Cognitive impairment in bipolar disorder: How close to dementia?

Area of Science:

• Neuroscience
• Psychiatry
• Cognitive Psychology

Background:

• Bipolar disorder (BD) is a severe mental illness characterized by significant cognitive and functional impairments.
• Understanding the heterogeneity of these impairments is crucial for effective management and treatment.

Purpose of the Study:

• To evaluate the heterogeneity of cognitive and psychosocial functioning in bipolar disorder.
• To compare cognitive performance between individuals with BD and those with major neurocognitive disorder (dementia).
• To identify factors associated with cognitive dysfunction in BD.

Main Methods:

• Cross-sectional study of 108 individuals with BD and 39 with major neurocognitive disorder.
• Cognitive and functional status assessed using MoCA, neuropsychological tests, and FAST.
• BD participants classified into three cognitive-functional profiles: Dementia-like (BD-DL), Mild (BD-M), and Preserved (BD-P).

Main Results:

• Significant group differences in neuropsychological tests were observed (MANCOVA, p < 0.001).
• The BD-P group demonstrated superior performance in fluency and verbal memory compared to BD-DL and Dementia groups.
• Younger age, lower hypertension rates, and fewer depressive symptoms were linked to better cognitive profiles (BD-P, BD-M).

Conclusions:

• Distinct cognitive-functional subgroups exist within bipolar disorder.
• Cognitive deficits in BD can be as severe as those observed in dementia.
• Identifying these subgroups and associated factors can inform targeted interventions for cognitive dysfunction in BD.