Deved Vinay, Poyah Penelope, James Matthew T, Tonelli Marcello, Manns Braden J, Walsh Michael, Hemmelgarn Brenda R
Department of Medicine, University of Calgary, Calgary, Alberta, Canada.
Am J Kidney Dis. 2009 Dec;54(6):1089-97. doi: 10.1053/j.ajkd.2009.06.040. Epub 2009 Sep 23.
Ascorbic acid is believed to improve anemia in patients with end-stage renal disease, but its overall effectiveness is unclear.
Systematic review and meta-analysis.
SETTING & POPULATION: Adult hemodialysis patients.
Randomized clinical trials of ascorbic acid use in addition to standard anemia management.
Ascorbic acid.
Weighted mean difference (WMD) for change in hemoglobin level, recombinant human erythropoietin (rHuEPO) dose, transferrin saturation and ferritin level and adverse events.
Of 157 potentially relevant studies, 6 studies (n = 326 patients) met the inclusion criteria. Combining the 3 randomized clinical trials involving patients with baseline hemoglobin levels <11 g/dL, change in hemoglobin level was greater for ascorbic acid use compared with standard care (WMD, 0.9 g/dL; 95% CI, 0.5-1.2 g/dL). Compared with standard care, ascorbic acid use also was associated with a statistically significant decrease in rHuEPO dose (WMD, -17.1 U/kg/wk; 95% CI, -26.0 to -8.2 U/kg/wk) and improvement in transferrin saturation (WMD, 7.9%; 95% CI, 5.2-10.5%), with no change in ferritin concentration. Adverse events had questionable relevance to ascorbic acid use; no study reported oxalate levels or occurrence of oxalosis.
Small number of studies, heterogeneity between study populations, and study durations were short. Adverse events were poorly reported.
Although the studies are limited by small numbers of subjects, short durations of follow-up, and variable quality, these results suggest that compared with standard care, ascorbic acid use may result in an increase in hemoglobin concentration and transferrin saturation and decrease in rHuEPO requirements. Longer term studies are required to confirm these results, provide information about adverse events, and determine whether these changes translate into improved patient outcomes and cost-effectiveness.
人们认为抗坏血酸可改善终末期肾病患者的贫血状况，但其总体疗效尚不清楚。
系统评价和荟萃分析。
成年血液透析患者。
除标准贫血管理外使用抗坏血酸的随机临床试验。
抗坏血酸。
血红蛋白水平变化、重组人促红细胞生成素（rHuEPO）剂量、转铁蛋白饱和度和铁蛋白水平的加权平均差（WMD）以及不良事件。
在157项可能相关的研究中，6项研究（n = 326例患者）符合纳入标准。综合3项涉及基线血红蛋白水平<11 g/dL患者的随机临床试验，与标准治疗相比，使用抗坏血酸后血红蛋白水平变化更大（WMD，0.9 g/dL；95%CI，0.5 - 1.2 g/dL）。与标准治疗相比，使用抗坏血酸还与rHuEPO剂量有统计学意义的降低（WMD，-17.1 U/kg/周；95%CI，-26.0至-8.2 U/kg/周）以及转铁蛋白饱和度的改善（WMD，7.9%；95%CI，5.2 - 10.5%）相关，铁蛋白浓度无变化。不良事件与使用抗坏血酸的相关性存疑；没有研究报告草酸盐水平或草酸盐中毒的发生情况。
研究数量少、研究人群存在异质性且研究持续时间短。不良事件报告不充分。
尽管这些研究受到受试者数量少、随访时间短和质量参差不齐的限制，但这些结果表明，与标准治疗相比，使用抗坏血酸可能会导致血红蛋白浓度和转铁蛋白饱和度升高以及rHuEPO需求降低。需要进行长期研究以证实这些结果，提供有关不良事件的信息，并确定这些变化是否能转化为改善患者预后和成本效益。
