Uribarri Jaime, Guedes Murilo, Diaz Bessone Maria Ines, Chan Lili, de la Torre Andres, Mermelstein Ariella, Garcia-Garcia Guillermo, Raimann Jochen, Moraes Thyago, Peters Vincent, Konings Constantijn, Farrell Douglas, Sharma Shuchita, Guinsburg Adrian, Kotanko Peter
Renal Division, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York.
Department of Medicine, School of Medicine, Pontificia Universidade Catolica do Parana, Curitiba, Brazil.
Kidney360. 2025 Jan 1;6(1):105-111. doi: 10.34067/KID.0000000618. Epub 2024 Oct 11.
This is a retrospective observational multinational peritoneal dialysis study to test whether creatinine clearance could be a better marker of serum phosphorus than urea Kt/V. Creatinine clearance was not more accurate predicting serum phosphorus than urea Kt/V, but its inclusion in multivariable models added more clarity. In conclusion, using both biomarkers, instead of just one, may better assist in the optimization of serum phosphorus levels.
Hyperphosphatemia is associated with poor outcome and is still very common in peritoneal dialysis (PD) patients. Because peritoneal phosphorus clearance is closer to peritoneal creatinine clearance (CrCl) than urea clearance, we hypothesized that weekly CrCl could be a better marker of serum phosphorus in PD.
In a retrospective observational study, data from adult PD patients were collected across five institutions in North and South America: Fresenius Medical Care Latin America, Renal Research Institute, Mount Sinai Hospital, Hospital Civil de Guadalajara, and the Brazil PD cohort. All centers analyzed routinely available laboratory data, with exclusions for missing data on serum phosphorus, CrCl, or urea Kt/V. A unified statistical protocol was used across centers. Linear mixed-effect models examined associations between longitudinal serum phosphorus levels, CrCl, and Kt/V. Adjustments were made for age, sex, and baseline phosphorus binder usage. Mixed-effects meta-analysis determined the pooled effect size of CrCl and Kt/V on serum phosphorus trajectories, adjusted for confounders.
There were 16,796 incident PD patients analyzed. Age, body mass index, sex, PD modality, Kt/V, and CrCl, as well as serum phosphorus, varied significantly across the different cohorts, but >70% had residual renal function. For most cohorts, both CrCl total and urea Kt/V associated negatively with serum phosphorus levels, and log-likelihood ratio tests demonstrate that models including CrCltotal have more predictive information than those including only urea Kt/V for the largest cohorts. Models including CrCltotal increase information predicting longitudinal serum phosphorus levels irrespective of baseline urea Kt/V, age, use of phosphorus binder, and sex.
CrCl was not more accurate in predicting serum phosphorus than urea Kt/V, but its inclusion in multivariable models predicting serum phosphorus added accuracy. In conclusion, both CrCl and Kt/V are associated with phosphorus levels, and using both biomarkers, instead of just one, may better assist in the optimization of serum phosphorus levels.
这是一项回顾性观察性跨国腹膜透析研究，旨在测试肌酐清除率是否可能是比尿素Kt/V更好的血清磷标志物。肌酐清除率在预测血清磷方面并不比尿素Kt/V更准确，但将其纳入多变量模型能增加更多清晰度。总之，使用这两种生物标志物而非仅一种，可能更有助于优化血清磷水平。
高磷血症与不良预后相关，在腹膜透析（PD）患者中仍然非常常见。由于腹膜磷清除率比尿素清除率更接近腹膜肌酐清除率（CrCl），我们假设每周CrCl可能是PD患者血清磷的更好标志物。
在一项回顾性观察研究中，收集了来自北美和南美五个机构的成年PD患者数据：费森尤斯医疗护理拉丁美洲公司、肾脏研究所、西奈山医院、瓜达拉哈拉市民医院和巴西PD队列。所有中心分析常规可得的实验室数据，排除血清磷、CrCl或尿素Kt/V数据缺失的情况。各中心使用统一的统计方案。线性混合效应模型研究纵向血清磷水平、CrCl和Kt/V之间的关联。对年龄、性别和基线磷结合剂使用情况进行了调整。混合效应荟萃分析确定了CrCl和Kt/V对血清磷轨迹的合并效应大小，并对混杂因素进行了调整。
共分析了16796例新发PD患者。年龄、体重指数、性别、PD方式、Kt/V和CrCl以及血清磷在不同队列中差异显著，但超过70%的患者有残余肾功能。对于大多数队列，总CrCl和尿素Kt/V均与血清磷水平呈负相关，对数似然比检验表明，对于最大的队列，包含总CrCl的模型比仅包含尿素Kt/V的模型具有更多预测信息。无论基线尿素Kt/V、年龄、磷结合剂使用情况和性别如何，包含总CrCl的模型都能增加预测纵向血清磷水平的信息。
CrCl在预测血清磷方面并不比尿素Kt/V更准确，但将其纳入预测血清磷的多变量模型可提高准确性。总之，CrCl和Kt/V均与磷水平相关，使用这两种生物标志物而非仅一种，可能更有助于优化血清磷水平。
