腹膜透析患者血清钙、磷及甲状旁腺激素的最佳范围值研究

The optimal ranges of serum calcium, phosphorus and intact parathyroid hormone in peritoneal dialysis patients

目的探讨腹膜透析患者血清钙、磷以及甲状旁腺激素最佳范围值。方法本研究为单中心回顾性队列研究，纳人本透析中心自2008年1月1日至2016年4月30日开始透析的217例腹膜透析患者，随访终点至2016年12月31日。分析患者的血钙、血磷及全段甲状旁腺激素（iPTH）与全因死亡的相关性，收集患者基线和开始透析后每3个月的临床信息进行分析。结果Kaplan-Meier生存分析结果显示，不论基线值或平均值，将患者的血清钙、磷以及iPTH按KDOQI或KDIGO指南进行分组分析，患者组间的生存率差异无统计学意义。Cox模型和三次样条（cubic splines）分析结果显示，死亡风险最低的血清钙离子范围在2．17～2．40mmol／L，血磷范围在1．20～1．67mmol／L，iPTH范围在180～350ng／L。结果还发现，时间平均值而非基线值在上述范围之内和之外的患者的生存曲线差异有统计学意义，提示上述指标的平均值控制达标比基线值更重要。结论本透析中心的结果提示应将腹膜透析患者血清钙、磷及iPTH的平均值分别控制在以下范围：钙为2．17～2．40mmol／L，磷为1．20～1．67mmol／L，iPTH为180～350ng／L。该范围还需要大样本研究进一步证实。

Objective To explore the optimal levels of serum calcium, phosphorus and intact parathyroid hormone （iPTH） in peritoneal dialysis （PD） patients. Methods This study is a single center, retrospective cohort study. The associations between serum calcium, phosphorus and iPTH and all-cause mortality in 217 PD patients were analyzed. All patients started PD between January 1, 2008 and April 30, 2016 were enrolled and followed up to December 31, 2016. At baseline and every 3 months, biochemical and therapeutic information was collected. Cox proportional hazard regression models and cubic splines analysis were employed to assess the lowest mortality risk ranges in serum markers of bone metabolism. Results There was no significantly difference between patients within target ranges based on KDOQI or KDIGO guideline and those outside the target ranges by Kaplan- Meier survival analysis. The lowest mortality risk ranges were 2.17-2.40 mmol/L for serum calcium, 1.20-1.67 mmol/L for serum phosphorus and 180-350 ng/L for serum iPTH by using Cox models and cubic splines analysis. Moreover, cumulate survival had significant difference between patients within the descriptive ranges and those out of the descriptive ranges at timeaveraged values but not at baseline values. Conclusions The optimal timeaveraged ranges of PD patients are 2.17-2.40 mmol/L for serum calcium, 1.20-1.67 mmol/L for serum phosphorus and 180-350 ng/L for serum iPTH. These ranges need further validation by large population studies to further conform.