围绝经期女性骨生化指标与骨密度的相关性分析

目的分析40～60岁女性不同年龄段的血清中总I型前胶原氨基端肽（procollagen Ⅰ N-terminal peptide,PINP）、β-胶原降解产物（β-Crosslaps）、N端骨钙素（N-MID）及甲状旁腺素（parathyroid hormone,PTH）的变化规律,以及这几项骨转换指标与骨密度（bone mineral density,BMD）的相关性。方法①骨生化指标测定：上午8～9点空腹抽取肘静脉血4 ml,即时分离血清,采用电化学发光免疫分析法分析血清中PINP、β-Crosslaps、N-MID及PTH的含量。②骨密度测定：采用美国GE公司生产的Lunar Prodigy双能X线骨密度测定仪（dual energy X-ray absorptiometry,DEXA）,检测各部位BMD。结果①40～44岁年龄段妇女血清中PINP、β-Crosslaps及N-MID相对较低,45～49岁年龄段PINP、β-Crosslaps开始明显升高（P〈0.05）,而50～54岁年龄段又较45～49岁年龄段有明显的上升（P〈0.05）,N-MID只在50～54年龄段较前一年龄段明显上升（P〈0.05）,随后三个指标都在55～60岁年龄段出现小幅回落;四个年龄段间妇女血中PTH有随年龄而升高的趋势,但各组间皆无显著差异（P〉0.05）。②PINP与腰椎1～4（L1～L4）的BMD呈负相关（P〈0.05）;β-Crosslaps、N-MID与L1～L4、Ward’s以及Troch的BMD均呈显著负相关（P均〈0.05）;PTH与各部位的BMD无明显相关性（P〉0.05）。③所测各区域,与正常骨量组比较,低骨量组及骨质疏松组妇女的PINP、β-Crosslaps均显著升高（P〈0.05）;低骨量组[除左侧股骨颈（femeralneck,FN）部位外]及骨质疏松组妇女的N-MID显著升高（P〈0.05）;低骨量组妇女L1-L4及FN区域的PTH显著升高（P〈0.05）,骨质疏松组妇女所测所有区域的PTH均显著上升（P〈0.05）。结论高骨转换状态是围绝经期女性骨量丢失的重要原因。PINP、β-Crosslaps、N-MID及PTH在反映围绝经期女性随年龄变化的骨转换上具有较强的敏感性和特异性,监测这几个指标有助于早期防治骨质疏松症。

Correlation Study on Bone Mineral Density and Bone Biochemical Markers of Perimenopausal Women

Objective To analyse the changes of serum procollagen I N-terminal peptide（PINP）,β-Crosslaps,N-MID osteocalcin（N-MID） and parathyroid hormone（PTH） in perimenopausal women of 40-60 years of age,as well as their correlations with bone mineral density（BMD）.Methods ①Test of bone biochemical indexes： 4ml elbow venous blood was extracted between 8-9 am before meal,the serum was immediately separated,and levels of PINP,β-Crosslaps,N-MID and PTH were tested by electrochemiluminescence immunoassay.②BMD of lumbar spine L1-L4,femoral neck,wards and troch were measured by American GE company＇s Lunar Prodigy dual energy X ray（DEXA） bone density meter.Results ①The serum PINP,β-Crosslaps and N-MID levels in the 40-44 group were relatively low,and the serum PINP and β-Crosslaps levels in the 45-49 group and 50-54 group were significantly higher than those in the previous younger age group respectively（P0.05）.Serum N-MID levels were increased significantly in the 50-54 group than the previous age group.All the three makers decreased slightly in the 55-60 group than the 50-54 group.There was no significant difference in PTH among the four groups（P0.05）.② PINP was negatively correlated with BMD of L1-L4（P0.05）.There was negative correlation among β-Crosslaps,N-MID and BMD of L1-L4,Ward＇s and Troch（P0.05）.PTH has no significant correlation with BMD（P0.05）.③Compared with the normal group,PINP and β-Crosslaps of the low bone mass and osteoporosis group,the N-MID of low bone mass group（except in femeralneck） and osteoporosis group, PTH at L1-L4 and femeralneck ofthe low bone mass group,and PTH of osteoporosis group were significantly higher（all P0.05）.Conclusion High bone turnover is an important cause of bone loss in perimenopausal women.PINP,β-Crosslaps,N-MID and PTH are sensitive and specific bone biochemical markers for the bone turnover change with age in perimenopausal women.Monitoring these indicators help the prevention and early treatment of osteoporosis.