Metabolic Acidosis in CKD: A Review of Recent Findings

ABSTRACT Metabolic acidosis is fairly common in patients with chronic kidney disease. The prevalence of metabolic acidosis increases with worsening kidney function, and is observed in approximately 40% of those with stage 4 chronic kidney disease. For the past two decades, clinical practice guidelines have suggested treatment of metabolic acidosis to counterbalance adverse effects of metabolic acidosis on bone and muscle. Studies in animal models of chronic kidney disease also demonstrated that metabolic acidosis causes kidney fibrosis. Over the past decade, results from observational studies identified associations between metabolic acidosis and adverse kidney outcomes, and results from interventional studies support the hypothesis that treating metabolic acidosis with sodium bicarbonate preserves kidney function. However, convincing data from large-scale double-blinded, placebo-controlled, randomized trials has been lacking. This review discusses findings from recent interventional trials of alkali therapy in CKD and new findings linking metabolic acidosis with cardiovascular disease in adults and CKD progression in children. Finally, a novel agent that treats metabolic acidosis in patients with chronic kidney disease by binding hydrochloric acid in the gastrointestinal tract is discussed.