钙强化奶粉干预对北京某郊区12～15 岁青少年体格和骨量的影响研究

发布时间：2018-09-03 16:57

【摘要】：目的观察补充强化钙奶粉对北京郊区青少年体格生长、体成分及骨骼发育的影响，为改善北京郊区青少年营养状况提供科学依据。方法本研究为随机对照干预研究。选取北京市怀柔区3个乡镇，每个乡镇各随机选取1所初中初一的健康学生，共286名作为研究对象。研究对象在测定基线骨量指标后，以基线骨量为随机指标，在各组基线骨量没有显著性差异的基础上，按照班级为单位随机分为1个对照组和3个补充组。对照组学生保持日常饮食，没有干预措施；补充组内学生按照个体随机分为a组（每天补充含钙300mg和维生素D10μg的奶粉40g）、b组（每天补充含钙600mg和维生素D10μg的奶粉40g）和c组（每天补充含钙900mg和维生素D10μg的奶粉40g）。要求家长每天早上和晚上分两次为学生准备，研究对象在家长监督下服用。对干预组学生进行为期1.5年的钙强化奶粉补充。通过问卷调查收集研究对象的一般情况、家庭环境状况、膳食摄入情况及身体活动情况，并检查其生长发育状况。采用双能X线吸收仪(Dual Energy X-rayAbsorptiometry，DEXA)测量学生全身、腰椎、股骨颈、全股骨及Wards区的骨矿物含量（Bone Mineral Content，BMC）、骨矿物密度(Bone Mineral Density，BMD)及骨面积（Bone Area，BA），同时测定全身体成分。所有测量分别在干预前、干预1年时及干预1.5年时各测量一次。采用混合线性模型分析干预效果。结果（1）共调查初中生286人，平均年龄13.1±0.6岁。（2）干预前，四组间年龄、身高、体重、BMI、全身BMC、全身BMD和BA及体力活动均无统计学差异（P0.05）；每天总能量摄入、碳水化合物摄入量、铁、维生素E、青春发育分期略有差异（P0.05）；（3）干预后，男、女生身高各组间差异均无显著性，中期和末期身高的增量男、女各组间差异同样无统计学意义。调整混杂因素后，男生身高干预效应有统计学意义（P=0.0359），但女生身高干预效应无统计学意义。调整混杂因素后，男生体重有干预效应但无统计学意义（P=0.0621）；女生体重干预效应无统计学意义。男、女BMI中期及末期增量各组间差异无统计学意义。调整混杂因素后，男生BMI无显著性组间效应而女生BMI组间效应有统计学意义（P=0.045）；男生BMI有干预效应但无统计学意义（P=0.1536），女生BMI干预效应无统计学意义。男、女生瘦体重、体脂和体脂百分比四组间差异均无统计学意义（P0.05）；干预中期及末期三指标均有所增加，但组间均无统计学差异。调整混杂因素后，男生瘦体重、体脂及体脂百分比组间效应、时间效应及干预效应无统计学意义；女生瘦体重、体脂和体脂百分比时间效应均有统计学意义（P0.05），瘦体重干预组学生增加有高于对照组趋势，但无统计学意义（P=0.1081），体脂及体脂百分比干预效应均无统计学意义。(4)调整可能混杂因素后，男生全身骨量时间效应有统计学意义（P0.05），干预效应无统计学意义（P=0.0916）；女生中期全身骨量a组及b组分别增加241.0g和213.1g较对照组学生176.3g高36.7%和20.9%，c组学生增加171.5g，较对照组学生低2.7%（P=0.0422）；末期全身骨量a组及b组学生分别增加327.7g和308.7g较对照组学生251g高30.6%和23.0%，c组学生增加244.4g较对照组学生低2.7%（P=0.0692）。调整可能混杂因素后，，女生全身骨量时间效应有统计学意义（P0.0001），但干预效应无统计学意义（P=0.1919）；（5）男生全身骨密度中期增量a组、b组及c组分别为0.042g/cm2、0.037g/cm2和0.049g/cm2较对照组的0.033g/cm2高27.3%、12.1%和48.5%（P0.05）；调整混杂因素后，男生中期全身BMD较基线a组和c组分别增加0.047g/cm2和0.051g/cm2，较对照组学生的0.038g/cm2分别高23.7%和34.2%，b组学生增量与对照组相等；末期全身骨密度较基线a组和b组学生分别增加0.078g/cm2和0.071g/cm2，较对照组学生0.081g/cm2分别低3.7%和12.3%，c组学生为0.081g/cm2与对照组学生相等。调整混杂因素后全身骨密度干预效应有统计学意义（P=0.0187）。