Bipolar Disorders: Mixed States, Rapid-Cycling, and Atypical Forms

58 G. Perugi and H. S. AkiskalMixed states have re-emerged as a new focus of research in affective disorders,and future investigations from other centers will be important in extending thefindings and conceptual advances described herein. Only one study (Cassidy et al.,2001) has been published on the stability of MS over prospectively examinedfollow-up of interepisode duration of 6 months. Therefore, prospective studieswill be particularly informative in future research on MS.REFERENCESAkiskal, H. S. (1992). The mixed states of bipolar I, II, III. Clin. Neuropsychopharm., 15(suppl. 1a), 632–3.Akiskal, H. S. (1994). Dysthymic and cyclothymic depressions: therapeutic considerations.J. Clin. Psychiatry., 55 (suppl.), 46–52.Akiskal, H. S. and Benazzi, F. (2003). Family history validation of the bipolar nature ofdepressure mixed states. J. Affect. Disord., 73, 113–22.Akiskal, H. S. and Mallya, G. (1987). Criteria for the ‘‘soft-bipolar spectrum’’: treatmentimplications. Psychopharm. Bull., 23, 68–73.Akiskal, H. S., Khani, M. K., and Scott-Strauss, A. (1979). Cyclothymic temperamental disorders.Psychiatr. Clin. North Am., 2, 527–54.Akiskal, H. S., Maser, J. D., Zeller, P., et al. (1995). Switching from ‘‘unipolar’’ to ‘‘bipolar II’’: an11-year prospective study of clinical and temperamental predictors in 559 patients. Arch. Gen.Psychiatry., 52, 114–23.Akiskal, H. S., Hantouche, E. G., Bourgeois, M. L., et al. (1998). Gender, temperament, and theclinical picture in dysphoric mixed mania: findings from a French national study (EPIMAN).J. Affect. Disord., 50, 175–86.American Psychiatric Association (1987). Diagnostic and Statistical Manual of Mental Disorders,3rd edn, revised (DSM-III-R). Washington, DC: APA.American Psychiatric Association (1994). Diagnostic and Statistical Manual of Mental Disorders,4th edn (DSM-IV). Washington, DC: APA.Bauer, M. S., Whybrow, P. C., Gyulai, L., Gonnel, J., and Yeh, H. S. (1994). Testing definitions ofdysphoric mania and hypomania. Prevalence, clinical characteristics and inter-episode stability.J. Affect. Disord., 32, 201–11.Benazzi, F. (2000). Depressive mixed states: unipolar and bipolar II. Eur. Arch. Psychiatry Clin.Neurosci., 250, 249–53.Benazzi, F. and Akiskal, H. S. (2001). Delineating bipolar II mixed states in the Ravenna–SanDiego collaborative study: the relative prevalence and diagnostic significance of hypomanicfeatures during major depressive episodes. J. Affect. Disord., 67, 115–22.Berner, P., Gabriel, E., Katschning, H., Kufferle, B., and Lenz, G. (1983). The Viennese conceptof endogenomorphic axial syndromes. In Psychiatry: the State of the Art, ed. P. Pichot,P. Berner, R. Wolf, and K. Thau, pp. 113–14. New York: Plenum Press.Berner, P., Gabriel, E., Katschnig, H., et al. (1993). Diagnostic Criteria for Functional Psychoses,2nd edn. New York: Cambridge University Press.