四川省阿坝州藏羌和汉族儿童少年骨量影响因素分析

Influencing Factors on Bone Mass Among Adolescents of Tibetan, Qiang and Han Adolescents Living In A-ba County in Sichuan Province

目的了解四川省阿坝州藏、羌、汉族儿童少年骨量的影响因素,为制定学生营养政策、预防骨质疏松提供基础资料和科学依据。方法采用问卷调查方式,收集四川省阿坝藏羌自治州1821名7～18岁藏、汉、羌族男、女生的膳食营养素摄入和体力活动情况,测量身高和体重;采用生物电阻抗仪测定体成分,并用双能X线吸收仪(DEXA)测定前臂近端1/3处和远端1/10处骨矿物含量(BMC)和骨面积(BA)。结果多元线性回归分析发现,瘦体重对前臂远端1/10处和前臂近端1/3处的BMD和BMC的变异贡献要高于其他因素,其标准偏回归系数分别为0.567,0.687,0.346和0.482;藏族、钙摄入量、体力活动能量消耗等因素对前臂远端1/10处BMD和BMC的作用有统计学意义,其标准化回归系数分别为0.094和0.061,0.034和0.022,0.034和0.024。结论体重(尤其是瘦体重)是儿童少年骨量的主要影响因素,民族、膳食营养素摄入、体力活动因素也是影响儿童少年骨量的重要因素。

Objective To study the influencing factors on bone mass growth o Tibetan, Qiang and Han nationality adolescents in puberty, and to provide scientific evidence for student＇s nutritional strategy and the prevention of osteoporosis. Methods Total of 1 821 healthy volunteer students was recruited in Mao County and Heishui County of Sichuan Province （aged 7 - 18, 897 boys and 924 girls）. Dietary intake and physical activity information were collected through questionnaires. Their height and weight were examined. Body compositions were examined by the bioelectrical impedance analysis. Bone mass of non-dominant forearm were measured by dual energy X- ray absorptiometry （DEXA）. Results Stepwise multiple regression analysis showed that the dominant factor of the proximal forearm BMD and BMC in boys and girls was lean body mass（ B = 0.567, 0.678, 0. 346, 0.482, P 〈 0.01 ）. Tibetan was significantly positively correlated with the proximal forearm BMD and BMC in boys and girls （ B = 0.094, 0.061, P 〈 0.01 ）. Dietary calcium was one of the important influencing factors of the distal forearm BMD and BMC in boys and girls（ B = 0.034, 0.022, P 〈 0.01 ）. The total energy consumption of physical activity were also significantly correlated with distal forearm＇s BMD and BMC（B=0.034,0.024, P〈0.01）. Conclusion Weight especially lean body mass is the major determinant to bone mass in boys and girls. Nationality, nutrition intake and physical activity are also the important determinant of bone mass.