Mood alterations and sleep.

We have reviewed literatures about neurobiological aspect of mood disorders in the light of abnormalities of REM sleep. A shortened REM latency is a consistent finding in depressed patients and may be considered a biological marker for depression. Most depressed patients with shortened REM latency also show non-suppression on dexamethasone-suppression test (DST). The commonly used antidepressant drugs cause a significant reduction in REM sleep. Patients with abnormal DST show a better response to sleep deprivation than those with normal DST. Recent studies indicated that borderline patients, primary dysthymic patients and obsessive-compulsive patients (OCD) have shortened REM latency. Farthermore, patients with OCD have a fairly good response to antidepressant clomipramine. Diagnostic and therapeutic strategies can conceivably be related on the examination of sleep patterns of psychiatric patients.