儿童血清维生素D水平与身体成分及超声骨密度的相关性

Correlation of serum vitamin D level with body composition and ultrasonic bone mineral density in children

目的探讨儿童血清维生素D水平与身体成分和骨密度的相关性。方法采用单纯随机抽样法抽取2020年1月至2021年12月于宜宾市翠屏区妇幼保健院进行儿童保健的6~12岁儿童559例,采用化学发光法测定血清25-羟维生素D(25-hydroxyvitamin D,25OHD),生物电阻抗法测定身体成分,超声测定右侧跟骨骨密度,分析血清25OHD水平和体成分指标及超声骨密度的相关性。结果559例儿童血清25OHD水平为(95.0±26.5)nmol/L,维生素D不足和缺乏率分别为18.4%和5.0%,体型超重或肥胖者维生素D缺乏率高于消瘦或正常者(P<0.05)。骨骼肌质量、骨骼肌质量指数(skeletal muscle mass index,SMI)、蛋白质和无机盐含量分别为(10.85±2.07)kg、(5.83±0.77)kg/m^(2)、(5.48±0.60)kg和(1.19±0.11)kg,男童高于女童,年龄越大含量越高,正常和超重肥胖者高于消瘦者(P<0.001)。宽带超声衰减(broadband ultrasonic attenuation,BUA)值为(98.2±11.6)dB/MHz,骨强度指数(stiffness index,SI)为(87.1±7.2),仅不同年龄段的BUA和SI差异有统计学意义(P<0.01)。相关性和关联性分析显示,血清25OHD与骨骼肌质量、SMI、蛋白质含量、无机盐含量、BUA和SI均呈正相关,相关系数r分别为0.508、0.476、0.392、0.401、0.597和0.561(P<0.05),χ^(2)检验的列联系数分别为0.111、0.166、0.123、0.164、0.096和0.115(P<0.05)。结论儿童维生素D缺乏较普遍,维生素D营养状况与体成分和骨密度呈正相关,应增加户外活动和合理补充维生素D制剂。

Objective To explore the correlation between serum vitamin D level and body composition and bone mineral density in children.Methods Between January 2020 and December 2021,559 children aged 6-12 years were selected from Maternal and Child Health Hospital of Cuiping in Yibin by simple random sampling method.Serum 25-hydroxyvitamin D(25OHD)was measured by chemiluminescence assay,body composition was measured by bioelectrical impedance method,bone mineral density of right calcaneus was measured by ultrasound,and the correlation between serum 25OHD level,body composition index,and ultrasonic bone mineral density was analyzed.Results The serum 25OHD level of 559 children was(95.0±26.5)nmol/L with the prevalence of vitamin D deficiency of 18.4%.The prevalence of vitamin D deficiency in overweight or obese group was higher than that in lean or normal groups(P<0.05).The skeletal muscle mass,skeletal muscle mass index(SMI),protein,and inorganic salt were(10.85±2.07)kg,(5.83±0.77)kg/m^(2),(5.48±0.60)kg,and(1.19±0.11)kg,respectively.The broadband ultrasonic attenuation(BUA)value was(98.2±11.6)dB/MHz and the stiffness index(SI)was(87.1±7.2).Only the differences of BUA and SI among different age groups were statistically significant(P<0.01).Correlation analysis showed that serum 25OHD level was positively correlated with skeletal muscle mass,SMI,protein content,inorganic salt content,BUA,and SI,with the correlation coefficient of 0.508,0.476,0.392,0.401,0.597,and 0.561,respectively(P<0.05)and the contingency coefficient was 0.111,0.166,0.123,0.164,0.096,and 0.115,respectively(P<0.05).Conclusions Vitamin D deficiency is common in children.Vitamin D status is associated with body composition and bone mineral density.Outdoor activities need to be increased and vitamin D should be adequately supplemented.