中枢性性早熟女童身体质量指数与骨龄、胰岛素样生长因子1、血清25-羟维生素D的相关性分析

Correlation of body mass index with bone age,insulin-like growth factor 1,serum 25-hydroxyvitamin D in girls with central precocious puberty

目的探讨身体质量指数(BMI)对中枢性性早熟(CPP)女童的骨龄、胰岛素样生长因子1(IGF-1)、25-羟维生素D[25(OH)D]的影响。方法选取2016年1月至2018年12月因过早出现第二性征而至苏州大学附属张家港医院儿童内分泌专科就诊的158例女童为研究对象,中枢性性早熟组90例,其中肥胖组(n=20)、超重组(n=30)、正常体质量组(n=40);单纯性乳房早发育组68例,检测各组骨龄、IGF-1、25(OH)D,并将各指标水平与BMI进行Pearson相关分析。结果中枢性性早熟组骨龄(10.01±1.44)岁、IGF-1(328.73±143.57)μg/L均显著高于单纯性乳房早发育组(8.81±1.13)岁、(259.86±118.62)μg/L(P<0.05),中枢性性早熟组25(OH)D(23.16±4.86)μg/L显著低于单纯性乳房早发育组(25.86±5.84)μg/L(P<0.05)。中枢性性早熟女童25(OH)D超重组(23.197±3.558)μg/L和肥胖组(16.395±3.254)μg/L均显著低于正常体质量组(26.505±5.377)μg/L(P<0.05),且肥胖组25(OH)D也低于超重组(P<0.05);骨龄、IGF-1在中枢性性早熟女童肥胖组、超重组、正常体质量组三组间差异无统计学意义(P>0.05)。中枢性性早熟女童BMI与骨龄呈正相关(r=0.23,P=0.031),BMI与IGF-1水平亦呈正相关(r=0.35,P=0.001),同时BMI与25(OH)D水平呈负相关(r=−0.71,P<0.001)。结论中枢性性早熟女童IGF-1、骨龄明显高于单纯性乳房早发育组,血清IGF-1水平及骨龄提前或可以作为青春期启动的信号,但性腺轴一旦启动,IGF-1、骨龄受BMI的影响并不显著。中枢性性早熟女童BMI与25(OH)D水平呈显著负相关,故在性早熟儿童特别是肥胖儿童的治疗中需重视25(OH)D水平的监测及补充。

Objective To explore the effects of body mass index(BMI)on bone age,insulin-like growth factor 1(IGF-1)and 25-hydroxyvitamin D[25(OH)D]in girls with central precocious puberty.Methods Totally 158 girls with secondary sexual characteristics,who were treated in Department of Pediatric Endocrinology of Zhangjiagang Hospital Affiliated to Soochow University from January 2016 to December 2018,were selected as the research objects.There were 90 cases in central precocious puberty group,including obesity subgroup(n=20),overweight subgroup(n=30),normal BMI subgroup(n=40),and 68 cases in simple premature breast development group.Bone age,IGF-1,25(OH)D were detected in each group,and Pearson correlation analysis was conducted between the levels of all indexes and BMI.Results Bone age and IGF-1 level in the central precocious puberty group were significantly higher than in the simple breast development group[(10.01±1.44)years old vs.(8.81±1.13)years old,(328.73±143.57)μg/L vs.(259.86±118.62)μg/L;P<0.05],while 25(OH)D level in the central precocious puberty group was significantly lower than that in the simple breast development group[(23.16±4.86)μg/L vs.(25.86±5.84)μg/L,P<0.05].25(OH)D level in the overweight subgroup and the obesity subgroup were significantly lower than that in the normal BMI subgroup[(23.197±3.558)μg/L,(16.395±3.254)μg/L vs.(26.505±5.377)μg/L,P<0.05],and 25(OH)D level in the obesity subgroup was significantly lower than that in the overweight subgroup(P<0.05).There were no statistically significant differences in bone age and IGF-1 among obesity,overweight and normal BMI subgroups(P>0.05).BMI of central precocious puberty girls was positively correlated with bone age(r=0.23,P=0.031)and IGF-1 level(r=0.35,P=0.001),and negatively correlated with peak values of 25(OH)D(r=−0.71,P<0.001).Conclusions IGF-1 and bone age of girls with central precocious puberty were significantly higher than those of girls with simple premature breast development.Serum IGF-1 level and bone age may serve as a signal of initiation of puberty,but once the gonad axis is activated,IGF-1 and bone age are not significantly affected by BMI.BMI of girls with central precocious puberty was significantly negatively correlated with 25(OH)D level,so the monitoring and supplement of 25(OH)D level should be emphasized in the treatment of children with precocious puberty,especially obese children.