The Center for Research in Reproduction, University of Virginia Health System, Charlottesville, Virginia, USA.
Obesity (Silver Spring). 2010 Nov;18(11):2118-24. doi: 10.1038/oby.2010.58. Epub 2010 Mar 25.
Obesity in peripubertal girls is associated with hyperandrogenemia (HA), which can represent a forerunner of polycystic ovary syndrome (PCOS). However, not all obese girls demonstrate HA, and determinants of HA in obese girls remain unclear. We hypothesized that insulin and luteinizing hormone (LH) are independent predictors of free testosterone (T) concentration in obese girls. To assess this further, fasting morning blood samples were collected from 92 obese (BMI-for-age percentile ≥95) girls in various stages of puberty. A multivariate regression model was then constructed using free T (dependent variable), LH, insulin, pubertal group (early, mid-, or late puberty), BMI z-score, and age. Free testosterone (T) concentrations were highly variable among obese girls in each pubertal group. The regression model accounted for roughly half of the variability of free T in obese girls (adjusted R(2) = 0.53, P < 0.001). LH was found to have the greatest independent ability to predict free T, followed by insulin, then age and BMI z-score. Pubertal group was not an independent predictor of free T. We conclude that morning LH and fasting insulin are significant predictors of free T in obese girls, even after adjusting for potential confounders (age, pubertal group, adiposity). We suggest that abnormal LH secretion and hyperinsulinemia can promote HA in some peripubertal girls with obesity.
青春期前女孩的肥胖与高雄激素血症（HA）有关，高雄激素血症可能是多囊卵巢综合征（PCOS）的前兆。然而，并非所有肥胖女孩都表现出 HA，肥胖女孩中 HA 的决定因素仍不清楚。我们假设胰岛素和黄体生成素（LH）是肥胖女孩游离睾酮（T）浓度的独立预测因子。为了进一步评估这一点，从处于青春期不同阶段的 92 名肥胖（BMI-年龄百分位≥95）女孩中采集了空腹早晨血样。然后使用多元回归模型，将游离 T（因变量）、LH、胰岛素、青春期组（早期、中期或晚期青春期）、BMI z 评分和年龄作为自变量。在每个青春期组中，肥胖女孩的游离 T 浓度差异很大。该回归模型解释了肥胖女孩中游离 T 约一半的变异性（调整后的 R²=0.53，P<0.001）。LH 是预测游离 T 的最大独立因素，其次是胰岛素，然后是年龄和 BMI z 评分。青春期组不是游离 T 的独立预测因子。我们的结论是，即使在调整了潜在混杂因素（年龄、青春期组、肥胖程度）后，早晨 LH 和空腹胰岛素也是肥胖女孩游离 T 的重要预测因子。我们认为，异常的 LH 分泌和高胰岛素血症可能会促进一些肥胖青春期前女孩的 HA。
