An Investigation of the Sleep Architecture and Consequent Cognitive Changes in Olanzapine-Treated Depressed Patients

OBJECTIVES: Primary Objective: To assess the objective (polysomnographic) changes in sleep quality before and after introduction of olanzapine in treatment of patients with depression. Secondary Objectives: To assess the subjective changes in sleep quality parameters before and at different stages after introduction of olanzapine in treatment, longitudinally, and to correlate these changes with measures of illness severity and changes in cognition. STUDY DESIGN: Prospective, double blind, randomized polysomnographic (PSG) study of patients before and after treatment with olanzapine. PSG recordings will be done three times throughout the study: before starting olanzapine augmentation (baseline), at day 3 to 5 (acute) and day 28 to 31 (chronic). PSG will be completed at patients' homes with a portable PSG. Psychiatric scales, subjective sleep quality scales, and cognition measurements will be completed at each visit.