Diagnostic value of fasting insulin and insulin-like growth factor-1 levels in girls with central precocious puberty

Objectives: The gonadotropin-releasing hormone (GnRH) provocation test is crucial for diagnosing central precocious puberty (CPP). However, due to its invasion and high cost, it is essential to find a simpler biomarker. This study aimed to investigate the feasibility of fasting insulin (FINS) and insulin-like growth factor-1 (IGF-1) as potential biomarkers for diagnosing girls with CPP and to analyze their effects on puberty development. Methods: From May 2023 to June 2024, we retrospectively analyzed 145 girls in the growth clinic of the Third Affiliated Hospital of Zhengzhou University, including 80 CPP girls as the case group and 65 normal growth and development girls as the control group. Collect their growth and development parameters and blood samples. The levels of FINS, IGF-1, and sex hormones were detected and compared between the two groups. Results: Compared with the control group, girls in the CPP group showed higher levels of FINS, IGF-1, and IGF-1 standard deviation score (IGF-1 SDS) (p<0.001). Multivariate logistic regression analysis showed that the risk of CPP increased with the increase of FINS, IGF-1, and IGF-1SDS levels [OR=1.141, 95 % CI=(1.029-1.265), p<0.05; OR=1.062, 95 % CI=(1.011-1.116), p<0.05; OR=1.610, 95 % CI=(1.029-2.520), p<0.05]. The areas under the curve of FINS, IGF-1, IGF-1SDS, and their combination in the diagnosis of CPP were 0.759, 0.716, 0.707, and 0.777, respectively. Conclusions: Elevated FINS and IGF-1 levels in girls with CPP indicate their potential as effective biomarkers for early screening and diagnosis of CPP.