小于胎龄儿青春前期女孩硫化脱氢表雄酮和胰岛素水平的研究

目的探讨小于胎龄儿(SGA)青春前期女孩肾上腺机能初现及是否具有肾上腺机能早现、高肾上腺雄激素血症、高胰岛素血症和胰岛素抵抗现象。方法以符合纳入标准的SGA 39例为研究对象,年龄(7.4±1.7)岁,42例适于胎龄儿(AGA)为对照组,年龄(7.4±1.7)岁。在隔夜空腹12 h后,行身体检查,并抽血检测空腹血糖、胰岛素、硫化脱氢表雄酮(DHEAS)、皮质醇和雌二醇。胰岛素敏感性用空腹血糖与胰岛素乘积的倒数再取自然对数来评价。结果两组中未发现肾上腺机能早现的临床表现,两组间孕母孕龄、年龄、体重指数、空腹血糖、皮质醇、雌二醇和胰岛素敏感性指数差异无统计学意义。SGA组出生体重、研究时的身高和体重均低于AGA组,SGA血清胰岛素和DHEAS水平均高于AGA组(对数转换值:1.076±0.041vs.1.050±0.051,P<0.05;2.637±0.271vs.2.514±0.250,P<0.05)。AGA组DHEAS值在7岁以后出现明显增加,SGA组DHEAS值出现增加的趋势与AGA组比较有所提前。结论AGA女孩肾上腺机能初现的年龄约为7岁,而SGA女孩肾上腺机能初现有始动提前的趋势,青春前期SGA女孩有高肾上腺雄激素血症和胰岛素水平升高的现象,但以胰岛素敏感性指数来评价,尚未发现胰岛素抵抗现象。

Dehydroepiandrosterone sulfate and insulin of prepubertal girls born small for gestational age

OBJECTIVES: To investigate whether the association between low birth weight and increased risk of developing premature adrenarche, adrenal hyperandrogenism, hyperinsulinism and insulin resistance is apparent in prepubertal girls born small for gestational age (SGA) and analyze when adrenarche occurs in SGA infants and normal birth weight girls. METHODS: The study was performed in 39 prepubertal SGA girls with a mean age of 7.4 +/- 1.7 years and 42 prepubertal appropriate for gestational age (AGA) girls with a mean age of 7.4 +/- 1.7 years served as controls. All children were born at term and were prepubertal. Detailed physical examination was performed for all the children after 12 h of overnight fasting. Blood samples were taken for the measurement of fasting glucose (FPG), insulin (FIns), dehydroepiandrosterone sulfate (DHEAS), cortisol and estradiol concentrations. Insulin sensitivity was assessed by insulin sensitivity index IAI = log(e) (FPG x FIns)]. RESULT: There was no premature adrenarche in SGA and AGA groups. Birth weight was significantly lower in SGA group (P < 0.001). Gestational age was similar in both groups. At the time of the study, the ages, body mass index (BMI), fasting glucose, cortisol and estradiol did not significantly differ between the two groups. But body height and weight were significantly lower in the SGA group (P < 0.05 for both). The fasting plasma insulin in the SGA group was higher than that in AGA group (common logarithmic transformation: 1.076 +/- 0.041 vs. 1.050 +/- 0.051, P < 0.05). The insulin sensitivity index was not significantly different between the two groups (-4.0165 +/- 0.1761 vs. -3.9768 +/- 0.2314). The serum DHEAS was significantly higher in SGA children than in AGA children (common logarithmic transformation: 2.637 +/- 0.271 vs. 2.514 +/- 0.250, P < 0.05). From about age 7 the concentration of DHEAS had a gradual rise in AGA children. The time of DHEAS rise tended to be earlier in SGA children compared with AGA children. CONCLUSIONS: Adrenarche commences at approximately 7 years of age in AGA girls. The time of adrenarche tended to be earlier in SGA girls compared with AGA girls. There were adrenal hyperandrogenism and hyperinsulinism in prepubertal girls born small for gestational age. But there was no insulin resistance as assessed by insulin sensitivity index.