Boyle Suzanne M, Li Yimei, Wilson F Perry, Glickman Joel D, Feldman Harold I
Drexel University College of Medicine, Philadelphia, PA, USA
University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA.
Perit Dial Int. 2017;37(1):85-93. doi: 10.3747/pdi.2015.00227. Epub 2016 Sep 28.
♦ BACKGROUND: Total body water (V) is an imprecise metric for normalization of dialytic urea clearance (Kt). This poses a risk of early mortality/technique failure (TF). We examined differences in the distribution of peritoneal Kt/V when V was calculated with actual weight (AW), ideal weight (IW), and adjusted weight (ADW). We also examined the associations of these Kt/V measurements, Kt/body surface area (BSA), and non-normalized Kt with mortality and TF. ♦ METHODS: This is a retrospective cohort study of 534 incident peritoneal dialysis (PD) patients from the Dialysis Morbidity and Mortality Study Wave 2 linked with United States Renal Data System through 2010. Using Cox-proportional hazard models, we examined the relationship of several normalization strategies for peritoneal urea clearance, including Kt/V, Kt/V, Kt/V, Kt/BSA, and non-normalized Kt, with the outcomes of mortality and TF. Harrell's c-statistics were used to assess the relative predictive ability of clearance metrics for mortality and TF. The distributions of Kt/V, KT/V, and KT/V were compared within and between body mass index (BMI) strata. ♦ RESULTS: Median patient age: 59 (54% male; 72% white; 91% continuous ambulatory PD [CAPD]). Median 24-hour urine volume: 700 mL; median estimated glomerular filtration rate (eGFR) at initiation: 7.15 mL/min/1.73 m. Technique failure and transplant-censored mortality at 5 years: 37%. Death and transplant-censored TF at 5 years: 60%. There were no significant differences in initial eGFR and 24-hour urine volume across BMI strata. There were statistically significant differences in each Kt/V calculation within the underweight, overweight, and obese strata. After adjustment, there were no significant differences in the hazard ratios (HRs) for TF/mortality for each clearance calculation. Harrell's c-statistics for mortality for each clearance calculation were 0.78, and for TF, 0.60 - 0.61. ♦ CONCLUSIONS: Peritoneal urea clearances are sensitive to subtle changes in the estimation of V. However, there were no detectable significant associations of Kt/V, Kt/V, Kt/V, Kt/BSA, or Kt with TF or mortality.
♦ 背景：总体水（V）作为透析尿素清除率（Kt）标准化的指标并不精确。这带来了早期死亡/技术失败（TF）的风险。我们研究了用实际体重（AW）、理想体重（IW）和校正体重（ADW）计算V时，腹膜Kt/V分布的差异。我们还研究了这些Kt/V测量值、Kt/体表面积（BSA）和未标准化的Kt与死亡率和TF之间的关联。♦ 方法：这是一项对534例新发腹膜透析（PD）患者的回顾性队列研究，这些患者来自透析发病率和死亡率研究第2波，并通过2010年与美国肾脏数据系统相链接。我们使用Cox比例风险模型，研究了腹膜尿素清除率的几种标准化策略，包括Kt/V、Kt/V、Kt/V、Kt/BSA和未标准化的Kt，与死亡率和TF结局之间的关系。使用Harrell c统计量来评估清除率指标对死亡率和TF的相对预测能力。在体重指数（BMI）分层内和分层之间比较了Kt/V、KT/V和KT/V的分布。♦ 结果：患者年龄中位数：59岁（54%为男性；72%为白人；91%为持续性非卧床腹膜透析[CAPD]）。24小时尿量中位数：700 mL；开始时估计肾小球滤过率（eGFR）中位数：7.15 mL/min/1.73 m²。5年时技术失败和移植审查死亡率：37%。5年时死亡和移植审查TF：60%。各BMI分层的初始eGFR和24小时尿量无显著差异。在体重过轻、超重和肥胖分层内，每种Kt/V计算方法均存在统计学显著差异。调整后，每种清除率计算方法的TF/死亡率风险比（HRs）无显著差异。每种清除率计算方法的死亡率Harrell c统计量为0.78，TF为0.60 - 0.61。♦ 结论：腹膜尿素清除率对V估计值的细微变化敏感。然而，未检测到Kt/V、Kt/V、Kt/V、Kt/BSA或Kt与TF或死亡率之间存在显著关联。
