77 ± 5 years (58% men), CrCl was measured and GFR was estimated using MDRD, CKD-EPI, BIS-1 and FAS formulas. The eGFR and the stage of CKD were compared according to the different equations used. RESULTS: GFR estimated by MDRD and CKD-EPI equations was 7.8 and 8.4 mL/min/1.73 m2 lower than 24-hour ClCr, respectively. This difference was even greater using the BIS-1 and FAS equations. Twenty-four-hour CrCl classified 47.2% of the patients in a category of renal function > 60 mL/min/1.73 m2, while MDRD and CKD-EPI equations classified just over a third, and BIS-1 and FAS formulas around 20% of the patients. CONCLUSIONS: The practice of considering equivalent the GFR estimation using the creatinine-based equations with measured creatinine clearance in older adults should be reconsidered, because their results differ markedly.