Prediction Models for Insulin Resistance in Girls with Premature Adrenarche

Abstract

Aim: The purpose of this study was to develop an accurate regression model to predict insulin resistance in girls with premature adrenarche. Methods: The insulin sensitivity index was calculated from the frequently sampled intravenous glucose tolerance test with tolbutamide. Thirty-five prepubertal girls (23 Caribbean-Hispanic and 12 African-American; mean age 6.8 years) were studied. The insulin sensitivity index was compared to birth weight, body mass index (BMI), the presence of acanthosis nigricans (AN), insulin-like growth factor 1, insulin-like growth factor binding protein 1, sex hormone binding globulin, lipid profile, and adrenocorticotropic hormone stimulated androgens. Results: The best prediction models included birth weight, BMI, and AN (model 1: R² = 0.78) and BMI, AN, and serum 17-OH pregnenolone (model 2: R² = 0.76). When viewed as screening tests, a cutoff value <5.5 (premature adrenarche insulin resistance score) in both equations showed a sensitivity of 100% and a specificity of 85%. Conclusion: Born small for gestational age, premature adrenarche, obesity, AN, and higher serum 17-OH pregnenolone levels may confer negative, but independent, health risks.