儿童户外活动及体质指数与维生素D营养状况的关系研究

Vitamin D status and its relationship to the time of outdoor activities and the body mass index in 0～6 years old children

目的了解江苏省0~6岁儿童维生素D(VitD)营养状况,探讨户外活动时间及体质指数与VitD水平的关系。方法采用分层随机整群抽样的方法,抽取江苏省12个地区0~6岁健康儿童5 289名,常规体检,测量体重、身长/高,计算体质指数(BMI),检测血清25-羟维生素D[25(OH)D]浓度,并进行相关问卷调查。结果 1)江苏省0~6岁儿童血清25(OH)D平均水平为(66.59±30.27)nmol/L,以25-(OH)D<75nmol/L作为VitD缺乏和不足的标准^([1]),VitD缺乏和不足者3 471例(65.6%);2岁以上儿童VitD水平[(61.65±27.57)nom/L]明显低于2岁以下婴幼儿[(70.25±32.55)nom/L]。2)在校正年龄、性别等影响因素后,多因素回归分析显示:户外活动时间、BMI与VitD水平相关,每日户外活动时间达4h以上者VitD水平最佳,随BMI增加,VitD水平呈上升趋势(F=4.168,P<0.05);以BMI>P 97th为肥胖标准,本研究中肥胖儿童409例(7.73%),肥胖儿童血清VitD水平[(65.94±29.56)nmol/L]低于正常儿童[(66.65±30.34)nmol/L],但差异无统计学意义(t=0.454,P=0.650)。结论江苏省儿童VitD营养状况处于相对缺乏状态,2周岁以上儿童VitD水平显著低于2岁以下儿童;足够的户外活动时间有利于维持较好的VitD营养状况;在未达到肥胖标准时,儿童BMI与VitD水平呈正相关。

Objective To evaluate the vitamin D （VitD） nutritional status,and to investigate the interaction of 25-hydroxy-vitamin D [25（OH）D] and outdoor activities time and the body mass index in 0-6 years old children. Methods U- tilizing a stratified random cluster sampling design,a total of 5 289 healthy children aged 0-6 years old were recruited from 12 regions of Jiangsu province. Anthropometric indices：weight,height,VitD levels were estimated by EI.ISA,and the related questionnaire investigation was carried. Results 1）The means and standard deviations of serum 25-（OH）D levels was （66.59± 30.27）nmol/L, 65.6% had VitD deficiency, VitD overdose and poisoning cases were not found. The level of 25 （OH）D was significantly higher in 0-2 years old group. 2）When children＇s age,gender and other variables were adjusted, outdoor activities time and the BMI were correlated with the serum 25-（OH）D levels （P〈0.01）, Daily time for outdoor ac- tivities up to 4 hours had best VitD level （F=11.45, P〈0.05）. The research objects receiving physical examination were screened by BMI（BMI〉P 97th was the standard for obesity）. In the study with 409 cases of obese children,the 25-（OH）D concentration increased with BMI （F = 4. 168, P〈 0. 05 ）. In addition, the serum 25-（OH）D levels in obesity and normal group were （65.94±29.56）nmol/L and （66.65± 30. 34） nmol/L,and this difference was not significant（t= 0. 454, P= 0. 650）. Conclusions There is a high prevalence of VitD deficiency in 0 to 6 year olds in Jiangsu province,especially for children over 2 years of age. The average VitD levels among children more exposed to sunlight is sufficient. When it is not up to the obesity standard, there is a positive correlation between 25-（OH）D levels and BMI.