Evaluation of bone mass variation based on host-environment model

背景：大多数骨健康的流行病学研究仅限于分析骨量与社会经济或生活方式变量的关系，以及中年妇女和绝经后妇女的骨量。需要制定侧重于改善年轻妇女骨骼健康的公共卫生战略。方法：共纳入4595名年龄在12-22岁的女性。采用数字图像处理（DIP）和定量超声（OSI）方法测定骨矿物质含量（BMC）。通过健康问卷调查病史、运动习惯、饮食习惯等生活方式变量。在大学生中，78名女性描述了3天的饮食记录，并计算了能量和其他营养物质和矿物质的值。利用这些食物数据，通过因子分析生成营养素消费模式。采用以BMC值作为表达性状的路径模型，分析了遗传和环境因素对小学和初中兄弟姐妹BMC变异的影响。结果：在饮食模式分析中，导出了三个饮食因素；营养均衡，脂肪和蛋白质的模式。在控制了可能的混杂因素后，脂肪模式与低BMC值相关，表明成年早期骨质流失的风险增加。遗传因子和环境因子对BMC多样性的影响有限；总方差的14%和6%。结论：在年轻女性中，脂肪摄入与BMC呈负相关，而遗传贡献只占其多样性的一小部分。

Background : The most of the epidemiologic studies of bone health are limited to analyze relationship between bone mass and socioeconomic or lifestyle variables and for middle-aged women and those of after menopause. Public health strategies focused on improvement of bone health in young women are required.Methods : A total of 4,595 women aged 12-22 years was included in this study. Bone mineral content(BMC) was measured using DIP(digital image processing) and quantitative ultrasound methods(OSI). Lifestyle variables of medical history, habitual exercise, and food consumption were asked through health questionnaire. Among the college students, 78 women described 3-days food record and values of energy and other nutrients and minerals were calculated. Using of these food data, nutrient consumption patterns were generated with factor analysis. Genetic and environmental contributions to variation of BMC among the pair of brothers and sisters in elementary and junior high schools were analyzed using path models in which values of BMC was treated as expressed traits.Results : In dietary pattern analysis, three dietary factors were derived ; nutrient-balanced, fat, and protein patterns. After controlling probable confounding, fat pattern correlated with low value of BMC, indicating increased risk of bone loss in early adulthood. There was a limited contribution of both genetic and environmental factors on BMC diversity; 14% and 6% of total variance.Conclusion : In young women, fat intake is inversely associated with BMC, while genetic contribution accounted for small portion of its diversity.