Greene Tom, Daugirdas John T, Depner Thomas A, Gotch Frank, Kuhlman Martin
National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD, USA.
Am J Kidney Dis. 2009 May;53(5):835-44. doi: 10.1053/j.ajkd.2008.12.039. Epub 2009 Apr 1.
The Frequent Hemodialysis Network (FHN) is conducting 2 randomized clinical trials, a daytime in-center trial ("daily") comparing 6 versus 3 treatments/wk, and a home nocturnal trial comparing 6 nocturnal treatments versus 3 conventional treatments/wk. The goal of this study was to project separation between the treatment and control arms of these studies for measures of dialysis dose by using simulations based on 2-compartment variable-volume models.
SETTING & PARTICIPANTS: Data from the most recent hemodialysis treatment in 100 patients dialyzed 3 times/wk at facilities of the Renal Research Institute in New York and from 2 data sets (n = 154 and 115 patients) from the Hemodialysis (HEMO) trial.
Observational study.
Dialysis prescriptions for the treatment and control arms in the FHN trials. DIALYSIS REGIMEN OUTCOMES: Treatment time, ultrafiltration rate, standard Kt/V/wk for urea (stdKt/V(urea)), and continuous clearance estimates based on ratios of urea, creatinine, and normalized beta(2)-microglobulin generation rates (denoted by Gn) to time-averaged concentrations (TACs) of these solutes during 1 treatment week.
The expected differences between median values in the experimental and control groups were weekly treatment time: daily trial, 29%; nocturnal trial, 234%; ultrafiltration rate: daily, -20%; nocturnal, -69%; stdKt/V(urea): daily, 52%; nocturnal, 133%; Gn(urea)/TAC(urea): daily, 34%; nocturnal, 130%; Gn(cr)/TAC(cr): daily, 31%; nocturnal, 135%; and Gn(beta2)/TAC(beta2): daily, 8%; nocturnal, 67%.
Use of simulated data and assumption of equivalent volumes and ultrafiltration rates between treatment arms.
The nocturnal 6-times-weekly regimen produces substantially greater separation between the treatment and control arms than the daytime 6-times-weekly regimen for a wide range of treatment parameters. However, the 6-times-weekly interventions in both FHN trials will produce substantially greater separation than in the HEMO trial, where separations in median weekly treatment time and stdKt/V(urea) between the 3-times-weekly high- and standard-dose groups were 18% and 17%, respectively. The FHN trials will test whether substantial increases in solute clearance and other effects of frequent hemodialysis materially influence selected intermediate outcome measures.
频繁血液透析网络（FHN）正在进行两项随机临床试验，一项日间中心试验（“每日”）比较每周6次与3次治疗，以及一项家庭夜间试验比较每周6次夜间治疗与3次传统治疗。本研究的目的是通过基于两室可变容积模型的模拟，预测这些研究中治疗组和对照组在透析剂量测量方面的分离情况。
来自纽约肾脏研究所每周透析3次的100名患者最近一次血液透析治疗的数据，以及来自血液透析（HEMO）试验的2个数据集（n = 154和115名患者）。
观察性研究。
FHN试验中治疗组和对照组的透析处方。
治疗时间、超滤率、尿素的标准Kt/V/周（stdKt/V(尿素)），以及基于尿素、肌酐和标准化β2-微球蛋白生成率（由Gn表示）与这些溶质在1个治疗周内的时间平均浓度（TAC）之比的持续清除率估计值。
实验组和对照组中位数之间的预期差异为每周治疗时间：日间试验，29%；夜间试验，234%；超滤率：日间，-20%；夜间，-69%；stdKt/V(尿素)：日间，52%；夜间，133%；Gn(尿素)/TAC(尿素)：日间，34%；夜间，130%；Gn(肌酐)/TAC(肌酐)：日间，31%；夜间，135%；以及Gn(β2)/TAC(β2)：日间，8%；夜间，67%。
使用模拟数据以及假设治疗组之间的容积和超滤率相等。
对于广泛的治疗参数，每周6次夜间治疗方案在治疗组和对照组之间产生的分离比每周6次日间治疗方案大得多。然而，FHN试验中的每周6次干预将比HEMO试验产生更大的分离，在HEMO试验中，每周3次高剂量组和标准剂量组之间的每周治疗时间中位数和stdKt/V(尿素)的分离分别为18%和17%。FHN试验将测试溶质清除率的大幅提高以及频繁血液透析的其他影响是否会实质性地影响选定的中间结局指标。
