Abstract
Objectives:
An emerging literature has assessed cognition or imaging markers of brain health in in older age bipolar disorder (OABD). In this context, we conducted the first longitudinal study (to our knowledge) that assessed the relationship among cognition, mood symptoms, and imaging markers of brain health in OABD.
Methods:
99 participants with OABD were enrolled, underwent baseline assessment, and were followed annually for up to 3 years. They completed comprehensive assessments that included evaluation of general medical status, vascular disease burden, mental status, cognitive performance. A subset of participants (n = 58) completed magnetic resonance imaging (MRI) at one or two time-points, yielding three measures of brain health: gray matter volume, fractional anisotropy (FA), and burden of white matter hyperintensities (WMH).
Results:
Group-based trajectory modelling (GBTM) of overall cognitive performance revealed two groups: a group with higher cognitive performance (63 of 99, 63.6%) and a group with lower cognitive performance (36 of 99, 36.4%). GBTM also revealed two groups based on each of the three imaging markers of brain health. The higher cognitive performance group was associated with the groups with higher measure of total gray matter or higher FA. We found no relationship between the cognitive groups and level of mood symptoms during longitudinal follow-up or WMH burden.
Conclusions:
In this first longitudinal study of cognition, mood symptoms, and markers of brain health in OABD, cognitive performance was related to brain health and not to mood symptoms over a follow-up of up to three years. Almost two-thirds of participants with OABD had cognitive performance comparable to older adults without OABD. Larger future studies will need to replicate and extend these findings.
Plain Language Summary Title
A Longitudinal Study of Cognition, Mood, and Brain Health in Older Adults with Bipolar Disorder
Plain Language Summary
This study examined cognitive performance, mood symptoms, and brain health markers in 99 adults with bipolar disorder ages 50 years and older who were assessed annually for up to 3 years. Brain imaging was available in 58 of the participants. While previous research has suggested that repeated bipolar mood episodes might cause brain changes and cognitive decline (“neuroprogression”), this study found that most older adults with bipolar disorder maintained relatively normal cognitive performance. The study findings suggest that significant cognitive decline may occur only in a subset of patients with bipolar disorder as they age. To our knowledge, this is the first longitudinal study that examined the relationship between cognition, mood symptoms, and brain imaging markers together in older adults with bipolar disorder.
Get full access to this article
View all access options for this article.