绝经后女性促甲状腺激素生理变异对骨密度和骨质疏松症的影响研究

Effect of Physiological Variations of Thyroid Stimulating Hormone on Bone Mineral Density and Osteoporosis in Postmenopausal Women

目的探讨甲状腺功能正常的绝经后女性促甲状腺激素(TSH)水平参考范围内的波动对骨密度、骨质疏松症的影响。方法选取2009年11月—2010年2月参与贵阳市社区居民健康调查的甲状腺功能正常的绝经后女性234例为研究对象。检测受试者甲状腺功能、维生素D、甲状旁腺激素(iPTH)、血钙、血磷水平;采用双能X线骨密度仪测量左侧股骨颈、L1~4、全髋、大转子、ward三角区骨密度。根据TSH水平,以三分位数将受试者分为3组,即Q1组(0.73~2.67 mU/L)、Q2组(2.68~3.83 mU/L)、Q3组(3.84~6.14 mU/L),各78例。结果各组股骨颈、全髋、大转子、ward三角区骨密度及股骨颈骨密度T值比较,差异均有统计学意义(P<0.05);其中,Q2组大转子骨密度高于Q1组,Q3组股骨颈、全髋、ward三角区骨密度高于Q1组,Q3组股骨颈骨密度T值高于Q1、Q2组(P<0.05)。TSH水平与股骨颈、全髋、ward三角区骨密度呈正相关(r=0.17、0.14、0.16,P<0.05)。多元线性回归分析显示,校正年龄、绝经年限、BMI、维生素D、iPTH后,TSH水平与股骨颈骨密度(b=0.012,b'=0.134)、wards三角区骨密度(b=0.013,b'=0.125)独立相关(P<0.05)。各组股骨颈骨量减少检出率比较,差异有统计学意义(P<0.05);其中,Q3组股骨颈骨量减少检出率低于Q1组、Q2组(P<0.016)。结论甲状腺功能正常的绝经后女性TSH水平参考范围内波动可能会对股骨颈、全髋、ward三角区骨密度产生一定的影响,并且TSH水平可能是股骨颈、ward三角区骨密度的独立影响因素,低TSH水平者有更高的骨量减少发生率。

Objective To investigate the effect of the fluctuation of thyroid stimulating hormone（ TSH） level in the normal range on the bone mineral density（ BMD） and osteoporosis of postmenopausal women with normal thyroid function.Methods 234 postmenopausal women with normal thyroid function who participated in the health survey of community residents in Guiyang from November 2009 to February 2010 were selected as the research objects. The thyroid function, vitamin D,parathyroid hormone（ iPTH）,serum calcium,and serum phosphorus levels of the subjects were detected; the BMD of left femoral neck,L（1-4）,total hip,greater trochanter,and ward triangle were measured by dual energy X- ray bone sonometers.According to the TSH level,subjects were divided into 3 groups by tri- sectional quantile method： group Q1（ 0.73- 2.67 mU/L）,group Q2（ 2.68- 3.83 mU/L）,group Q3（ 3.84- 6.14 mU/L）,78 cases in each group. Results The BMD of the femoral neck,total hip,greater trochanter,and ward triangle,and the T value of the BMD of the femoral neck in these groups were significantly different（ P 0.05）. The BMD of greater trochanter in group Q2 was higher than that in group Q1,the BMD of the femoral neck,total hip,and ward triangle in group Q3 was higher than that in group Q1,and the T value of the BMD of the femoral neck in group Q3 was higher than that in group Q1 and Q2（ P〈0.05）. There was a positive correlation between the TSH level and BMD of femoral neck,total hip and ward triangle（ r = 0.17,0.14,0.16, P 0.05）. Multivariate linear regression analysis showed that TSH level and the BMD of femoral neck（ b=0.012,b＇ =0.134） and ward triangle（ b =0.013,b＇ = 0.125） were independently related after correcting age, menopausal years, BMI, vitamin D and iPTH,（ P〈0.05）.There was significant difference in the detection rate of osteopenia in femoral neck（ P〈0.05）. Among them,the detection rate of osteopenia in femoral neck in group Q3 was lower than that in group Q1 and Q2（ P〈0.016）. Conclusion The physiological variation of THS level of postmenopausal women with normal thyroid function may have certain effect on BMD of the femoral neck,total hip, and ward triangle. Moreover, the TSH level may be the independent influencing factor of femoral neck and ward triangle,and low level of TSH is associated with a higher incidence of osteopenia.