The overlap between personality disorders and major depressive disorder (MDD).
BACKGROUND
Research studies have focused attention on the importance of the comorbidity of personality disorders and depression.


METHODS
The present review examines seven potential explanations for the overlap to clarify the nature of the relationship, if any, between depression and personality disorder diagnoses.


RESULTS
There may be many explanations for the potential overlap of personality disorders (PD) and major depressive disorder (MDD). For example, the distinction between states and traits may not be as clear and definitive as suggested in the DSM-IV. In some cases, depression may influence personality pathology, and may even lead to personality disorders. In other cases, personality disorders may lead to MDD.


CONCLUSIONS
Further research may clarify the nature of the relationship, if any, between depression and personality disorder diagnoses, as well as the relationship between comorbidity and treatment response.
Farabaugh
Amy
A
The Depression Clinical and Research Program, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA. afarabaugh@partners.org
Mischoulon
David
D
Fava
Maurizio
M
Guyker
Wendy
W
Alpert
Jonathan
J
D015897:Comorbidity; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000523:psychology*; D003937:Diagnosis, Differential; D039721:Diagnostic and Statistical Manual of Mental Disorders; D006801:Humans; D010554:Personality Disorders / Q000175:diagnosis / Q000523:psychology*; D012307:Risk Factors