（6）女生全身骨密度中期增量a组和b组分别为0.050g/cm2和0.042g/cm2，较对照组学生的0.033g/cm2高51.5%和27.3%，c组为0.029g/cm2较对照组学生低12.1%（P=0.0625）；全身骨密度末期增量a组和b组学生分别为0.082g/cm2和0.069g/cm2，较对照组学生的0.054g/cm2高51.9%和27.8%，c组为0.051g/cm2较对照组学生低5.6%（P=0.0074）；调整混杂因素后，女生中期全身BMD较基线a组和b组分别增加0.050g/cm2和0.041g/cm2，较对照组学生的0.33g/cm2分别高51.5%和24.2%，而c组为0.029g/cm2较对照组学生低12.1%；女生末期全身BMD较基线a组、b组和c组分别增加0.081g/cm2、0.068g/cm2及0.057g/cm2，较对照组学生0.054g/cm2分别高50%、25.9%及5.6%；调整混杂因素后，全身骨密度干预效应有统计学意义（P=0.0307）。(7)调整混杂因素后，男、女生BAP及TRAP-5b和男生IGF-1、女生PTH均时间效应有统计学意义（P0.05）；男、女生各生化指标均无组间效应，男生IGF-1（P=0.0125）和PTH（P=0.0348）干预效应有统计学意义，女生各生化指标均干预效应无统计学意义。结论北京郊区青少年平均每日钙摄入水平较低，通过1.5年补充钙强化奶粉能促进男、女生骨量、骨密度增长，并对其营养状况有一定改善作用，但对男、女生身高和体重影响不显著；青少年应保持适当体力活动，增加钙摄入以满足体格生长发育需要。
[Abstract]:Objective To observe the effects of supplementation of fortified calcium milk powder on physical growth, body composition and bone development of adolescents in Beijing suburbs, and to provide scientific basis for improving nutritional status of adolescents in Beijing suburbs.
Methods A randomized controlled intervention study was conducted in three townships in Huairou District of Beijing. A total of 286 healthy junior middle school students were randomly selected from each of the townships. The students in the supplementary group were randomly divided into group a (supplemented with milk powder containing 300 mg calcium and 10 mg vitamin D daily) and group B (supplemented with milk powder containing 600 mg calcium and 10 mg vitamin D daily) and group C (supplemented with milk powder containing 40 g vitamin D daily). Calcium 900MG and vitamin D 10 mg of milk powder 40g. Parents were asked to prepare for the students twice a day in the morning and evening. The subjects were given calcium supplementation under the supervision of their parents. The students in the intervention group were given calcium supplementation for 1.5 years. Bone Mineral Content (BMC), bone mineral density (BMD) and bone area (BA) in the whole body, lumbar spine, femoral neck, femur and Wards region were measured by dual energy X-ray absorptiometry (DEXA). All measurements were taken before intervention, 1 year after intervention and 1.5 years after intervention respectively. Mixed linear model was used to analyze the effect of intervention.
