Background: Of all the psychiatric
disorders associated with insomnia, depression is the
most common. It has been estimated that 90% of patients with depression complain about sleep
quality. Since the first reports of short rapid
eye movement (REM) latency in depressed patients and of the effect of sleep deprivation on
depression in the 1970s, numerous sleep studies
have provided extensive observations and
theoretical hypotheses concerning the etiology and
pathophysiology of depression. The aim of this
review is to summarize knowledge regarding the
relationships between sleep and depression.
Data Sources and Selection: MEDLINE
and PsycINFO searches of the literature published
in English or French between 1964 and 2005 that examined the relationships between sleep
disturbance and depression were conducted. Search terms used were depression, depressive disorder, affective disorder, mood disorders, seasonal
affective disorder, sleep, sleep disorders,
insomnia, REM, polysomnography, sleep deprivation,
electroencephalography, PET, SPECT, and fMRI.
Data Synthesis: Two hundred five
papers were identified and selected and then
integrated into the following categories: sleep
architecture, antidepressive therapies, age- and
gender-associated differences, functional imaging results,
and sleep-related hypotheses explaining the pathophysiology of depression.
Conclusion: Numerous studies provide
findings indicating the remarkable relationship between sleep alterations and depression.
Although the existing hypotheses are not likely to
explain all aspects of the sleep alterations in
depression, each may be worth being maintained for
refinements of pathophysiologic models of
depression as new data accumulate. Further research
taking into account the heterogeneity of depressive
disorder and linking the different areas of research
is needed to develop more comprehensive theoretical models and new therapies for depression.
J Clin Psychiatry 2005;66(10):1254-1269
© Copyright 2005 Physicians Postgraduate Press, Inc.