Abstract：
BACKGROUND: Thrice weekly hemodialysis (HD) is currently the norm in high income countries but there is mounting interest in twice weekly HD in certain settings. We performed this systematic review to summarize the available evidence comparing twice to thrice weekly HD.
METHODS: A systematic literature search was performed in Ovid MEDLINE, Ovid Embase, and the Cochrane Central Register of Controlled Trials to identify cohort and randomized controlled trials evaluating outcomes of twice versus thrice weekly HD. The bibliographies of identified studies were hand searched to find any additional studies. Risk of bias was assessed using the Newcastle-Ottawa scale for observational studies.
RESULTS: No randomized controlled trials and 21 cohort studies were identified. Overall study quality was modest with high risk of selection bias and inadequate controlling for confounders. The most commonly evaluated outcome measures were survival and residual kidney function. No studies assessed quality of life. Study results were variable and there was no clear signal for overwhelming risk or benefit of twice versus thrice weekly HD with the exception of residual kidney function which consistently showed slower decline in the twice weekly group.
CONCLUSIONS: There is a paucity of high quality data comparing the risks and benefits of twice vs thrice weekly HD. Randomized controlled trial evidence is required to inform clinicians and HD prescription guidelines.
METHODS: A systematic literature search was performed in Ovid MEDLINE, Ovid Embase, and the Cochrane Central Register of Controlled Trials to identify cohort and randomized controlled trials evaluating outcomes of twice versus thrice weekly HD. The bibliographies of identified studies were hand searched to find any additional studies. Risk of bias was assessed using the Newcastle-Ottawa scale for observational studies.
RESULTS: No randomized controlled trials and 21 cohort studies were identified. Overall study quality was modest with high risk of selection bias and inadequate controlling for confounders. The most commonly evaluated outcome measures were survival and residual kidney function. No studies assessed quality of life. Study results were variable and there was no clear signal for overwhelming risk or benefit of twice versus thrice weekly HD with the exception of residual kidney function which consistently showed slower decline in the twice weekly group.
CONCLUSIONS: There is a paucity of high quality data comparing the risks and benefits of twice vs thrice weekly HD. Randomized controlled trial evidence is required to inform clinicians and HD prescription guidelines.
摘要：
背景：目前在高收入国家，每周进行三次血液透析（HD）是常态，但在某些情况下，每周进行两次血液透析的兴趣越来越大。我们进行了这项系统评价，以总结每周两次至三次的HD比较的可用证据。
方法：在OvidMEDLINE进行了系统的文献检索，OvidEmbase,和Cochrane中央对照试验登记册，以确定队列和随机对照试验，评估每周两次和三次HD的结局。手工搜索已确定研究的参考书目，以找到任何其他研究。使用纽卡斯尔-渥太华量表进行观察性研究，评估偏倚风险。
结果：没有确定随机对照试验和21项队列研究。总体研究质量不高，选择偏倚风险高，对混杂因素控制不足。最常评估的结果指标是生存率和残余肾功能。没有研究评估生活质量。研究结果是可变的，并且没有明确的信号表明每周两次与每周三次HD的压倒性风险或益处，但残余肾功能除外，其在每周两次的组中始终显示出较慢的下降。
结论：缺乏比较每周两次和三次HD的风险和收益的高质量数据。需要随机对照试验证据来告知临床医生和HD处方指南。
方法：在OvidMEDLINE进行了系统的文献检索，OvidEmbase,和Cochrane中央对照试验登记册，以确定队列和随机对照试验，评估每周两次和三次HD的结局。手工搜索已确定研究的参考书目，以找到任何其他研究。使用纽卡斯尔-渥太华量表进行观察性研究，评估偏倚风险。
结果：没有确定随机对照试验和21项队列研究。总体研究质量不高，选择偏倚风险高，对混杂因素控制不足。最常评估的结果指标是生存率和残余肾功能。没有研究评估生活质量。研究结果是可变的，并且没有明确的信号表明每周两次与每周三次HD的压倒性风险或益处，但残余肾功能除外，其在每周两次的组中始终显示出较慢的下降。
结论：缺乏比较每周两次和三次HD的风险和收益的高质量数据。需要随机对照试验证据来告知临床医生和HD处方指南。
