Azizudin Ashlee M, Silver Samuel A, Garg Amit X, Friedman Zoe K, Cowan Andrea C, Clase Catherine M, Molnar Amber O
Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada.
Division of Nephrology, Department of Medicine, Queen's University, Kingston, ON, Canada.
Can J Kidney Health Dis. 2025 Jul 31;12:20543581251356182. doi: 10.1177/20543581251356182. eCollection 2025.
Metabolic acidosis is a common complication of kidney failure that is treated with bicarbonate supplementation. The addition of bicarbonate to the dialysis solution and oral bicarbonate supplementation are used to treat metabolic acidosis in patients receiving dialysis, but the treatment approach that is best for patient health remains unknown.
The purpose of this study was to determine whether the concentration of dialysate bicarbonate or the use of oral bicarbonate supplementation alters the risk of mortality, hospitalizations, cardiovascular and nutritional outcomes, and laboratory measurements in patients treated with maintenance dialysis.
Systematic review and meta-analysis.
Any country of origin.
Adult patients (≥18 years) receiving maintenance dialysis.
Extracted data included demographic characteristics and outcomes such as mortality, hospitalizations, cardiovascular events, surrogate markers of nutrition, and pre-dialysis and post-dialysis levels of serum bicarbonate, pH, calcium, potassium, and parathyroid hormone.
We searched MEDLINE, Embase, CENTRAL, and Google Scholar through October 7, 2024 for studies examining dialysate bicarbonate concentration and/or oral bicarbonate supplementation in adults undergoing maintenance dialysis. Meta-analysis was performed for pre-dialysis serum bicarbonate and for pre-dialysis and post-dialysis calcium and potassium.
We identified 37 studies (n = 24,782 patients) with patients treated with hemodialysis (13 randomized trials, 10 non-randomized interventional studies, 14 observational studies) and 4 studies (n = 347 patients) with patients receiving peritoneal dialysis (3 randomized trials, 1 non-randomized interventional study). No randomized trials reported mortality or hospitalizations in hemodialysis patients. Studies reporting cardiovascular outcomes (n = 20) were small with inconsistent results. Most studies reporting nutritional outcomes (n = 21) reported no significant differences with dialysate bicarbonate concentration or oral bicarbonate supplementation but were small in sample size (largest study n = 200). Meta-analysis of parallel-group randomized trials comparing dialysate bicarbonate >35 mmol/L with ≤35 mmol/L found a mean difference of 3.5 mmol/L (95% confidence interval [CI] -0.6 to 7.7) in pre-dialysis serum bicarbonate.
Non-English and gray literature were excluded. Most studies were small or observational in nature, and heterogeneity further limited the ability to perform meta-analysis of outcomes such as mortality, hospitalizations, and cardiovascular outcomes.
The evidence for the effect of higher vs lower dialysate bicarbonate concentration and oral bicarbonate supplementation on clinical outcomes in dialysis patients is very uncertain. There is a need for large, high-quality randomized controlled trials in this area.
代谢性酸中毒是肾衰竭的常见并发症，通常采用补充碳酸氢盐进行治疗。在透析液中添加碳酸氢盐以及口服补充碳酸氢盐被用于治疗接受透析患者的代谢性酸中毒，但对患者健康最有利的治疗方法仍不明确。
本研究的目的是确定透析液中碳酸氢盐的浓度或口服补充碳酸氢盐是否会改变维持性透析患者的死亡风险、住院率、心血管和营养结局以及实验室检测指标。
系统评价和荟萃分析。
任何国家。
接受维持性透析的成年患者（≥18岁）。
提取的数据包括人口统计学特征和结局，如死亡率、住院率、心血管事件、营养替代指标以及透析前和透析后血清碳酸氢盐、pH值、钙、钾和甲状旁腺激素水平。
我们检索了截至2024年10月7日的MEDLINE、Embase、CENTRAL和谷歌学术，以查找关于接受维持性透析的成年人透析液中碳酸氢盐浓度和/或口服补充碳酸氢盐的研究。对透析前血清碳酸氢盐以及透析前和透析后钙和钾进行荟萃分析。
我们纳入了37项研究（n = 24782例患者），其中患者接受血液透析（13项随机试验、10项非随机干预研究、14项观察性研究），以及4项研究（n = 347例患者），其中患者接受腹膜透析（3项随机试验、1项非随机干预研究）。没有随机试验报告血液透析患者的死亡率或住院率。报告心血管结局的研究（n = 20）规模较小且结果不一致。大多数报告营养结局的研究（n = 21）报告称，透析液中碳酸氢盐浓度或口服补充碳酸氢盐之间没有显著差异，但样本量较小（最大的研究n = 200）。对比较透析液碳酸氢盐>35 mmol/L与≤35 mmol/L的平行组随机试验进行荟萃分析发现，透析前血清碳酸氢盐的平均差异为3.5 mmol/L（95%置信区间[CI] -0.6至7.7）。
排除了非英文文献和灰色文献。大多数研究规模较小或本质上是观察性的，异质性进一步限制了对死亡率、住院率和心血管结局等结局进行荟萃分析的能力。
透析液中碳酸氢盐浓度较高与较低以及口服补充碳酸氢盐对透析患者临床结局影响的证据非常不确定。该领域需要大型、高质量的随机对照试验。
