Sodium bicarbonate treatment had no effect on muscle function or bone mineral density (BMD) in a study of patients with chronic kidney disease (CKD) stages 3 and 4, investigators reported in the American Journal of Kidney Diseases.
As far as they are aware, the study was the first double-blind placebo-controlled trial of sodium bicarbonate treatment in patients with an estimated glomerular filtration rate (eGFR) below 60 mL/min/1.73 m2, a team led by Michal L. Melamed, MD, MHS, of Albert Einstein College of Medicine/Montefiore Medical Center in Bronx, New York, stated. The study also was the first to evaluate the effects of sodium bicarbonate therapy on BMD in patients with CKD, they noted.
Dr Melamed and her colleagues said they conducted the study to address a paucity of placebo-controlled data related to the safety and effects of sodium bicarbonate treatment in patients with CKD. They had hypothesized that sodium bicarbonate therapy would improve muscle function and decrease bone resorption compared with placebo. They randomly assigned 149 patients to receive either sodium bicarbonate 0.4 mEq per kg of ideal body weight per day (74 patients) or identical-appearing placebo (75 patients). The co-primary outcomes were muscle function assessed using sit-to-stand times and BMD measured at the femoral neck using dual-energy x-ray absorptiometry. Patients were seen at baseline and 2, 6, 12, and 24 months.
Baseline characteristics did not differ between the groups. At baseline, patients had a mean serum bicarbonate level of 24 mEq/L and mean eGFR of 36.3 mL/min/1.73 m2. In the intervention arm, mean serum bicarbonate levels during follow-up were 26.4, 25.5, 25.6, and 24.4 mEq/L at 2, 6, 12, and 24 months, respectively, and these levels were significantly higher than in the placebo arm. The sodium bicarbonate recipients displayed no significant difference in sit-to-stand times or BMD compared with the placebo group. The intervention arm experienced a borderline significant decrease in serum potassium levels. Dr Melamed’s team observed no significant differences in eGFR, blood pressure, weight, or serious adverse events.
“A larger randomized clinical trial of sodium bicarbonate therapy, possibly with a larger dose of sodium bicarbonate, is required to evaluate whether treatment with sodium bicarbonate is beneficial for kidney function,” the authors concluded.
Melamed ML, Horwitz EJ, Dobre MA, et al. Effects of sodium bicarbonate in CKD stages 3 and 4: A randomized, placebo-controlled, multicenter clinical trial. Am J Kidney Dis. 2020;75:225-234.