Levels and correlations of serum bone metabolism markers in patients with chronic kidney disease

Abstract

Objective To analyze serum levels of bone metabolism markers in patients with chronic kidney disease (CKD).

Methods Totally 544 CKD patients visited in the department of nephrology the First Affiliated Hospital of Dalian Medical University and Dalian Firendship Hospital from 2014 to 2018 were selected as the cases and 577 healthy volunteers were recruited as the controls. Serum levels of bone metabolic markers in the cases and the controls were measured and the detection results of the cases at different CKD stage (stage I CDK [CKD-1] – stage V CDK [CKD-5]) were compared to those of the controls.

Results Compared with that in the controls, decreased 25-hydroxyvitamin D (25(OH)D) was detected in the cases of CKD-1 – CKD-5 phase (all P < 0.05), especially in the cases of CKD-2, CKD-4, and CKD-5 ( P < 0.01 for all). Increased serum N-terminal midfragment of osteocalcin (N-MID), total type I procollagen amino terminal prolongation peptide (tPINP), and calcitonin (CT) were detected in the cases of CKD-4 ( P < 0.05 for all) and in the cases of CKD-5 ( P < 0.01). Significantly increased specific sequence of β-collagen (β-CTX) was detected in the cases of CKD-4 and CKD-5 (both P < 0.01). Correlation analyses revealed that 25(OH)D was positively correlated with calcium (Ca) and alkaline phosphatase (ALP) in the cases ( r > 0, P < 0.01); N-MID, β-CTX, and CT were positively correlated with phosphorus (P) and parathyroid hormone (iPTH) ( r > 0, P < 0.01); tPINP was positively correlated with Ca ( r > 0, P < 0.01) and CT was correlated with Ca reversely ( r < 0, P < 0.05).

Conclusion Serum 25(OH)D level is lower in all CKD patients than in healthy people; but serum N-MID increased obviously in stage VI – stage V CKD patients.

Abstract

【摘 要】 目的 分析骨代谢标志物在慢性肾脏病（CKD）患者中血清水平。 方法 抽取 2014 — 2018 年大连医科大学附属第一医院和大连市友谊医院就诊的 CKD 患者 544 例作为病例组，选取同期健康志愿者 577 人作为对照组。分别测定病例组与对照组骨代谢标志物的血清水平。 结果 CKD 共分 5 期，分别与对照组比较，25 羟维生素 D [25（OH）D]均减少（ P均 < 0.05），CKD-2、CKD-4 和 CKD-5 期减少更加明显（ P均 < 0.01）。N 端骨钙素（N-MID）、总 I 型前胶原氨基端延长肽（tPINP）、血清降钙素（CT）在 CKD-4 期升高（ P均 < 0.05），CKD-5 期升高更加明显（ P均 < 0.01）。β 胶原特殊序列（β-CTX）在 CKD-4 和 CKD-5 期明显升高（ P均 < 0.01）。相关分析显示 CKD 患者 25（OH） D 与钙（Ca）、碱性磷酸酶（ALP）呈正相关（ r均 > 0， P均 < 0.01），N-MID、β-CTX、CT 分别与磷（P）、甲状旁腺激素（iPTH）呈正相关（ r均 > 0， P均 < 0.01），tPINP 与 Ca 呈正相关（ r > 0， P < 0.01），CT 与 Ca 呈负相关（ r < 0， P < 0.05）。 结论 CKD 共 5 期患者血清 25（OH）D 水平均低于健康人，CKD-4、CKD-5 期患者血清 N-MID 水平明显升高。