骨代谢标志物检测在类风湿性关节炎患者继发骨质疏松症中的意义

目的：探讨骨代谢标志物总I型胶原氨基端延长肽（total N-terminal propeptide of type I procollagen， TPINP）、β-胶原降解产物（β-collagen specific sequences，β-CTx）和骨钙素N端中分子（N-terminal-midfragment of osteocalcin， N-MID）片段检测在类风湿性关节炎（rheumatoid arthritis， RA）继发骨质疏松症（osteoporosis， OP）中的意义。方法采用双能X线吸收法测定70例RA患者和60例正常对照者股骨和腰椎部位骨密度（bone mineral density， BMD），所有受试者均采用电化学发光免疫法测定血清TPINP、β-CTx和N-MID的浓度。比较两组间OP发生率、三项骨代谢标志物浓度的差异以及RA患者组中RA并非OP 组与RA 并OP 组之间骨代谢标志物浓度的差异。结果 RA 患者OP 发生率（37．1％）高于对照组（11．7％），且差异具有统计学意义（χ2＝11．07，P＜0．05）。 RA患者中TPINP明显低于对照组（t＝2．47，P＜0．05）；N-MID也明显低于对照组（t＝5．26，P＜0．05），而β-CTx则明显高于对照组，差异具有统计学意义（t＝2．83，P＜0．05）。 TPINP和N-MID在RA并非OP组与RA并OP组之间差异均无统计学意义（t＝0．69，t＝0．58，P均＞0．05），而β-CTx在两组间差异有统计学意义（t＝3．09，P＜0．05）。结论血清骨代谢标志物检测在RA和RA继发OP的诊断和治疗中具有重要的临床意义。

Evaluation of bone turnover markers in rheumatoid arthritis patients with osteoporosis

Objective To investigate the incidence of osteoporosis（OP） in rheumatoid arthritis（RA） patients by monitoring total N-terminal propeptide of type I procollagen （TPINP）, β-collagen specific se-quences （β-CTx） and N-terminal-midfragment of osteocalcin （N-MID） in serum. Methods Bone mineral density （BMD） of 70 cases of RA inpatients and 60 cases of volunteers were measured by dual-energy X-ray absorptionmetry. The serum TPINP, β-CTx and N-MID were measured by electrochemiluminescence im-munoassay. The incidence of OP, bone turnover markers in RA patients and volunteers, bone turnover markers in the RA patients with or without OP were evaluated. Results The incidence of OP in RA patients group was significantly higher than that of control group, and difference had statistical significance（χ2=11.07, P＆lt;0.05）. Compared with control group, the levels of TPINP and N-MID in RA patients were obviously decreased, but the level ofβ-CTx was dramatically increased and the differences all had statistical significance （Pall＆lt;0.05）. There was no statistical significance in the differences for TPINP and N-MID between RA patients with OP and without OP（t=0.69, t=0.58, Pall＆gt;0.05）, exceptβ-CTx（t=3.09, P＆lt;0.05）. Conclusion The measurement of the serum TPINP,β-CTx and N-MID levels are helpful for evaluating the incidence of OP in RA patients.