title: Dissimilar morbidity following initial mania versus mixed-states in type-I bipolar disorder.
abstract: BACKGROUND
  Mixed-states of bipolar disorders (BPD) may predict worse future illness and more depressive than manic morbidity, challenging a tendency to conflate mixed-states and mania.
  
  
  METHODS
  Patients (N=247) were followed-up systematically for 24 months following hospitalization for initial major episodes of DSM-IV type-I BPD and scored for weekly interval morbidity-types.
  
  
  RESULTS
  Overall morbidity during follow-up was 1.6-times greater following mixed (n=97) versus manic (n=150) first-episodes of BPD (60.0 vs. 37.8%-of-weeks; p<0.0001). Patients with initial mixed-states had a nearly 12-fold later excess of mixed-states, 6.5-times more major depression, and 69% more dysthymia during follow-up than those presenting in mania. In contrast, manic first-episodes were followed by over 10-times more mania, 6-times more hypomania, and 35% more psychotic illness.
  
  
  CONCLUSIONS
  Estimates of longitudinal morbidity may be inaccurate, and ongoing treatment may distort them.
  
  
  CONCLUSIONS
  Based on detailed, prospective assessments among first-episode BPD patients, those presenting in mixed-states were more ill, and much more likely to experience mixed, depressive and dysthymic morbidity during follow-up, versus much more mania, hypomania, and perhaps more psychosis following mania. The findings support two markedly dissimilar subtypes of BPD, and call for more explicit therapeutic studies of mixed-states.
authors.affiliation: Department of Psychiatry, Harvard Medical School, Boston, MA, USA.
authors.forename: Ross J
authors.initials: RJ
authors.lastname: Baldessarini
authors.forename: Paola
authors.initials: P
authors.lastname: Salvatore
authors.forename: Hari-Mandir Kaur
authors.initials: HM
authors.lastname: Khalsa
authors.forename: Mauricio
authors.initials: M
authors.lastname: Tohen
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001714:Bipolar Disorder / Q000523:psychology*; D016009:Chi-Square Distribution; D003865:Major Depressive Disorder / Q000523:psychology; D018450:Disease Progression; D019263:Dysthymic Disorder / Q000523:psychology; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D011569:Psychiatric Status Rating Scales; D013997:Time Factors