Discrete neurocognitive subgroups in fully or partially remitted bipolar disorder: Associations with functional abilities

- Three subgroups with unique neurocognitive profiles were found in bipolar disorder.
- Intact cognitive function was found in 46% patients.
- Subgroups with global (21%) or selective (33%) deficits had most functional problems.
- There is need for a more tailored treatment targeting cognition in bipolar disorder.

BackgroundNeurocognitive impairment in remitted patients with bipolar disorder contributes to functional disabilities. However, the pattern and impact of these deficits are unclear.MethodsWe pooled data from 193 fully or partially remitted patients with bipolar disorder and 110 healthy controls. Hierarchical cluster analysis was conducted to determine whether there are discrete neurocognitive subgroups in bipolar disorder. The pattern of the cognitive deficits and the characteristics of patients in these neurocognitive subgroups were examined with analyses of covariance and least significance difference pairwise comparison.ResultsThree discrete neurocognitive subgroups were detected: one that was cognitively intact (46.1%), one that was selectively impaired with deficits in processing speed (32.6%), and one that was globally impaired across verbal learning, working memory, and executive skills (21.2%). The globally and selectively impaired subgroups were characterized by greater perceived stress and subjective cognitive complaints, poorer work and social adjustment, and reduced quality of life compared to patients who were cognitively intact.LimitationsThe study design was cross-sectional which limits inferences regarding the causality of the findings.ConclusionGlobally and selectively impaired bipolar disorder patients displayed more functional disabilities than those who were cognitively intact. The present findings highlight a clinical need to systematically screen for cognitive dysfunction in remitted bipolar disorder and to target residual cognitive dysfunction in future treatment strategies.