女性骨面积大小与骨密度的关系

目的 了解女性骨面积大小(BAS)和骨矿物质密度(BMD)随年龄的变化趋势以及BAS与BMD的关系.方法采用Hologic QDR-2000双能X线吸收仪测量3390例20～84岁女性L1～L4后前位和左侧股骨近端(全髋部、股骨颈、大转子和转子间)骨矿物质含量(BMC)、BAS和BMD.结果L1～L4的BMC、BAS和BMD峰值均出现在30～34岁组,随后逐年下降,三者变化趋势一致;而股骨近端各部位BMC、BAS和BMD的变化趋势不同,BMC峰值出现在40～44岁组,BAS有随年龄增长逐渐增大的趋势,BMD峰值出现在20～24岁组.L1～L4的BAS与年龄呈负相关(r=0.362,P＜0.05);全髋部和大转子部位的BAS与年龄呈正相关,但相关系数较低;股骨颈和转子问的BAS与年龄不相关(P值均＞0.05).L1～L4(r=0.521)和近端全髋部(r=0.083)的BMD均与BAS呈正相关(P值均=0.000),股骨颈的BMD与BAS呈负相关(r=-0.102,P=0.000),大转子和转子间的BMD均与BAS不相关(P值均＞0.05).结论 使用面积BMD作为骨质疏松的诊断标准时,应该重视不同骨骼部位BAS的影响,是否使用体积BMD作为诊断标准是值得探讨的问题.

Correlation between bone area size and bone mineral density in females

Objective To study the age-related changes of bone area size(BAS)and bone mineral density (BMD)and to investigate the correlation between BAS and BMD in women.Methods The bone mineral content (BMC),BAS and BMD in the posteroanterior lumbar spine 1-4 and left proximal femur(including total hip, neck,troch and inter)were measured using Hologic QDR-2000 dual energy X-ray absorptiometry(DXA)in 3 390 women aged 20-84 years old.Results The peak values of BMC,BAS and BMD of lumbar spine 1-4 all occurred in patients of 30-34 years old and the then decreased with age,and change tendencies of the 3 parameters ware similar.The peak BMC of proximal femur occurred at 40-44 years old,BAS increased with age,BMD peak appeared at 20-24 years old.BAS of lumbar spine 1-4 was negatively correlated with age(r= -0.362,P<0.05),but BAS of the total hip and troch was positively correlated with age;meanwhile,no significant association was found at neck and inter.BMD was positively correlated with BAS in the lumbar spine 1-4 (r=0.521,P=0.000)and total hip(r=0.083,P=0.000),negative correlation was found between BMD and BAS at neck(r=-0.102),and BMD was not associated with BAS at troch and inter(all P>0.05). Conclusion When BMD is used as diagnosis standard of osteoporosis,the influences of BAS of different sites should be considered.Volumetric BMD as a diagnostic standard need to be further discussed.