Bipolar Disorder Characterized By Recurrent Symptoms
A new 5-year naturalistic study finds the course of bipolar disorder is rarely chronic, but recurrences are highly common, according to a new report published in the journal Bipolar Disorders.
A team of researchers from the University of Helsinki, Finland, find chronicity, or extended un-interrupted episodes, were seen in only 1.3% of the 156 patients with bipolar I or II disorder included in the study. However, the researchers also found the 87% of the participants experienced recurrent symptoms or episodes, with nearly half of those experiencing three or more recurrences.
“As a consequence, the patients spent almost one-third of the time in illness episodes and about one-sixth of the time with subthreshold symptoms”, said study author Erkki Isometsä.
For the study, the patients were interviewed in a baseline assessment, and then again at 6 months, 18 months, and 5 years later using a life-chart method to evaluate changes in mood states.
By the time of the 5-year check-in, 96% of participants had reached full remission for periods of at least 2 months. In multivariate analysis depression and comorbid cluster C personality disorders were found to be “powerful predictors for outcome”.
The researchers noted lifetime psychotic symptoms were the only factor included in the assessment to reliably predict recurrence. Individuals with such symptoms experienced recurrences at a median 4.0 months, compared to 5.7 months in those without these symptoms.
The patients most commonly experienced mood states characterized by depression, but researchers were surprised to find the patients with bipolar II disorder did not spend more time in depressive states compared to the bipolar I disorder patients.
“Similar proneness to depression may appear counterintuitive to clinicians, who mostly treat patients with [bipolar disorder]-II only for depression, whereas the florid albeit short-lived manic states of patients with [bipolar disorder]-I commonly dominate their perceived clinical picture”, the team comments.