Research

Hormonal

Chronic insomnia is associated with a 24-hour hypersecretion of ACTH and cortisol (HPA axis activation) that retains a normal circadian rhythm, indicating a disorder of central nervous system hyperarousal rather than simple sleep loss.

Chronic insomnia is not just about not sleeping; it is a state of constant physiological stress (high cortisol/ACTH) that persists day and night. Treatment should focus on reducing this overall physiological and emotional hyperarousal, not just on improving sleep duration or using standard hypnotics. Consider therapies that target stress system down-regulation.

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We conclude that insomnia is associated with an overall increase of ACTH and cortisol secretion, which, however, retains a normal circadian pattern. These findings are consistent with a disorder of central nervous system hyperarousal rather than one of sleep loss, which is usually associated with no change or decrease in cortisol secretion or a circadian disturbance.
Alexandros N. Vgontzas · The Journal of Clinical Endocrinology & Metabolism · 2001

Why this rating

Controlled study with matched controls, objective polysomnography, and serial blood sampling, though small sample size (n=24).

Source

Chronic Insomnia Is Associated with Nyctohemeral Activation of the Hypothalamic-Pituitary-Adrenal Axis: Clinical Implications

Alexandros N. Vgontzas · The Journal of Clinical Endocrinology & Metabolism · 2001

DOI 10.1210/jc.86.8.3787

cross_sectional · n=24Cited 188×
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DOI resolved against Crossref · corpus check 2026-06-10

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