Treatment of Chronic Kidney Disease-Related Metabolic Acidosis With Fruits and Vegetables Compared to NaHCO₃ Yields More and Better Overall Health Outcomes and at Comparable Five-Year Cost

Objectives: Current guidelines recommend treatment of metabolic acidosis in chronic kidney disease (CKD) with Na⁺-based alkali but base-producing fruits and vegetables (F + V) might yield more and better health outcomes, making the intervention cost-effective.

Design and methods: In this post hoc analysis of a clinical trial we randomized 108 macroalbuminuric, nondiabetic CKD stage 3 participants with metabolic acidosis to receive F + V (n = 36) calculated to reduce dietary acid by half, oral NaHCO₃ (HCO₃^-, n = 36) 0.3 mEq/kg body weight/day, or Usual Care (UC, n = 36) assessed annually for 5 years. We calculated a mean overall health score for the groups as follows: 1 for improved, 0 for no change, and -1 for worsened at 5 years for plasma total CO₂, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, change in medication dose (reduction = 1, increased = -1, no change = 0), and 1 for met goal and 0 for not meeting goal for estimated glomerular filtration rate (>30 mL/min/1.73 m²) and systolic blood pressure (<130 mm Hg). We also assessed the number of participants with cardiovascular disease events (myocardial infarctions + strokes) and group medication and hospitalization costs.

Results: Net plasma total CO₂ increase at 5 years was no different between HCO₃^- and F + V. Average health scores at 5 years differed among groups (P < .01) with F + V (7.4 [mean] ± 1.6 [standard deviation]) being descriptively larger than HCO₃^- and UC (2.9 ± 1.6 and 1.2 ± 1.6, respectively). The number of participants suffering cardiovascular disease events differed among groups (P = .009) with none (0) in F + V, 6 in UC, and 2 in HCO₃^-. Total 5-year household cost per beneficial health outcome differed among groups (P = .005) with UC being highest and that for HCO₃^- and F + V being comparable.

Conclusions: Metabolic acidosis improved comparably with F + V or standard oral NaHCO₃, but F + V yielded ancillary beneficial health outcomes, fewer participants with adverse cardiovascular events, and per-household cost that was comparable to NaHCO₃.