降低透析液钙浓度对慢性肾脏病-矿物质骨代谢异常的影响

Influence of lowering dialysate calcium concentration on chronic kidney disease-mineral and bone disorder in maintenance hemodialysis patients

目的探讨降低透析液钙浓度对维持性血液透析患者慢性肾脏病-矿物质骨代谢异常(CKD-MBD)各项评估指标和相关药物使用的影响,初步了解1.25 mmol/L钙浓度透析液的适用人群。方法回顾性分析四川大学华西医院血液透析中心门诊透析患者在透析液钙浓度由1.5 mmol/L调低为1.25 mmol/L后的1年中的临床资料,比较透析液钙浓度调整前后血清钙、磷、甲状旁腺素(PTH)、碱性磷酸酶等CKD-MBD评估指标的检测值和达标情况以及钙剂和骨化三醇的使用剂量。依据基线PTH值对CKD-MBD患者进行分组分析,评价低钙透析液对各组患者继发性甲状旁腺功能亢进的影响。结果共纳入281例透析患者,透析液钙浓度降低后血钙和血磷水平无明显变化(P>0.05),PTH和碱性磷酸酶水平明显增高(P<0.05)。1.25 mmol/L钙浓度透析液使用1年后和使用前比较,血钙和血磷的达标率差异无统计学意义(P>0.05),而PTH达标率由56.1%下降至49.8%,差异有统计学意义(P<0.05)。透析液钙浓度调整后患者每周的碳酸钙使用剂量无明显变化(P>0.05),而骨化三醇的使用量由(1.87±1.09)μg/周明显增加为(2.62±1.26)μg/周(P<0.05)。不同PTH基线值分组的患者对1.25 mmol/L钙浓度透析液的反应不同,基线PTH>300 ng/L的分组在药物调控后有59.5%患者PTH值高于目标值上限,较基线情况明显增加(P<0.05)。结论 1.25 mmol/L钙浓度的透析液相较于1.5 mmol/L钙浓度的透析液对血清钙和磷的水平无明显影响,但可引起PTH的升高,诱发或加重继发性甲状旁腺功能亢进和高转运性骨病;基线PTH值较低的患者使用低钙透析液后可能获益更多,为更适宜人群。

Objective To explore the influence of lowering dialysate calcium concentration on the parameters of chronic kidney disease(CKD）-mineral bone disorder(MBD） and drug dosage of maintenance hemodialysis patients,and find out the target group of the dialysate calcium concentration 1. 25. Methods The clinical data of maintenance hemodialysis patients in our hospital were analyzed retrospectively. The observation period was set as consecutive 12 months after the Ca concentration decreased from 1. 5 to 1. 25 mmol/L. The serum levels of calcium,phosphate,PTH and alkaline phosphatase before and after Ca conversion were compared. The effect of lowering Ca on theprescription of calcium carbonate and calcitriol was also determined. Patients were further divided into three groups according to their baseline PTH level to evaluate the impact of Ca 1. 25 on secondary hyperparathyroidism. Results 281 patients were finally enrolled in this study. During the first year after Ca conversion,mean serum calcium and phosphate levels did not change significantly(P 〉0. 05）,while alkaline phosphatase and PTH concentrations increased(P〈 0. 05）. The rate of achievement of target serum calcium and phosphate one year after lowering Ca was not different from that at baseline(P〉 0. 05）. However,the rate of achievement of target PTH dropped from 56. 1 %to 49. 8 % and this difference was considered statistically significant(P〈 0. 05）. The dose of calcium carbonate did not change after the Ca conversion(P〉 0. 05）,while average calcitriol dose increased from(1. 87 ± 1. 09） to(2. 62 ± 1. 26） μg/week obviously(P 〈0. 05）. Serum PTH level increased over time independent of baseline PTH. But the group with highest baseline PTH(〉300 ng/L） tended to exceed the upper limit of PTH target range after the Ca conversion(59. 5 %）.Conclusions Compared to Ca 1. 5,Ca 1. 25 hardly causes change on serum calcium and phosphate level. However,it can increase PTH level,consequently leading to secondary hyperparathyroidism and high turnover renal osteodystrophy may be exacerbated. Patients with lower baseline serum PTH level are likely to benefit from Ca 1. 25.