【作者】 廖文君；

【导师】 赵琳；

【作者基本信息】 昆明医学院 ， 儿科学， 2007， 硕士

【摘要】 骨质疏松症(osteoporosis，OP)已成为世界各国日益关注的公共卫生问题。骨质疏松症是以骨量减少，骨微结构的破坏为特征的全身性骨骼系统退化性病变。骨量减少，骨脆性增加易发生骨折。临床上以骨密度和骨矿含量减少作为诊断骨质疏松症的依据。根据我国第五次人口普查资料预测，我国的原发性骨质疏松症患者约为8800万人，其中男女比例为1：6。近几十年来虽然对骨质疏松症开展了大量研究，但迄今为止仍缺乏有效的方法来大幅改善骨密度，进而治疗骨质疏松症。因此，早期预防成为防治该病最经济有效的措施和必需实施的手段。预防骨质疏松症的根本措施之一，是提高成年早期骨量的累积和骨峰值。围青春期是人类生命过程中生长发育的第二高峰期，也是影响骨峰值获得、早期预防骨质疏松症的关键时期。因此，在围青春期，在个体遗传背景许可的范围内获得最大骨峰值成为预防骨质疏松症首要的措施和手段。人体骨量受多种因素影响，概括起来包括遗传因素和环境因素。大多数学者认为影响骨质疏松症的遗传因素约占80％，环境因素约占20％。尽管如此，环境因素仍然是值得研究的重要课题，这是因为包括膳食钙摄入量、体力活动等在内的环境因素对骨量和骨密度的影响不仅是易于确认的因素，更是可以改变、控制和干预的因素。影响骨密度的环境因素很多，主要包括膳食营养状况、体力活动状况等。哪种因素影响更大?如何影响?都是值得研究，需要阐明的课题。因此，观察此期青少年骨量和骨密度的变化规律，研究影响此期骨量和骨密度的相关因素，阐明其对骨量和骨密度的贡献大小，均具有理论和实际的双重意义。国内以儿童及青少年作为对象的研究极少，而中西方儿童及青少年在膳食构成、活动方式等方面存在着巨大差异，国外的研究结果可能不适合我国的实际情况。因此，本课题调查研究了青春期青少年钙营养、体力活动及体格发育状况，同时测定了全身多部位骨密度，分析了上述各种因素与骨密度及骨量的关系，为提高遗传条件下青少年的骨密度，发挥其生长发育的潜能，为骨质疏松症的早期预防奠定理论基础。[目的]：本研究对昆明市青少年进行骨密度测定，并对骨密度的影响因素进行问卷调查，以了解昆明地区青少年骨量水平及影响因素。[方法]：利用双能X线骨密度测定仪测量昆明市某中学55名12—14岁青少年腰椎及髋部的骨密度，然后通过问卷调查法和直接访谈法的形式，对其生活方式、饮食习惯和运动情况等进行调查。实验结果采用SPSS 11.5统计软件进行分析。[结果]：(1)女生腰椎、左右双侧股骨颈、大转子的骨密度明显高于男生；(2)每日坚持喝牛奶的学生腰椎及左右双侧髋部的骨密度显著高于不喝牛奶的学生：(3)运动的学生腰椎及左右双侧髋部的骨密度与不运动者有显著差异；(4)月经初潮年龄早的女生骨密度较高(P＜0.05)；(5)体重与BMD相关，体重越重BMD越高，但身高与BMD无明显相关关系；(6)体重、摄入牛奶及运动与否与骨密度的相关性顺序为牛奶的摄入＞体重＞运动，即牛奶的摄入对骨密度的影响最大，运动对骨密度的影响最小。[结论]：影响昆明市青少年骨量水平的重要因素是：牛奶的摄入、运动、性别和体重，因此多喝牛奶，多做户外运动是目前提高骨密度，预防成年后骨质疏松发生的有效方法。更多还原

【Abstract】 Osteoporosis is an increasingly popular public health problem in the world, characterized by low bone mineral density and the deterioration of skeletal micro architecture, which leads to an increased risk of fracture. Bone mineral density (BMD) and bone mineral content (BMC) are widely used as direct indicators of bone mass. It is estimated that there are 88 million osteoporotic individuals in China. The ratio of number of osteoporotic men and women is 1:6. For the past decades, a large number of studies have been focused on osteoporosis. However, up to now, no efficient measure is available to substantially improve BMD and treat osteoporosis. Therefore, early prevention is the most economical method to prevent this disease. One of the primary prevention measures is to maximize peak bone mass (PBM) within genetic potential in and before early adulthood. Puberty is a critical stage of bone development, in which a large proportion of bone mass is accumulated. Therefore, maximizing bone accumulation during puberty will be beneficial to maximize the PBM. Although, environmental factors may contribute a much less proportion of the differences in bone mass among individuals than genetic factors, it is valuable to pay more attention to environmental factors since only they can be modified. Among the environmental factors, dietary factors and physical activity play a key role in the prevention of osteoporosis. So it should be theoretically and practically helpful to observe the development principles of bone mass in children and to investigate its predictors and define their corresponding contributions to bone mass. In this study, we assessed the major determinants of bone mass in children, and evaluate the association of bone mass with dietary calcium and physical activities after adjusting for other potential confounders. The results may provide scientific evidence for promoting healthy nutrition and life-style in children to fulfil their growth potential and early prevent the development of osteoporosis.[Objective]: In order to investigate the level of adolescent bone mass and the correlated influence factors in Kunming, Yunnan province ,this research has carried on the bone mineral density to test the adolescent and has carried on questionnaire investigation to influential factors.[Method]: bone mineral density (BMD) of lumbar and proximal femur of 55 adolescent, aged 12 to 14, was measured with Dual energy X-ray absorptiometry (DEXA) in middle school, Kunming city. Then the Survey of its life style, eating habit and movement situation has been taken by means of questionnaire investigation and direct interview.[Result]: ( 1 ) the level of BMD of lumbar and femur neck and femur GT in girls are significant higher than the ones in boys. ( 2 ) The BMD of adolescent who drink milk every day were greater than that of adolescent without milk intake in lumbar and proximal femur. ( 3 ) Compared with juvenile who do not like outdoor exercise, those like outdoor exercise revealed higher BMD levels in lumbar and proximal femur. ( 4 ) Menarche at earlier age was associated with a higher BMD (P<0.05). ( 5 ) There is a positively correlation between BMD and weight, but BMD is not correlated with height. ( 6 ) The correlation concerned about bone mineral density with milk intake , weight, outdoor exercise: milk intake > weight > outdoor exercise. That is to say, milk intake has the strongest influence on bone mass, while outdoor exercise has the weakest one.[Conclusion]: The correlated influence factors of BMD in adolescent, Kunming city were respective: milk intake, outdoor exercise, sex and weight. So it is the effective way that more milk intake and outdoor exercise in enhancing bone mineral density, preventing the occurrence of osteoporosis.更多还原