Inclusion Criteria:  18 years and older Diagnosis of bipolar disorder with an index episode (IE) of depression with or without associated psychotic symptoms, according to the Diagnostic Manual of Mental Disorder 4th Edition Text Revision (DSM-IV-TR) Written informed consent to participate in the study Attending the Bipolar Disorder Program of the Psychiatry Service of the Hospital Clinic de Barcelona (Spain) for at least 6 months since the beginning of the index episode of the bipolar depression.  Exclusion Criteria:  Any serious or terminal medical organic disease Mental retardation (defined as an intelligence quotient <85) Electroconvulsive therapy