Rajiv Saran1, Robin L Padilla2, Brenda W Gillespie3, Michael Heung4, Scott L Hummel5,6, Vimal Kumar Derebail7, Bertram Pitt5, Nathan W Levin8, Fansan Zhu8, Samer R Abbas8, Li Liu8, Peter Kotanko8,9, Philip Klemmer7. 1. Division of Nephrology, Department of Internal Medicine, rsaran@med.umich.edu. 2. Department of Biostatistics, Kidney Epidemiology and Cost Center. 3. Department of Biostatistics, Consulting for Statistics, Computing and Analytics Research, and. 4. Division of Nephrology, Department of Internal Medicine. 5. Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan. 6. Division Cardiology, Department of Internal Medicine, Ann Arbor Veterans Affairs Health System, Ann Arbor, Michigan. 7. Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. 8. Renal Research Institute, Research Division, New York, New York; and. 9. Division of Nephrology, Department of Internal Medicine, Icahn School of Medicine at Mount Sinai, New York, New York.
Abstract
BACKGROUND AND OBJECTIVES:Patients with chronic kidney disease (CKD) are often volume expanded and hypertensive. Few controlled studies have assessed the effects of a sodium-restricted diet (SRD) in CKD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We conducted a randomized crossover trial to evaluate the effect of SRD (target <2 g sodium per day) versus usual diet on hydration status (by bioelectrical impedance spectroscopy) and blood pressure (BP) between May of 2009 and May of 2013. A total of 58 adults with stage 3-4 CKD were enrolled from two academic sites: University of Michigan (n=37) and University of North Carolina at Chapel Hill (n=21); 60% were men, 43% were diabetic, 93% were hypertensive, and mean age was 61 years. Participants followed SRD or usual diet for 4 weeks, followed by a 2-week washout period and a 4-week crossover phase. During the SRD, dieticians provided counseling every 2 weeks, using motivational interviewing techniques. RESULTS:Whole-body extracellular volume and calf intracellular volume decreased by 1.02 L (95% confidence interval [95% CI], -1.48 to -0.56; P<0.001) and -0.06 L (95% CI, -0.12 to -0.01; P=0.02), respectively, implying decreased fluid content on the SRD compared with usual diet. Significant reductions in urinary sodium (-57.3 mEq/24 h; 95% CI, -81.8 to -32.9), weight (-2.3 kg; 95% CI, -3.2 to -1.5), and 24-hour systolic BP (-10.8 mmHg; 95% CI, -17.0 to -4.6) were also observed (all P<0.01). Albumin-to-creatinine ratio did not change significantly and mean serum creatinine increased slightly (0.1 mg/dl; 95% CI, -0.01 to 0.2; P=0.06). No period or carryover effects were observed. Results were similar when analyzed from phase 1 only before crossover, although P values were modestly larger because of the loss of power. CONCLUSIONS: In this randomized crossover trial, implementation of SRD in patients with CKD stage 3-4 resulted in clinically and statistically significant improvement in BP and hydration status. This simple dietary intervention merits a larger trial in CKD to evaluate effects on major clinical outcomes.
