• Density of rapid eye movements
• Changes of total percentage of REM sleep
• Changes in deep slow wave sleep (SWS)
• Number of night awakenings

The purpose of this study is to assess the effect of escitalopram on sleep architecture utilizing a prospective design.

Hypothesis: Escitalopram will improve REM latency in patients with MDD that have responded clinically to treatment.

Disturbance of sleep is a prominent symptom in depressive disorders. Alterations of sleep patterns in depressed patients include insomnia, frequent awakenings, early wake-up and non-refreshing sleep. Polysomnographic recordings have confirmed these reports, reporting reduced latency of the first REM episode of the night, with decreased density of rapid eye movements, and enhancement of total percentage of REM sleep, a reduction of deep slow wave sleep (SWS) and increase in night awakenings (Benca et al., Classification of sleep disorders).

The effects of antidepressant drugs on depression and sleep disorders, specifically SSRIs, have been thoroughly researched. The effects of escitalopram on sleep in depressed patients have been reported using a retrospective design, and in this proposed protocol, we suggest to assess the effect of escitalopram on sleep architecture utilizing a prospective design.

Hypothesis:

Escitalopram will improve REM latency in patients with MDD that have responded clinically to treatment.

• Drug: Escitalopram
• Procedure: A baseline overnight polysomnography (oPSG)

• Benca RM, Obermeyer WH, Thisted RA, Gillin JC. Sleep and psychiatric disorders. A meta-analysis. Arch Gen Psychiatry. 1992 Aug;49(8):651-68; discussion 669-70.
• Lader M, Andersen HF, Baekdal T. The effect of escitalopram on sleep problems in depressed patients. Hum Psychopharmacol. 2005 Jul;20(5):349-54.

Inclusion Criteria:

• Patients suffering from MDD, excluding a depressive episode of Bipolar Disorder.
• The depressive episode is not secondary to a general medical condition or substance abuse.
• Ages between 18-65 years old.
• Patients receiving other medications must be on a stable dosage for one month before entering the trial, including hypnotics.
• Able to understand and sign an informed consent form.

Exclusion Criteria:

• Patients suffering from sleep disturbances due to a physical condition (COPD, sleep apnea or essential insomnia preceding the diagnosis of depression).
• Patients suffering from an unstable clinically significant medical condition (cardiovascular, endocrine, nutritional, hepatic, urinary).
• Patients suffering from a malignancy or neuro-degenerative such as Parkinsons’ disease
• Patients suffering from a clinically significant psychiatric psychotic disease, as judged by DSM-IV criteria, such as schizophrenia or acute psychosis.
• Patients experiencing severe withdrawal symptoms following a discontinuation of hypnotic drugs, upon entry into the baseline phase.
• History of drug or alcohol dependence within the last year.