Results (1) A total of 286 junior middle school students were investigated, with an average age of 13.1 (+ 0.6 years). (2) Before the intervention, there were no significant differences in age, height, weight, BMI, BMC, BMD, BA and physical activity among the four groups (P 0.05); daily total energy intake, carbohydrate intake, iron, vitamin E, and puberty stages (P 0.05); and (3) After the intervention, there were slight differences in male and female. There was no significant difference in height among different groups, and there was no significant difference in height increment between male and female at the middle and final stages. There was no significant difference in BMI increment between male and female. After adjusting the confounding factors, there was no significant inter-group effect in BMI of male students and significant inter-group effect in BMI of female students (P = 0.045); there was no significant intervention effect in BMI of male students but no significant difference in BMI of female students (P = 0.1536). There was no significant difference in BMI intervention effect between male and female students. There was no significant difference in lean weight, body fat and body fat percentage among the four groups (P There was no significant difference in the pre-effect; there was significant difference in lean weight, body fat and percentage of body fat between girls (P 0.05). The increase of lean weight intervention group was higher than that of the control group, but there was no significant difference (P = 0.1081). There was no significant difference in the intervention effect of body fat and percentage of body fat between the two groups. (4) After adjusting the possible confounding factors, there was no significant difference in body fat and percentage of body fat among boys. Bone mass time effect was statistically significant (P 0.05), intervention effect was not statistically significant (P = 0.0916); girls in the mid-term total body bone mass group A and group B increased 241.0 g and 213.1 g respectively higher than the control group students 176.3 g 36.7% and 20.9%, group C students increased 171.5 g, lower than the control group students 2.7% (P = 0.0422); end-stage total body bone mass group A and group B students increased 3.7% respectively. 27.7g and 308.7g were 30.6% and 23.0% higher than 251g in control group, and 244.4g in group C was 2.7% lower than that in control group (P = 0.0692). After adjusting the possible confounding factors, the time effect of whole body bone mass of female students was statistically significant (P 0.0001), but the intervention effect was not statistically significant (P = 0.1919); (5) the mid-term increment of bone mineral density of male students in group a, group B and group C 0.042g/cm2, 0.037g/cm2 and 0.049g/cm2 were 27.3%, 12.1% and 48.5% higher than those of the control group (P 0.05), respectively. After adjusting the confounding factors, the BMD of the boys in the middle period increased by 0.047g/cm2 and 0.051g/cm2 respectively, 23.7% and 34.2% higher than those of the control group, and the increment of the students in group B was the same as that of the control group. Bone mineral density increased by 0.078 g/cm 2 and 0.071 g/cm 2 respectively compared with baseline group A and group b, which were 3.7% and 12.3% lower than that of control group 0.081 g/cm 2, respectively, and 0.081 g/cm 2 was equal to that of control group C. The intervention effect of whole body bone mineral density after adjusting the confounding factors was statistically significant (P = 0.0187). (6) Medium-term increment of whole body bone mineral density of female students in group A and group B was significantly lower than that of control group.081 g/cm 2, respectively. 0.050g/cm2 and 0.042g/cm2, 51.5% and 27.3% higher than that of the control group, 0.029g/cm2 lower than that of the control group by 12.1% (P = 0.0625), total body bone mineral density (BMD) increment of 0.082g/cm2 and 0.069g/cm2 in group A and group b, 51.9% and 27.8% higher than that of the control group by 0.054g/cm2, and 0.051g/cm2 lower than that of the control group by 5.6% (P = 0.0625). After adjusting the confounding factors, the BMD of girls in the middle period increased by 0.050 g/cm 2 and 0.041 g/cm 2 respectively, 51.5% and 24.2% higher than that of the control group, while that of the C group was 0.029 g/cm 2 was 12.1% lower than that of the control group. 7 g/cm2, 50%, 25.9% and 5.6% higher than that of the control group, respectively. After adjusting the confounding factors, the intervention effect of BMD was statistically significant (P = 0.0307). (7) After adjusting the confounding factors, BAP, TRAP-5b and IGF-1 of male, female and PTH of female students were statistically significant (P 0.05); there was no intergroup effect between male and female biochemical indexes. The intervention effects of IGF-1 (P = 0.0125) and P TH (P = 0.0348) in boys were statistically significant, while the intervention effects of biochemical indexes in girls were not statistically significant.
Conclusion The average daily calcium intake level of adolescents in Beijing suburbs is low. Supplementary calcium fortified milk powder for 1.5 years can increase bone mass and bone mineral density of male and female students, and improve their nutritional status to some extent, but has no significant effect on the height and weight of male and female students. Long development needs.
【学位授予单位】：安徽医科大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R151.4

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