Fonseca A S, Szejnfeld V L, Terreri M T, Goldenberg J, Ferraz M B, Hilário M O
Departamento de Pediatria, Universidade Federal do Rio Grande do Norte, Natal, RN, Brasil.
Braz J Med Biol Res. 2001 Mar;34(3):347-52. doi: 10.1590/s0100-879x2001000300008.
The authors performed a study of bone mass in eutrophic Brazilian children and adolescents using dual-energy X-ray absorptiometry (DXA) in order to obtain curves for bone mineral content (BMC) and bone mineral density (BMD) by chronological age and correlate these values with weight and height. Healthy Caucasian children and adolescents, 120 boys and 135 girls, 6 to 14 years of age, residents of São Paulo, Brazil, were selected from the Pediatric Department outpatient clinic of Hospital São Paulo (Universidade Federal de São Paulo). BMC, BMD and the area of the vertebral body of the L2-L4 segment were obtained by DXA. BMC and BMD for the lumbar spine (L2-L4) presented a progressive increase between 6 and 14 years of age in both sexes, with a distribution that fitted an exponential curve. We identified an increase of mineral content in female patients older than 11 years which was maintained until 13 years of age, when a new decrease in the velocity of bone mineralization occurred. Male patients presented a period of accelerated bone mass gain after 11 years of age that was maintained until 14 years of age. At 14 years of age the mean BMD values for boys and girls were 0.984 and 1.017 g/cm2, respectively. A stepwise multiple regression analysis of paired variables showed that the "vertebral area-age" pair was the most significant in the determination of BMD values and the introduction of a third variable (weight or height) did not significantly increase the correlation coefficient.
作者使用双能X线吸收法（DXA）对营养良好的巴西儿童和青少年进行了一项骨量研究，以获取按实足年龄计算的骨矿物质含量（BMC）和骨矿物质密度（BMD）曲线，并将这些值与体重和身高相关联。从圣保罗医院（圣保罗联邦大学）儿科门诊诊所选取了120名男孩和135名女孩，年龄在6至14岁之间，居住在巴西圣保罗的健康白种儿童和青少年。通过DXA获得L2-L4节段椎体的BMC、BMD和面积。腰椎（L2-L4）的BMC和BMD在6至14岁之间两性均呈逐渐增加，其分布符合指数曲线。我们发现11岁以上女性患者的矿物质含量增加，这种增加一直持续到13岁，此时骨矿化速度出现新的下降。男性患者在11岁后出现一段骨量加速增加期，一直持续到14岁。14岁时，男孩和女孩的平均BMD值分别为0.984和1.017g/cm²。对配对变量进行的逐步多元回归分析表明，“椎体面积-年龄”配对在确定BMD值方面最为显著，引入第三个变量（体重或身高）并未显著提高相关系数。
