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

135 Atypical depression and bipolar spectrum45.4% versus 25.4% (P ¼ 0.0000). In another study, prevalence of BP-II in AD was64.2% (n ¼ 140). These findings are in line with previous reports (Perugi et al.,1998; Angst et al., 2003). Factor analysis of the Montgomery Asberg DepressionRating Scale (which has only two items negatively related to sleep and eating) in251 BP-II MDE and 306 UP MDE outpatients found three factors in BP-II, oneincluding reduced sleep (negative) and reduced appetite (negative). This factorwas not found in UP (Benazzi, 1997a, 1999a, 2000a, 2001a, b; Benazzi and Akiskal,2003a). Two studies, including only 10 BP-II and 28 BP-II, found no AD frequencydifference between BP and UP (Posternak and Zimmerman, 2002; Robertsonet al., 1996).Is BP-II versus UP difference in AD frequency age-related?UP MDE versus BP-II MDE had significantly higher age. BP-II MDE (n ¼ 187)versus UP MDE (n ¼ 126) had a significantly higher frequency of AD (49.7%versus 18.2%), persisting when controlled for age (Benazzi, 2003c). Findingssuggest that age may not be important for the BP-II versus UP difference in AD.Mitchell et al. (2001) suggested instead that BP versus UP depression differencescould be related to an age difference.Is there a difference in AD frequency in BP-II samples when probing forpast hypomania focused on overactivity?Frequency of BP-II MDE versus UP MDE increased when probing for pasthypomania, with the SCID-CV focused more on overactivity than on mood.This BP-II sample (n ¼ 103) had the same frequency of AD (47.5% versus45.4%) found in a previous BP-II sample interviewed strictly following theSCID-CV (n ¼ 251) (in the same setting and by the same interviewer), and asignificantly higher frequency of AD versus UP MDE (n ¼ 65, 16.9%: Benazzi andAkiskal, 2003a). Findings support the usefulness of probing for overactivity whenassessing past hypomania, as found by Angst et al.(2003) and Akiskal et al.(2001).The focus on past overactivity was also supported by a factor analysis study of pasthypomania using the Mood Disorder Questionnaire (MDQ) (Hirschfeld et al.,2000) in 181 remitted BP-II MDE and UP MDE, which found two factors, one ofwhich had only overactivity items (Benazzi and Akiskal, 2003b).Is AD frequency still higher in BP-II versus UP when BP-II had a short hypomania?In BP-II MDE with a history of hypomania lasting less than 4 days, frequency ofAD was significantly higher in comparison with UP MDE (Benazzi, 2001c),