RCT Entities:
BACKGROUND AND OBJECTIVES:Patients with chronic kidney disease (CKD) are often volume expanded and hypertensive. Few controlled studies have assessed the effects of a sodium-restricted diet (SRD) in CKD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We conducted a randomized crossover trial to evaluate the effect of SRD (target <2 g sodium per day) versus usual diet on hydration status (by bioelectrical impedance spectroscopy) and blood pressure (BP) between May of 2009 and May of 2013. A total of 58 adults with stage 3-4 CKD were enrolled from two academic sites: University of Michigan (n=37) and University of North Carolina at Chapel Hill (n=21); 60% were men, 43% were diabetic, 93% were hypertensive, and mean age was 61 years. Participants followed SRD or usual diet for 4 weeks, followed by a 2-week washout period and a 4-week crossover phase. During the SRD, dieticians provided counseling every 2 weeks, using motivational interviewing techniques. RESULTS: Whole-body extracellular volume and calf intracellular volume decreased by 1.02 L (95% confidence interval [95% CI], -1.48 to -0.56; P<0.001) and -0.06 L (95% CI, -0.12 to -0.01; P=0.02), respectively, implying decreased fluid content on the SRD compared with usual diet. Significant reductions in urinary sodium (-57.3 mEq/24 h; 95% CI, -81.8 to -32.9), weight (-2.3 kg; 95% CI, -3.2 to -1.5), and 24-hour systolic BP (-10.8 mmHg; 95% CI, -17.0 to -4.6) were also observed (all P<0.01). Albumin-to-creatinine ratio did not change significantly and mean serum creatinine increased slightly (0.1 mg/dl; 95% CI, -0.01 to 0.2; P=0.06). No period or carryover effects were observed. Results were similar when analyzed from phase 1 only before crossover, although P values were modestly larger because of the loss of power. CONCLUSIONS: In this randomized crossover trial, implementation of SRD in patients with CKD stage 3-4 resulted in clinically and statistically significant improvement in BP and hydration status. This simple dietary intervention merits a larger trial in CKD to evaluate effects on major clinical outcomes.
Authors: Aram V Chobanian; George L Bakris; Henry R Black; William C Cushman; Lee A Green; Joseph L Izzo; Daniel W Jones; Barry J Materson; Suzanne Oparil; Jackson T Wright; Edward J Roccella Journal: Hypertension Date: 2003-12-01 Impact factor: 10.190
Authors: Rikki M Tanner; David A Calhoun; Emmy K Bell; C Barrett Bowling; Orlando M Gutiérrez; Marguerite R Irvin; Daniel T Lackland; Suzanne Oparil; David Warnock; Paul Muntner Journal: Clin J Am Soc Nephrol Date: 2013-07-18 Impact factor: 8.237
Authors: Scott L Hummel; E Mitchell Seymour; Robert D Brook; Samar S Sheth; Erina Ghosh; Simeng Zhu; Alan B Weder; Sándor J Kovács; Theodore J Kolias Journal: Circ Heart Fail Date: 2013-08-28 Impact factor: 8.790
Authors: Nancy R Cook; Jeffrey A Cutler; Eva Obarzanek; Julie E Buring; Kathryn M Rexrode; Shiriki K Kumanyika; Lawrence J Appel; Paul K Whelton Journal: BMJ Date: 2007-04-20
Authors: Katherine J Overwyk; Zerleen S Quader; Joyce Maalouf; Marlana Bates; Jacqui Webster; Mary G George; Robert K Merritt; Mary E Cogswell Journal: Adv Nutr Date: 2020-09-01 Impact factor: 8.701
Authors: Dominique M Bovée; Wesley J Visser; Igor Middel; Anneke De Mik-van Egmond; Rick Greupink; Rosalinde Masereeuw; Frans G M Russel; A H Jan Danser; Robert Zietse; Ewout J Hoorn Journal: J Am Soc Nephrol Date: 2020-01-29 Impact factor: 10.121
Authors: Lingli Li; En Yin Lai; Zaiming Luo; Glenn Solis; Margarida Mendonca; Kathy K Griendling; Anton Wellstein; William J Welch; Christopher S Wilcox Journal: Hypertension Date: 2018-11 Impact factor: 10.190
Authors: Jennifer E Flythe; Tara I Chang; Martin P Gallagher; Elizabeth Lindley; Magdalena Madero; Pantelis A Sarafidis; Mark L Unruh; Angela Yee-Moon Wang; Daniel E Weiner; Michael Cheung; Michel Jadoul; Wolfgang C Winkelmayer; Kevan R Polkinghorne Journal: Kidney Int Date: 2020-03-08 Impact factor: 10.612