Bipolar disorder highest in epilepsy patients

Authors of a recent report say neurologists may be surprised by their survey results, which showed that 12% of epilepsy patients exhibited bipolar symptoms. The report describes findings from a survey involving 85,358 people who had been sent the Mood Disorder Questionnaire (MDQ), a validated self-report instrument that screens for the presence of a lifetime history of bipolar disorder. The MDQ was accompanied by questions about current health problems, including epilepsy, migraine, asthma and diabetes mellitus and sent to participants chosen from a list of 600,000 US households and representing the US adult population based on selected demographic variables. Bipolar symptoms were 1.6 to 2.2 times more likely to occur in respondents with epilepsy than in those with migraine, asthma, or diabetes mellitus, and 6.6 times more likely than in the healthy comparison group. Just under half of the patients with epilepsy who had reported bipolar symptoms had received a prior diagnosis of bipolar disorder, around a quarter had been diagnosed with unipolar depression and a quarter had received no diagnosis with respect to their mental state.The authors say it's concerning that a large proportion of patients reporting bipolar symptoms had been diagnosed with unipolar depression. "This is important since effective treatments for depression and bipolar disorder are different and administration of antidepressants to patients with bipolar disorder can precipitate worse psychiatric complications including mania or rapid cycling," they sayHowever, they also acknowledge the possibility that the MDQ is highlighting symptoms associated with interictal dysphoric disorder (IDD) rather than capturing symptoms of bipolar disorder. They say, "Future studies utilizing structured interviews would be helpful to elucidate whether epilepsy patients meet formal criteria for bipolar disorder or are meeting MDQ criteria on the basis of IDD." While this study focused on bipolar disorder, clinicians should remember that rates of depression, anxiety and psychosis may actually exceed rates of bipolar disorder, the authors note.Reference...