随增龄不同骨骼部位骨密度减少的性别差异

Gender differences in bone mineral density at various skeletal regions and age-related bone loss in the elderly

目的 了解随增龄骨密度（BMD）减少的性别差异。方法 采用双能X线（DXA）骨密度仪，测量1133例（女性796例，男性337例）60～84岁的老年志愿者腰椎正位（L1～L4）、腰椎侧位（L2-L4）、髋部和前臂远端的BMD。结果 女性股骨颈和前臂远端1／3处的BMD与年龄分别呈3次回归模型和线性回归模型关系，女性其他骨骼部位及男性所有骨骼部位的BMD与年龄均呈复合曲线模型关系；女性不同骨骼部位的BMD平均累积丢失（20．5±8．5）％，范围-32．5％～-9．6％，男性丢失（10．9±4．7）％，范围-18．9％～-5．1％。BMD丢失最多的骨骼部位是前臂远端，女性和男性分别丢失32．5％和18．9％。老年女性各骨骼部位BMD平均每10年减少8．6％，男性减少4．5％。结论 老年人各骨骼部位BMD的丢失存在性别差异；衰老所致的骨丢失率，女性高于男性。髋部和前臂远端是老年人骨丢失的敏感部位，测量这两个骨骼部位，将有利于老年人低骨量和骨质疏松的检出率。

Objective To explore the gender difference in the bone mineral density （BMD） loss with ageing in the elderly. Methods A dual-energy X-ray absorptiometry （DXA） bone densitometer was used to measure BMDs at the posteroanterior and lateral positions of spine, hip and distal forearm in 1 133 （796 women and 337 men） senior volunteers aged 60-84 years. Results The relationship between BMD and age presented cubic and linear regression model at femoral neck and 1/3 site of radius＋ ulna respectively in females, but compound curve model at the rest of skeletal regions in females and at all skeletal sites in males. From 60 to 84 years old, average accumulated BMD loss rate （ABLR） was （20.5±8.5）% at various skeletal sites in females and （10. 9±4. 7）% in males. The most BMD loss was 32.5% and 18.9% in females and males respectively at radius＋ulna uhradistal end. The average BMD loss per 10 years at various skeletal regions was about 8.6% in the female elderly and 4.50% in the male elderly. Conclusions The study suggests that the ways of BMD loss present obvious gender difference at various skeletal regions in the elderly. The aging bone loss rate is higher in female than in male. Hip and forearm distal end are most sensitive sites, therefore, measuring these 2 skeletal sites may be helpful in the detection of low bone mass and osteoporosis in the elderly.