慢性肾脏病患者血清甲状旁腺激素和甲状旁腺激素相关蛋白水平与肌肉减少症的相关性分析

Correlation of Serum Parathyroid Hormone and Parathyroid Hormone-Related Protein with Sarcopenia in Patients with Chronic Kidney Disease

摘要: 目的：探讨慢性肾脏病(chronic kidney disease, CKD)患者血清甲状旁腺激素(parathyroid hormone, PTH)和甲状旁腺激素相关蛋白(parathyroid hormone-related protein, PTHrP)水平与肌肉减少症(肌少症)的相关性。方法：本研究为单中心横断面研究，收集来自2023年12月至2024年6月期间在广州市红十字会医院的CKD 1~5期住院患者及2023年9月至2023年12月在血液净化中心接受血液透析治疗患者的临床资料、血清全段甲状旁腺激素(intact parathyroid hormone, iPTH)、PTHrP以及生化指标，并测量其身高、体重、握力、捏力等指标，采用人体成分分析仪测量人体成分指标。根据亚洲肌少症工作组的诊断标准将患者分为肌少症组与非肌少症组。采用独立样本t检验、Mann-Whitney U检验、单因素方差分析、Kruskal-Wallis H检验及χ²检验比较不同分组间数据的差异。Spearman相关分析、线性回归、logistic回归法分析CKD患者iPTH、PTHrP与肌少症相关指标的相关性。结果：本研究共纳入150例患者，平均年龄67.27 ± 10.52岁。CKD人群的总体肌少症患病率为22%，其中CKD 1~4期为16.00%，CKD 5期(未透析)为18.00%，MHD患者高达32.00%。与非肌少症组患者相比，肌少症组患者拥有较高血磷水平，较低BMI、握力、捏力、四肢骨骼肌质量指数(ASMI)、骨骼肌质量、瘦体重、相位角。相关性分析显示血清iPTH与脂肪量呈负相关，血清PTHrP与ASMI呈正相关(P值 < 0.05)。单因素logistic回归分析表明BMI (OR = 0.84; 95% CI: 0.75, 0.92; P < 0.001)是肌少症发生的保护因素，血磷(OR = 2.14; 95% CI: 1.07, 4.33; P = 0.03)、iPTH (OR = 1.02; 95% CI: 1.01, 1.04; P = 0.01)是肌少症发生的独立危险风险，多因素二元logistic回归分析发现BMI (OR = 0.81; 95% CI: 0.72, 0.91; P < 0.001)与肌少症的发生独立相关，但iPTH (OR = 1.01; 95% CI: 0.99, 1.04; P = 0.29)与肌少症无关。多因素线性回归分析发现iPTH每增加一个单位(pmol/L)捏力的水平下降0.03 kg (β = −0.03; 95% CI: −0.053, −0.007; P = 0.01)。多因素logistic分析发现，iPTH每增加一个单位(pmol/L)，肌少症发生风险增加3% (OR = 1.03; 95% CI: 1.00, 1.05; P = 0.03)。结论：CKD患者肌少症高发，且透析后加重。血清iPTH与肌少症指标存在负相关关系，血清iPTH的升高可使捏力下降，并增加肌少症的风险，提示iPTH可能是肌少症的一个重要指标。

Abstract: Objective: To investigate the association between serum levels of parathyroid hormone (PTH) and parathyroid hormone-related protein (PTHrP) and sarcopenia in patients with chronic kidney disease (CKD). Methods: This was a single-center cross-sectional study. Clinical data, serum intact parathyroid hormone (iPTH), PTHrP, and biochemical parameters were collected from hospitalized patients with CKD stages 1~5 at Guangzhou Red Cross Hospital between December 2023 and June 2024, as well as from patients undergoing hemodialysis at the Blood Purification Center between September 2023 and December 2023. Anthropometric parameters, including height, weight, grip strength, and pinch strength, were measured, and body composition indices were assessed using a body composition analyzer. Patients were classified into the sarcopenia group and the non-sarcopenia group according to the diagnostic criteria of the Asian Working Group for Sarcopenia. Differences in data between groups were compared using an independent samples t-test, Mann-Whitney U test, one-way ANOVA, Kruskal-Wallis H test, and chi-square test. Spearman correlation analysis, linear regression, and logistic regression were used to analyze the associations of iPTH and PTHrP with sarcopenia-related parameters in CKD patients. Results: A total of 150 patients were enrolled in this study, with a mean age of 67.27 ± 10.52 years. The overall prevalence of sarcopenia in the CKD population was 22%, with rates of 16.00% in CKD stages 1~4, 18.00% in CKD stage 5 (non-dialysis), and as high as 32.00% in maintenance hemodialysis patients. Compared with the non-sarcopenia group, patients in the sarcopenia group had higher serum phosphorus levels and lower BMI, grip strength, pinch strength, appendicular skeletal muscle mass index (ASMI), skeletal muscle mass, lean body mass, and phase angle. Correlation analysis showed that serum iPTH was negatively correlated with fat mass, while serum PTHrP was positively correlated with ASMI (all P < 0.05). Univariable logistic regression analysis indicated that BMI (OR = 0.84; 95% CI: 0.75, 0.92; P < 0.001) was a protective factor against sarcopenia, while serum phosphorus (OR = 2.14; 95% CI: 1.07, 4.33; P = 0.03) and iPTH (OR = 1.02; 95% CI: 1.01, 1.04; P = 0.01) were independent risk factors for sarcopenia. Multivariable binary logistic regression analysis found that BMI (OR = 0.81; 95% CI: 0.72, 0.91; P < 0.001) was independently associated with the occurrence of sarcopenia, but iPTH (OR = 1.01; 95% CI: 0.99, 1.04; P = 0.29) was not associated with sarcopenia. Multivariable linear regression analysis revealed that for each unit (pmol/L) increase in iPTH, pinch strength decreased by 0.03 kg (β = −0.03; 95% CI: −0.053, −0.007; P = 0.01). Multivariable logistic regression analysis showed that for each unit (pmol/L) increase in iPTH, the risk of sarcopenia increased by 3% (OR = 1.03; 95% CI: 1.00, 1.05; P = 0.03). Conclusions: The prevalence of sarcopenia is high in patients with CKD and worsens after dialysis. Serum iPTH is negatively correlated with sarcopenia indicators. Elevated serum iPTH may lead to decreased pinch strength and increased risk of sarcopenia, suggesting that iPTH may be an important indicator for sarcopenia.