各期慢性肾脏病患者腰椎定量CT骨密度与骨代谢指标的关系

摘要

目的：分析慢性肾脏病（CKD）1～5D期患者腰椎骨密度（BMD）与钙磷代谢、25羟维生素 D〔25（OH）D〕和骨转换生化标志物的关系。方法 CKD患者142例，根据估算肾小球滤过率（eGFR）及是否透析分为 CKD1～5D 期，腰椎定量 CT（QCT）测定患者 BMD，检测血白蛋白（ALB）、钙（Ca）、磷（P）、25（OH）D、全段甲状旁腺激素（iPTH）、碱性磷酸酶（ALP）、总I型前胶原氨基端延长肽（tPINP）、I型胶原羧基端肽β特殊序列（β-CTX）、骨钙素（OC），分析QCT-BMD与骨代谢相关指标关系。结果 BMD值、血ALB、Ca、ALP、25（OH）D 在 CKD1～5D各期之间均无统计学差异（P＞0.05）。＜70岁组，CKD5～5D期患者P高于CKD1～4期；CKD4～5D期患者tPINP高于CKD1～3期；CKD4～5期患者β-CTX高于CKD1～3期，CKD5D期患者高于CKD1～3及5期；CKD4～5期患者 OC、iPTH 均高于 CKD1～3期，CKD5D 期患者高于 CKD1～5期（P＜0.05）。≥70岁组， CKD5D期患者血P高于CKD1～5期；CKD5期患者tPINP、OC均高于CKD1～4期，CKD5D期高于CKD1～5期；CKD5～5D期患者β-CTX高于CKD 1～4期；CKD5期患者iPTH高于CKD1～4期，CKD5D期患者高于CKD2～3期（P＜0.05）。 BMD值与eGFR、Ca、P、25（OH）D及骨转换生化标志物无相关性（P＞0.05）。 eGFR与P、tPINP、β-CTX、OC、iPTH呈负相关（P＜0.01）。多因素Logistic回归分析CKD骨质疏松或CKD-MBD伴低BMD的独立危险因素为年龄（≥70岁），性别（女性）和血钙水平（高钙血症）。结论维持正常血钙对于CKD骨质疏松或低BMD非常重要。%Objective To analyze the relationship between spinal bone mineral density and calcium and phosphorus metabolism ,25 hydroxyvitamin D〔25(OH)D〕,and biochemical markers of bone turnover (BMT)in patients with chronic kidney disease (CKD).Methods 142 CKD patients were divided into stages CKD 1~5D according to the eGFR and dialysis .The spinal BMD was measured by quantitative CT (QCT),serum calcium(Ca),phosphorus(P),25(OH)D,intact parathyroid hormone(iPTH),alkaline phosphatase(ALP),total procollagen type I propeptides(tPINP),β-crosslaps(β-CTX),osteocalcin(OC)were tested.Results In the group(<70 years old),the levels of serum phosphorus in stages CKD5~5D were increased compared with that of stages CKD 1~4,the levels of tPINP in stages CKD4~5D were in-creased compared with those of stages CKD 1~3;the levels of β-CTX in stages CKD4~5 were increased compared with those of stages CKD 1~3,and it was increased in stage CKD5D compared with those of stages CKD1~3 and 5;the levels of OC and iPTH in stages CKD4~5 were increased compared with those of stages CKD 1~3,and it was increased of stage CKD5D compared with that of stages CKD1~5(P<0. 05).In another group(≥70 years old),the level of serum phosphorus in stage CKD5D was increased compared with that of stages CKD 1~5;the levels of tPINP and OC in stage CKD5 were increased compared with those of stages CKD1 ~4,and they were increased in stage CKD5D compared with those of stages CKD1~5;the levels of β-CTX in stages CKD5~5D were increased compared with those of stage CKD1~4;the level of iPTH in stage CKD5 was increased compared with that of stages CKD 1~4,and it was increased of stage CKD 5D com-pared with that of stages CKD1~3 and 5(P<0.05).BMD values versus eGFR,Ca,P,25(OH)D and BMT showed no correlation (P>0.05). The eGFR versus serum phosphorus,tPINP,β-CTX,OC and iPTH showed negatively correlation (P<0.01).According to the multi-factor lo-gistic regression analysis,the independent risk factors of osteoporosis in CKD /CKD-MBD with low BMD were advanced age (≥70),gender (female)and blood calcium level(hypercalcemia).Conclusions There is great important clinical significance to maintain normal blood cal-cium in CKD with osteoporosis and low BMD .