Cognitive and affective theory-of-mind impairment in people with early-stage bipolar disorder

Literature suggests impaired theory-of-mind (ToM) in people with bipolar-disorder (BD). However, prior research primarily examined patients at chronic stage (stage 3c-4) and was constrained by clinical heterogeneity. Deficits in ToM modalities remain to be clarified. We aimed to assess cognitive and affective ToM performance in euthymic people with early-stage BD.

Cognitive and affective ToM were examined in 41 euthymic early-stage (stage 2-3b) BD patients aged 16 - 40 years who were treated within three-years from first-episode mania and 40 demographically-matched healthy controls, using Faux-pas task (FPT) and Reading the Mind in the Eyes test (RMET). Relationships of ToM performance with symptom severity, cognitive functions, history of psychosis and depressive episode were assessed.

Participants displayed significantly lower scores than controls in both cognitive and affective ToM components in FPT. The two groups showed comparable performance in RMET. No significant correlations were observed between ToM measures and variables of symptom dimensions, cognitive functions and treatment variables in BD patients. Additional analyses revealed no significant differences in ToM performance in FPT and RMET between BD patients with versus without a history of psychosis, and between BD patients with versus without a history of depressive episode.

This study extends previous findings of ToM deficits in later-stage BD to euthymic people with early-stage BD who exhibit cognitive and affect ToM impairment. Further research is needed to clarify potential differential trajectories of cognitive and affective ToM deficits and their relationships with psychosis, polarity of mood episodes, and functional outcomes in early-stage BD.