北京6～19岁学生全身骨密度的研究

Study of whole-body bone mineral density measurement in 6 to 19 year-old students in Beijing

目的 了解 6～ 19岁男女学生全身骨密度 (BMD)的变化规律。方法 利用双能X线骨密度仪对 1139例健康男女学生行全身扫描 ,按性别不同 ,每 1岁分 1个组进行数据统计学分析。结果 6～ 10岁男女之间身高、体重、BMD、骨矿含量 (BMC)等方面差异无显著性意义。 6～ 14岁女孩和6～ 16男孩其身高、BMD和BMC年增长较明显 ,其后男女孩的身高、BMD和BMC年增长均不明显。在BMD的增长过程中有 2次突增期 :女孩出现在 11和 14岁时 ,男孩出现在 12和 15岁时。 12岁以前的女孩和 14岁以前的男孩其身高与全身总的BMD呈明显正相关 (P <0 0 1,r=0 40 2～ 0 814) ,之后男女孩的身高与全身总的BMD无相关性。男女孩的体重与BMD始终呈显著性正相关 (P <0 0 0 1,r =0 6 5 4～ 0 86 4)。结论 男女孩的身高和BMD生长发育各有特点和规律 ,其生长发育的重要时期为 ,女孩在 14岁以前 ,男孩在 16岁以前。

Objective To observe the changes of bone mineral density (BMD) in young boys and girls from 6-19 years old in Beijing area. Methods 1 139 healthy young boys and girls undergoing whole body scanning with dual energy X-ray bone densitometer were divided into different groups according to sex and age. Results There were no significant difference in body height, weight, BMD and bone mineral contents (BMC) between boys and girls from 6 to 10 years old. The annual growth rates of body height, BMD, and BMC were the fastest in girls from 6 to 14 and boys from 6 to 16 years old, respectively. Thereafter, the annual growth rates of body height, BMD, and BMC didn't significantly increase in boys and girls. There were two fast-growth periods in BMD growth stage, being at 11 and 14 years old in girls, and at 12 and 15 years old in boys. The total body BMD was significantly correlated with the height in girls under 12 years (P<0.001,r=0.485～0.575) and in boys under 14 years (P<0.01～0.001,r=0.402～0.814). Afterwards, no marked correlation was found between BMD and the height in various groups. Nevertheless, the body weight was always markedly correlated with BMD in boys and girls(P<0.001,r= 0.654～0.864). Conclusions The body height and BMD in young boys and girls had their own characteristics, and the important growth periods were under 14 years in girls and under 16 years in boys.