The continuum/spectrum concept of mood disorders: is mixed depression the basic link?
- 147 Downloads
Mixed states, i.e., opposite polarity symptoms in the same mood episode, question the bipolar/unipolar splitting of mood disorders, and support a spectrum view. Study aim was assessing the distribution of intradepressive hypomanic symptoms between bipolar-II (BP-II) and major depressive disorder (MDD) depressions, and testing a dose–response relationship between number of intradepressive hypomanic symptoms and bipolar family history. No bi-modality, and a dose–response relationship, would not support a categorical distinction.
Consecutive 389 BP-II and 261 MDD depressed outpatients were interviewed by the structured clinical interview for DSM-IV, hypomania interview guide, and family history screen, by a mood specialist psychiatrist, in a private practice. Intradepressive hypomanic symptoms were systematically assessed. Mixed depression was defined as the combination of depression and three or more intradepressive hypomanic symptoms, a validated definition.
BP-II, versus MDD, had significantly more intradepressive hypomanic symptoms. The distribution of intradepressive hypomanic symptoms between BP-II and MDD was not bi-modal but normal-like, and a dose–response relationship was found between the number of intradepressive hypomanic symptoms and bipolar family history.
Study findings question the categorical division of BP-II and MDD, and may support the spectrum view of mood disorders.
Keywordsmajor depressive disorder bipolar II disorder spectrum mixed depression depressive mixed state
- American Psychiatric Association (2000) Diagnostic and statistical manual of mental disorders, 4th edn, text revision (DSM-IV-TR). American Psychiatric Association, Washington, DCGoogle Scholar
- Armitage P, Berry G, Matthews JNS (2002) Statistical methods in medical research. Blackwell Science, Oxford, UK, pp 87–88Google Scholar
- Benazzi F (2005a) The relationship of major depressive disorder to bipolar disorder: continuous or discontinuous? Curr Psychiatry Rep 7:462–470Google Scholar
- First MB, Spitzer RL, Gibbon M, Williams JBW (1997) Structured clinical interview for DSM-IV axis I disorders-clinician version (SCID-CV). American Psychiatric Press, Washington, DCGoogle Scholar
- Williams JBW, Terman M, Link MJ, Amira L, Rosenthal NE (1994) Hypomania interview guide (including hyperthymia). Current assessment version (HIGH-C). Clinical Assessment Tools Packet, Center for Environmental Therapeutics, Norwood, NJGoogle Scholar