Kidney Week

Abstract: SA-OR037

The Effects of Sodium Bicarbonate in CKD Stages 3 and 4: A Randomized, Placebo-Controlled, Multi-Center Clinical Trial

Session Information

• Fluids and Electrolytes: Clinical, Translational, and Acid-Base
  October 27, 2018 | Location: 23A, San Diego Convention Center
  Abstract Time: 05:42 PM - 05:54 PM

Category: Fluid and Electrolytes

• 902 Fluid and Electrolytes: Clinical

Authors

• Melamed, Michal L., Albert Einstein College of Medicine, Bronx, New York, United States

Michal L. Melamed, MD

• Horwitz, Edward J., Case Western Reserve University, Cleveland, Ohio, United States

Edward J. Horwitz,

• Dobre, Mirela A., Case Western Reserve University, Cleveland, Ohio, United States

Mirela A. Dobre,

• Abramowitz, Matthew K., Albert Einstein College of Medicine, Bronx, New York, United States

Matthew K. Abramowitz,

• Lo, Yungtai, Albert Einstein College of Medicine, Bronx, New York, United States

Yungtai Lo,

• Hostetter, Thomas H., Case Western Reserve University, Cleveland, Ohio, United States

Thomas H. Hostetter,

Background

The chronic metabolic acidosis associated with kidney disease may contribute to muscle dysfunction, bone disease and progression of kidney disease.

Methods

We enrolled 149 patients with CKD stages 3 and 4 and randomized them to either placebo or sodium bicarbonate (NaBicarb) (0.4 mEq/kg ideal body weight/day) between 7/2011 and 4/2016 at 3 clinical sites across the US. Participants were seen at baseline, 2, 6, 12 and 24 months. The dual primary outcomes were muscle function assessed by sit-to-stand-to-sit test and bone mineral density. At each visit, blood pressure (BP), weight, a 5-repetition sit-to-stand-to-sit test, and laboratory studies were conducted. Bone mineral density scans were performed at baseline, 12 and 24 months.

Results

Of the 149 participants, 74 were on NaBicarb, 75 were on placebo. Mean age was 61.0 years (standard deviation(SD) 12.6), 54% were women, 58% were non-Hispanic black, 13% were Hispanic and 27% were non-Hispanic white, 62% had diabetes mellitus and 93% had hypertension at baseline. Baseline serum bicarbonate level was 23.5 (SD 1.7) mEq/L, baseline eGFR was 36.3 (SD 11.2) ml/min/1.73m² and baseline systolic BP was 137 (SD 17) mmHg. There were no differences in baseline characteristics by treatment group. 104 participants completed the 24 months study. At 2, 6, 12 and 24 months, the mean serum bicarbonate levels in the NaBicarb arm were 26.4 mEq/L (SD 2.2), 25.5 mEq/L (SD 2.3), 25.6 mEq/L (SD 2.6) and 24.4 mEq/L (SD 2.8). These were significantly higher than in the placebo group (p<0.001). NaBicarb caused a significant decrease in serum potassium levels by approximately 0.1 mEq/L (p= 0.047). There were 14 patients in the NaBicarb group who had a potassium level >5.0 mEq/L over the course of the study compared to 30 patients in the placebo group (p=0.005). There were no significant differences in sit-to-stand-to-sit time, bone mineral density, BP or weight between the randomized groups.

Conclusion

NaBicarb therapy in patients with CKD stages 3 and 4 significantly increases serum bicarbonate and decreases serum potassium levels. There were no differences in muscle function or bone mineral density between the randomized groups. Larger trials are required to evaluate effects on kidney function.

Funding

• NIDDK Support