Tracy J Kathleen, Meyer Walter A, Flores Raymond H, Wilson P David, Hochberg Marc C
Department of Epidemiology and Preventive Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA.
J Bone Miner Res. 2005 Jul;20(7):1228-34. doi: 10.1359/JBMR.050310. Epub 2005 Mar 14.
Older black men have higher adjusted BMD than older white men. Using data from a longitudinal cohort study of older men followed for a mean of 18.8 +/- 6.5 (SD) months, we found that older black men have a higher rate of decline in femoral neck and total hip BMD and femoral neck BMAD than older white men.
Older black men have higher adjusted BMD compared with older white men. The difference in BMD may be caused by having attained higher peak bone mass as young adults and/or having a slower rate of decline in bone mass as adults. There are few published longitudinal data on change in bone mass in older white men and no published data for older black men.
Three hundred forty-nine white men and 119 black men 65 of age (mean age, 75 +/- 5.7 and 72 +/- 5.6 years, respectively) who participated in the longitudinal component of the Baltimore Men's Osteoporosis Study returned for a second visit after a mean of 18.8 +/- 6.5 (SD) months and were not taking medications used to treat low bone mass at either visit. BMD was measured at the femoral neck and total hip by Hologic-certified technicians using a QDR 2000 at the baseline visit (V1) and QDR 4500 at the first follow-up visit (V2). Participants also completed self-administered and interviewer-administered questionnaires and underwent standardized clinic examinations. Bone mineral apparent density (BMAD) at the femoral neck was calculated as an estimate of volumetric BMD. Annual crude and multiple variable adjusted percent changes in BMD and BMAD were calculated.
In univariate analyses, black men had lower percent decline in femoral neck and total hip BMD and femoral neck BMAD than white men. In addition, older age at baseline, lower baseline weight, current smoking, and lower baseline BMD were associated with greater percent decline per year in femoral neck BMD; older age at baseline, current smoking, and lower baseline BMD were associated with greater percent decline per year in total hip BMD; and older age at baseline and lower baseline femoral neck BMAD were associated with greater percent decline per year in femoral neck BMAD. Racial differences in bone loss persisted in multiple variable models that controlled for other factors associated with change in BMD and BMAD.
Older black men seem to lose bone mass at a slower rate than older white men. These differences in the rate of bone loss may account, in part, for the racial disparities in BMD and BMAD and risk of osteoporotic fractures among older men.
老年黑人男性经调整后的骨密度高于老年白人男性。利用一项针对老年男性的纵向队列研究的数据，该研究平均随访了18.8±6.5（标准差）个月，我们发现老年黑人男性股骨颈、全髋骨密度及股骨颈骨矿表观密度（BMAD）的下降速率高于老年白人男性。
与老年白人男性相比，老年黑人男性经调整后的骨密度更高。骨密度差异可能是由于年轻时达到了更高的峰值骨量和/或成年后骨量下降速率较慢所致。关于老年白人男性骨量变化的纵向数据鲜有发表，而老年黑人男性则尚无相关发表数据。
349名白人男性和119名65岁及以上的黑人男性（平均年龄分别为75±5.7岁和72±5.6岁）参与了巴尔的摩男性骨质疏松症研究的纵向部分，在平均18.8±6.5（标准差）个月后再次就诊，且两次就诊时均未服用用于治疗低骨量的药物。在基线访视（V1）时，由霍洛维茨认证的技术人员使用QDR 2000测量股骨颈和全髋的骨密度，在首次随访访视（V2）时使用QDR 4500测量。参与者还完成了自行填写和由访谈员填写的问卷，并接受了标准化的临床检查。计算股骨颈的骨矿表观密度（BMAD）作为体积骨密度的估计值。计算骨密度和BMAD的年度粗变化率和多变量调整变化率。
在单变量分析中，黑人男性股骨颈和全髋骨密度以及股骨颈BMAD的下降百分比低于白人男性。此外，基线年龄较大、基线体重较低、当前吸烟以及基线骨密度较低与股骨颈骨密度每年更大的下降百分比相关；基线年龄较大、当前吸烟以及基线骨密度较低与全髋骨密度每年更大的下降百分比相关；基线年龄较大和基线股骨颈BMAD较低与股骨颈BMAD每年更大的下降百分比相关。在控制了与骨密度和BMAD变化相关的其他因素的多变量模型中，骨丢失的种族差异仍然存在。
老年黑人男性似乎比老年白人男性的骨量丢失速率更慢。这些骨丢失速率的差异可能部分解释了老年男性在骨密度和BMAD以及骨质疏松性骨折风险方面的种族差异。
