Department of Nephrology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Department of Nephrology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China,
Blood Purif. 2019;47 Suppl 1(Suppl 1):1-7. doi: 10.1159/000496217. Epub 2019 Jan 30.
This retrospective study aimed to investigate the clearance of magnesium (Mg) in peritoneal dialysis (PD) patients and its influencing factors.
The demographic information, clinical characteristics and laboratory data of the patients were collected. According to the corrected serum Mg (cS-Mg) concentration, patients were divided into 3 groups including hypomagnesemia (Mg2+ < 0.77 mmol/L, group A), normal serum Mg concentration (0.77 mmol/L ≤ Mg2+ ≤1.03 mmol/L, group B), and hypermagnesemia (Mg2+ > 1.03 mmo/L, group C).
One hundred and fifteen patients were enrolled, and their mean 24 h-peritoneal Mg clearance was 39.75 ± 17.42 mg. The mean normalized peritoneal Mg clearance rate was 1.82 ± 0.82 L/day/1.73 m2. Twenty-four-hour peritoneal Mg clearance of group A was significantly lower than that of group C (p < 0.05). Bivariate correlation analysis showed that cS-Mg was positively correlated with peritoneal dialysate Mg concentration (p < 0.01). cS-Mg was negatively correlated with the normalized peritoneal Mg clearance rate (p < 0.05). The normalized peritoneal Mg clearance rate was positively correlated with prealbumin (p < 0.05), daily peritoneal protein loss (p < 0.01) and the normalized PD-creatinine clearance rate (p < 0.01). The normalized peritoneal Mg clearance rate was also negatively correlated with the normalized renal-creatinine clearance rate (p < 0.01). Furthermore, cS-Mg of patients with continuous ambulatory PD (CAPD) was significantly lower than that of patients with daytime ambulatory PD (DAPD, p < 0.01). The normalized peritoneal Mg clearance rate of patients with CAPD was significantly higher than that of patients with DAPD (p < 0.01). Moreover, among the patients with different peritoneal transport characteristics of peritoneal equilibration test, the normalized peritoneal Mg clearance rate of high average transport patients was significantly higher than that in those with low transport, low average transport and high transport (p < 0.05).
Serum Mg could be partly cleared by PD. The peritoneal Mg clearance was positively related with serum Mg concentration, which was concentration-dependent. Peritoneal Mg clearance was negatively correlated with the residual renal function, while being positively correlated with the nutritional status and daily peritoneal protein loss. Peritoneal Mg clearance was higher in patients with high transport characteristics or CAPD.
本回顾性研究旨在探讨腹膜透析（PD）患者镁（Mg）的清除率及其影响因素。
收集患者的人口统计学信息、临床特征和实验室数据。根据校正后血清镁（cS-Mg）浓度，患者被分为 3 组，包括低镁血症（Mg2+<0.77mmol/L，组 A）、正常血清镁浓度（0.77mmol/L≤Mg2+≤1.03mmol/L，组 B）和高镁血症（Mg2+>1.03mmol/L，组 C）。
共纳入 115 例患者，其 24 小时腹膜 Mg 清除率的平均值为 39.75±17.42mg。归一化腹膜 Mg 清除率为 1.82±0.82L/天/1.73m2。组 A 的 24 小时腹膜 Mg 清除率明显低于组 C（p<0.05）。双变量相关分析表明，cS-Mg 与腹膜透析液 Mg 浓度呈正相关（p<0.01）。cS-Mg 与归一化腹膜 Mg 清除率呈负相关（p<0.05）。归一化腹膜 Mg 清除率与前白蛋白（p<0.05）、每日腹膜蛋白丢失（p<0.01）和归一化 PD-肌酐清除率（p<0.01）呈正相关。归一化腹膜 Mg 清除率与归一化肾肌酐清除率呈负相关（p<0.01）。此外，持续非卧床腹膜透析（CAPD）患者的 cS-Mg 明显低于日间非卧床腹膜透析（DAPD，p<0.01）。CAPD 患者的归一化腹膜 Mg 清除率明显高于 DAPD 患者（p<0.01）。此外，在腹膜平衡试验不同腹膜转运特征的患者中，高平均转运患者的归一化腹膜 Mg 清除率明显高于低转运、低平均转运和高转运患者（p<0.05）。
血清 Mg 可部分通过 PD 清除。腹膜 Mg 清除率与血清 Mg 浓度呈正相关，呈浓度依赖性。腹膜 Mg 清除率与残余肾功能呈负相关，而与营养状况和每日腹膜蛋白丢失呈正相关。具有高转运特征或 CAPD 的患者腹膜 Mg 清除率较高。
