Correlations among bone mineral density, insulin-like growth factors and biochemical bone markers in healhty female subjects

Insulin-like growth factor-I (IGF-I) is an anabolic factor for osteoblasts. A positive relationship between bone mineral density (BMD) and circulating IGF-I levels suggest that IGF-I has an endocrine effect on increasing bone mass. In this study, plasma IGF-I and IGF-II were determined in relation to BMD and biochemical bone markers in 228 healthy female subjects. Both BMD and plasma IGF-I levels declined with age. There was no significant correlation between plasma IGF-I levels and BMD, and between plasma IGF-I levels and either plasma carboxy-terminal propeptide of type I procollagen (PICP) or pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP) levels. It is suggested, therefore, that the decline in plasma IGF-I levels has little contribution to the decrease in BMD in healthy aged women and that the agerelated decrease in plasma IGF-I levels are not associated with changes in biochemical bone markers.