Background: While some prior studies have found higher rates of psychotic depression in those with bipolar disorder or a bipolar relative, others have failed to confirm these observations. We examined the relationship of psychotic depression to polarity in several large familial samples of mood disorder.
Methods: A total of 4,724 subjects with major mood disorder in three family studies on the genetics of bipolar I disorder (BPI) or recurrent major depressive disorder (MDDR) were administered semi-structured interviews by clinicians.
Objective: The purpose of this study was to assemble and validate a database of phenotypic variables that were collected from families with bipolar disorder as a resource for genetic and other biological studies.
Method: Participants were ascertained for two bipolar disorder genetic linkage studies: the University of Chicago, Johns Hopkins, and National Institute of Mental Health (NIMH) Intramural Program (CHIP) Collaboration and the NIMH Genetics Initiative project. All participants underwent detailed, phenotypic assessment with either the Schedule for Affective Disorders and Schizophrenia-Lifetime Version or one of four versions of the Diagnostic Interview for Genetic Studies.