Recurrent unipolar mania: A comparative, cross-sectional study

A significant number of patients experience recurrent episodes of mania without depressive episodes. Evidence from the available literature suggests that these patients differ from typical "bipolar" or "manic-depressive" patients, but results have been inconsistent. The current study aims to add to this literature by comparing the demographic, clinical and risk factor profiles of patients with recurrent mania with and without depression.

66 patients with a diagnosis of bipolar I disorder were divided into "unipolar mania" (recurrent mania alone, MA) and "bipolar" (both mania and depression, MD) sub-groups. Comorbid diagnoses were assessed using the Mini International Neuropsychiatric Interview (MINI), and genetic and environmental risk factors were explored using the Diagnostic Interview for Genetic Studies (DIGS), Childhood Trauma Questionnaire (CTQ), and an additional questionnaire designed for the purpose of the study. Differences between the MA and MD groups in terms of demographic variables, clinical profile, comorbidities and antecedent risk factors were explored.

Patients with both mania and depression had higher frequencies of lifetime suicide attempts, antidepressant treatment, and catatonic symptoms. There was some evidence of an association between overcrowding in childhood and the presence of depressive episodes. No other differences in demographic, clinical or risk factor variables could be found between the two groups.

Our results are consistent with the view that unipolar mania is not a distinctive disorder, or even a distinctive subtype of bipolar disorder. However, this conclusion is provisional as it is based only on clinical and demographic data.