What is the Origin of HPA Axis Maladaptation?

This concept stems from the understanding of allostasis and allostatic load, where the body's attempt to maintain stability through change eventually leads to a physiological cost. The term highlights that the HPA axis, while designed for acute stress, can become maladapted under persistent psychological or metabolic pressure, moving beyond a simple "fatigue" model to a state of regulatory dysfunction.

What is the Mechanism of HPA Axis Maladaptation?

Maladaptation is driven by chronic, excessive input to the hypothalamus, leading to altered feedback sensitivity at the pituitary and hypothalamus, often involving glucocorticoid receptor downregulation. Initially, this results in hypercortisolism, but with prolonged stress, the adrenal glands may exhibit reduced responsiveness to ACTH. The core mechanism is a loss of the precise, negative feedback control that normally governs the rhythmic and appropriate release of stress hormones.

HPA Axis Maladaptation ∞ Area

HPA Axis Maladaptation

Meaning

HPA axis maladaptation refers to the Hypothalamic-Pituitary-Adrenal axis’s failure to maintain a healthy, dynamic response to chronic or overwhelming stress, resulting in an inappropriate or dysregulated secretion pattern of cortisol and DHEA. This is a state where the stress response system has become poorly calibrated, leading to either chronically elevated or blunted hormone levels, which significantly compromises systemic resilience. Clinical symptoms often include fatigue, immune dysregulation, and sleep disturbances.