Effect of Bicarbonate Supplementation on Renal Function and Nutritional Indices in Predialysis Advanced Chronic Kidney Disease

Abstract

Current practice guidelines recommend alkali therapy in patients with chronic kidney disease (CKD) and metabolic acidosis to prevent complications. This study aims to investigate the effect of oral sodium bicarbonate supplementation on the progression of renal function and nutritional indices in patients with predialysis advanced CKD. Forty patients with predialysis stage 5 CKD(estimated glomerular filtration rate, eGFR <15mL/min per 1.73m2) and 40 patients with stage 4 CKD (eGFR 15 to 30mL/min per 1.73m2) who had a total CO2 less than 22mEq/L were assigned into the bicarbonate treatment group or control group for 12 months. In stage 4 CKD, there were significant differences in the changes of eGFR during the study between the treatment group and the control group (-2.30±4.49 versus -6.58±6.32mL/min/1.73m2, p<0.05). However, in stage 5 CKD, there were no significant differences in the change of eGFR during the study between the two groups (-2.10±2.06 versus -3.23±1.95mL/min/1.73 m2).There were no significant differences in the changes of nutritional indices such as albumin, prealbumin, transferrin, total lymphocyte count (TLC), and Ondodera's prognostic nutritional index (OPNI) during the study between the two groups. In stage 5 CKD, there were significant differences in the changes of TLC and OPNI between the two groups.In conclusion, our results demonstrate that bicarbonate supplementation slows the rate of decline of renal function in stage 4 CKD and improves nutritional indices in stage 5 CKD. Alkali therapy in advanced CKD may have beneficial effect on renal function and malnutrition.

One-Year Conservative Care Using Sodium Bicarbonate Supplementation Is Associated with a Decrease in Electronegative LDL in Chronic Kidney Disease Patients: A Pilot Study

“…Recent studies have addressed the beneficial effect of alkali therapy on the attenuation of progressive renal disease and on nutritional status [19,20,24]. However, a beneficial effect of treatment and prevention of metabolic acidosis on the risk factors of cardiovascular disease has not been consistently addressed.…”

Effects of Treatment of Metabolic Acidosis in CKD

“…Eight of the 14 studies compared oral alkali supplementation (seven studies, sodium bicarbonate; one study, sodium citrate) with a control (no treatment, usual care, or placebo) (7,10,15,(24)(25)(26)(27)(28); five studies compared dietary intervention (ketoanalogue-supplemented very-low-protein diet, verylow-protein diets, low-protein diet, or six-point diet) with control diets (usual diet or low-protein diets) (16,(19)(20)(21)29), whereas one study compared both sodium bicarbonate and dietary intervention (fruits and vegetables) with usual care (Table 1) (14). All trials used a parallel-group design except for the study by Kendrick et al (28), which used a crossover design.…”

Association between serum Na–Cl level and renal function decline in chronic kidney disease: results from the chronic kidney disease Japan cohort (CKD-JAC) study

“…Metabolic acidosis is a well-known complication of chronic kidney disease (CKD), particularly in stages 4 and 5, and reduces the serum level of sodium bicarbonate, which is important for attenuating the rate of kidney disease progression [1–7]. According to the Kidney Disease Improving Global Outcomes (KDIGO) 2012 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease, the serum bicarbonate level in patients with CKD should be 22 mmol/L or higher [8].…”