Can chronic stress and anxiety impair sleep through hyperarousal?

Chronic stress and anxiety commonly coexist with insomnia symptoms and fit the multidomain hyperarousal model of insomnia. Overall, the proposed pathway is biologically and clinically credible, but direct long-term causal evidence is strongest for physiological arousal impairing sleep continuity rather than for every link in the full chain.

Clinical and sleep-continuity evidence

• Anxiety disorders are associated with insomnia complaints; generalized anxiety is particularly associated with difficulty maintaining sleep.
• The clearest directional finding comes from a 15-day within-person study: higher presleep cortisol predicted lower sleep efficiency and shorter sleep. Sleep efficiency is a core measure of sleep continuity, reflecting time asleep relative to time in bed.
• Reviews similarly identify more awakenings and reduced sleep efficiency as relatively robust features of insomnia, although objective polysomnography findings are variable across studies and individuals.

Hyperarousal mechanisms

• Cognitive-emotional activation—sleep-related worry, repetitive presleep thinking, and heightened attention to sleep—is a central feature of insomnia models.
• Physiological activation is also implicated. Cortisol elevations provide one measurable marker, although autonomic findings are inconsistent and not all people with insomnia show the same physiological profile.
• Cognitive hyperarousal plausibly contributes to fragmented and nonrestorative sleep, while physiological arousal may reduce restoration indirectly through shorter, less continuous sleep. Direct evidence specifically measuring “restorative sleep” remains less established than evidence for continuity.

Reciprocal clinical implications

• The relationship can become self-reinforcing: evening stress predicts shorter sleep, while greater wake after sleep onset and lower sleep efficiency predict greater next-day perceived stress.
• For persistent insomnia, CBT-I is the recommended first-line treatment; its cognitive, behavioral, and relaxation/counter-arousal elements directly target this cycle.

Bottom line

• The claim is plausible with moderate confidence: stress/anxiety-related hyperarousal likely contributes to poor sleep, with the best evidence supporting physiological arousal—particularly elevated presleep cortisol—as a predictor of worse sleep continuity.