Manish M Sood1, Mahwash Saeed2, Vincent Lim2, Francisco Cordova2, Paul Komenda3, Amrit Malik2, Claudio Rigatto3, Leigh Anne Shafer4, Navdeep Tangri3, Paramjit S Tappia5, Shelley Zieroth2. 1. Ottawa Institute for Clinical Evaluative Sciences, Ottawa Hospital Research Institute, Department of Medicine, University of Ottawa, Ontario, Canada. Electronic address: msood99@gmail.com. 2. Department of Medicine, University of Manitoba, St Boniface Hospital, Winnipeg, Manitoba, Canada. 3. Department of Medicine, University of Manitoba, Seven Oaks Hospital, Winnipeg, Manitoba, Canada. 4. Health Sciences Centre, Department of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada. 5. Asper Clinical Research Institute, St Boniface Hospital Research, Winnipeg, Manitoba, Canada.
Abstract
BACKGROUND: Changes in kidney function in heart failure patients convey important prognostic information. We investigated the association of the urea-to-creatinine (BUN/Cr) ratio, the fractional excretion of urea (FeUr), and the fractional excretion of sodium (FeNa) and subsequent declines in kidney function in ambulatory heart failure patients. METHODS AND RESULTS: We prospectively enrolled adult patients with ejection fraction <40% at a multidisciplinary heart failure clinic and measured serial measurements of laboratory values from September 2008 to July 2011. The study outcome was changes in the estimated glomerular filtration rate (eGFR). In 138 patients contributing 10,350 patient-hours of follow-up, we found that participants with a decline of >25% in eGFR had higher mean BUN/Cr ratio (0.110 ± 0.043 vs 0.086 ± 0.026; P = .02) and no difference in the FeNa (1.81 vs 1.43; P = .2) or FeUr (32.3 vs 37.2; P = .9) compared with those with no change. There was an association of BUN/Cr ratio with the rate of change of eGFR (coefficient -25.67, 95% confidence interval [CI] -10.99 to -40.35; P < .0001). The BUN/Cr ratio was an independent predictor of eGFR drop >25% (odds ratio 1.19, 95% CI 1.07-1.32) and improved model discrimination (c-statistic increased from 0.624 to 0.693) and reclassification (net reclassification index 11.38% [P < .0001], integrated discrimination improvement 5.24% [P = .02]). CONCLUSIONS: The BUN/Cr ratio is associated with worsening kidney function and adds incremental risk prediction information relative to traditional predictive measures in outpatients with heart failure at risk for worsening kidney disease.
BACKGROUND: Changes in kidney function in heart failurepatients convey important prognostic information. We investigated the association of the urea-to-creatinine (BUN/Cr) ratio, the fractional excretion of urea (FeUr), and the fractional excretion of sodium (FeNa) and subsequent declines in kidney function in ambulatory heart failurepatients. METHODS AND RESULTS: We prospectively enrolled adult patients with ejection fraction <40% at a multidisciplinary heart failure clinic and measured serial measurements of laboratory values from September 2008 to July 2011. The study outcome was changes in the estimated glomerular filtration rate (eGFR). In 138 patients contributing 10,350 patient-hours of follow-up, we found that participants with a decline of >25% in eGFR had higher mean BUN/Cr ratio (0.110 ± 0.043 vs 0.086 ± 0.026; P = .02) and no difference in the FeNa (1.81 vs 1.43; P = .2) or FeUr (32.3 vs 37.2; P = .9) compared with those with no change. There was an association of BUN/Cr ratio with the rate of change of eGFR (coefficient -25.67, 95% confidence interval [CI] -10.99 to -40.35; P < .0001). The BUN/Cr ratio was an independent predictor of eGFR drop >25% (odds ratio 1.19, 95% CI 1.07-1.32) and improved model discrimination (c-statistic increased from 0.624 to 0.693) and reclassification (net reclassification index 11.38% [P < .0001], integrated discrimination improvement 5.24% [P = .02]). CONCLUSIONS: The BUN/Cr ratio is associated with worsening kidney function and adds incremental risk prediction information relative to traditional predictive measures in outpatients with heart failure at risk for worsening kidney disease.
Authors: Simge Acar; Sueda Sanli; Cinar Oztosun; Baris Afsar; Alan A Sag; Masanari Kuwabara; Adrian Covic; Alberto Ortiz; Mehmet Kanbay Journal: Int Urol Nephrol Date: 2021-01-03 Impact factor: 2.370