Insulin-like growth factor 1 and insulin-like growth factor-binding protein 3 in central precocious puberty: a systematic review and meta-analysis

To identify distinct patterns of insulin-like growth factor-1 (IGF-1) and insulin-like growth factor-binding protein 3 (IGFBP-3) in girls with central precocious puberty (CPP), and to compare IGF-1 and IGFBP-3 levels in patients with CPP and precocious thelarche (PT). A literature search of PubMed, Embase, and Scopus databases was done to identify observational studies. Newcastle-Ottawa Scale (NOS) was used to assess the quality of the studies. Pooled weighted mean difference (WMD) and 95% confidence intervals (CI) were reported. Fourteen studies were included. As opposed to age-matched or similar-aged pre-pubertal girls, patients with CPP had significantly higher levels of IGF-1 and IGFBP-3. CPP was associated with higher levels of IGF-1 approaching statistical significance but similar levels of IGFBP-3 compared to PT. Distinct hormonal patterns, such as elevated IGF-1 and IGFBP-3, were identified in patients with CPP, suggesting a potential diagnostic value of IGF-1 and IGFBP-3 levels.