What is the Origin of Sustained IGF-I Elevation?

This is a clinical term, combining Sustained, meaning prolonged and continuous, with IGF-I, the key mediator of Growth Hormone action, and Elevation, denoting a concentration above the healthy physiological range. It is a marker of endocrine overstimulation.

What is the Mechanism of Sustained IGF-I Elevation?

IGF-I is primarily produced by the liver in response to pulsatile GH secretion, acting as an endocrine mediator. Sustained elevation mechanistically drives unchecked cellular proliferation and inhibits apoptosis, increasing the risk for abnormal tissue growth. Furthermore, chronic high levels can lead to downregulation of the insulin receptor and post-receptor defects, contributing to a state of systemic insulin resistance and metabolic dysfunction.

Sustained IGF-I Elevation ∞ Area

Sustained IGF-I Elevation

Meaning

A chronic, pathologically high concentration of Insulin-like Growth Factor-I (IGF-I) in the systemic circulation, often resulting from a pituitary adenoma (acromegaly) or, in the context of exogenous therapy, from an inappropriately high or frequent dose of Growth Hormone (GH). While IGF-I is anabolic, sustained, supraphysiological elevation is associated with increased risk of certain malignancies, insulin resistance, and cardiovascular complications, representing a departure from optimal hormonal health. Clinical management focuses on normalization.