Long-term inter-episode stability of syndromes underlying mania

Objective: To explore the stability of diverse manic presentations across manic recurrences. Method: A total of 253 bipolar patients who experienced two or more hospitalizations, because of consecutive manic ( or mixed) episodes, during a 20-year period were included. All patients had second hospitalizations with an mean interval of 773 days, while 126 and 91 patients had third and fourth hospitalizations with mean intervals of 1559 and 2237 days from the index hospitalization, respectively. Seven symptom scores, previously factor-validated, were calculated. Results: Depressive mood, irritable aggression, psychomotor/thought inhibition, mania, emotional lability/agitation and psychosis were moderately correlated across the index and subsequent hospitalizations. Conclusion: A majority of diverse manic presentations were stable across manic recurrences. The stability was not restricted to two consecutive recurrences but appeared widespread over the long-term course of bipolar disorder. The finding may serve for the development of more effective long-term treatment strategies and a clinically more reasonable subtyping of mania.