A Survey Of Bone Mass Density And Its Correlates Of Chinese Youth

Objective:The purpose study is to learn the state of bone mineral density in children andadolescence,and to evaluate the influence in bone mineral density,and analysis ofits characteristics,for example:BMI,puberty,sleep duration,carbonated soft drinkconsumption,physical activity and ect.To ascertain those benefit for children andadolescence’s bone mineral density and optimal peak bone mass.Methods:This study adopts the method of convenience sampling.The study recruited volunteersfrom fourth grade to Junior Three in Xi’an and Tianjin,choose six hundred volunteers inwho was participated in voluntary.BMD was measured by Metriscan(The United StatesAlara company),their second/third/fourth finger in non-dominant hand were measured,thethird finger’s BMD was used in statistics in the end.Then,the weight and height weremeasured. Selects the international commonly used acceleroeter GT3X+for the objectivemeasurement of physical activity,after measured, the raw data were downloaded byActiLife6.5.2. After objective measurements,the researchers asked and recorded thequestion about puberty/sleep duration/carbonated soft drink consumption/breakfast/milk.Descriptive statistics is used to calculate all the mean and standard deviation of the index;The influence factors of affect the growth of bone mineral density using Multiple LinearRegression,such as: puberty/BMI/breakfast/milk and VPA. Analysis of covariance used insingle factor in under the influence of other factors, the influence of different levels onbone mineral density in same group. Bonferroni （B） post hoc is used for multiplecomparison after the variance analysis, P<0.05there are significant differences.Results:This study tests600students from the four grade to the junior three, except the notconform to the requirements data analysis of271people,329effective test data and aged10to15. Including172men, average age was13.26±1.47years old;female,157people,average age12.59±1.20years old. Female bone mineral density at the age of tenyears(0.24±0.02g/cm2VS0.22±0.02g/cm2, P<0.05),12years old(0.27±0.02g/cm2VS0.25±0.02g/cm2, P<0.05),13years old (0.28±0.02g/cm2VS0.27±0.02g/cm2, P<0.05),14years old(0.30±0.02g/cm2VS0.28±0.03g/cm2, P<0.05) were significantly higher thanboys, P<0.05. The boy mid pubertal (0.28±0.03g/cm2VS0.25±0.02g/cm2, P<0.05), LatePuberty bone mineral density (0.31±0.03g/cm2VS0.29±0.02g/cm2, P<0.05) were higher than the girls.Through multiple linear regression analysis: Effect on bone mineral densityfrom large to small is: puberty(β=0.51,P<0.05)/BMI(β=0.15,P<0.05)/milk(β=0.13，P<0.05)/VPA(β=0.12,P<0.05)/sleep(β=-0.13,P<0.05). The covariance analysis foundthat: puberty effects on bone mineral density have significantly main effect, bone mineraldensity of overall sample(F（4，329）=43.73，P<0.05), bone mineral density of men(F（4,171）=30.06,P<0.05), bone mineral density of female（F（4,156）=28.30,P<0.05; The influence ofhigh intensity of physical activity on bone mineral density: bone mineral density of overallsample(F（2,329）=6.99,P<0.05)、bone mineral density of men(F（2,172）=7.23,P<0.05);Sleepduration effects on bone mineral density: bone mineral density of overall sample(F（6,329）=2.76,P<0.05)bone mineral density of men(F（6,172）=2.30,P<0.05).Conclusion:The bone mineral density of children and adolescents with age growth.The importantinfluence factors of bone mineral density of the children and adolescentsare:puberty/BMI/drinking milk/high intensity of physical activity/sleep duration.