Is chronic insomnia a precursor to major depression? Epidemiological and biological findings

Curr Psychiatry Rep. 2012 Oct;14(5):511-8. doi: 10.1007/s11920-012-0308-5.


Insomnia has been found to be a clinical predictor of subsequent depression. Nevertheless the biological processes underlying this causal relationship are yet not fully understood. Both conditions share a common imbalance of the arousal system. Patients with insomnia present fragmented REM sleep, which probably interferes with basal processes of emotion regulation. The interaction between the arousal and the affective system with the persistence of the disorder could slowly alter also the cognitive system and lead to depression. Although preliminary results seem to support this hypothesis, data are still too few to make valid conclusions.

Publication types

  • Review

MeSH terms

  • Arousal / physiology
  • Chronic Disease
  • Cognition / physiology
  • Comorbidity
  • Depressive Disorder, Major / epidemiology
  • Depressive Disorder, Major / etiology*
  • Depressive Disorder, Major / physiopathology
  • Emotions / physiology
  • Humans
  • Sleep Initiation and Maintenance Disorders* / epidemiology
  • Sleep Initiation and Maintenance Disorders* / physiopathology
  • Sleep, REM / physiology