Social cognition and neurocognition in first-episode bipolar disorder and psychosis: The effect of negative and attenuated positive symptoms

Background: Schizophrenia and bipolar disorder are associated with neurocognitive and social-cognitive impairments. To date very few studies investigated social cognition in first-episode bipolar disorder (FEBD). Our main aim was to investigate the differences in social cognition and neurocognition between FEBD and firstepisode psychosis (FEP). Another aim was to investigate neurocognitive correlates of negative symptoms and attenuated psychotic symptoms in FEBD. Methods: This study included 55 FEBD, 64 FEP and 43 healthy controls. A comprehensive neuropsychological battery assessing social cognition, processing speed, verbal and visual memory, working memory, sustained attention, and executive functions was administered to all participants. Results: Both FEBD and FEP were associated with widespread deficits in all neurocognitive domains and social cognition. Both FEP (d = -1.19) and FEBP (d = -0.88) were also impaired in social cognition. In FEP, effect sizes (Cohen's d) of neurocognitive deficits ranged from -0.71 to -1.56. FEBD was also associated with relatively milder but similar neurocognitive deficits (d = -0.61 to-1.17). FEBD group performed significantly better than FEP group in verbal and visual memory, processing speed, and executive function domains (d = -0.40 to-0.52). Negative symptoms and social functioning were associated with neuropsychological impairment in both groups. The severity of attenuated psychotic symptoms was associated with poorer verbal memory in FEBD (r = -0.39, p < 0.01). Limitations: The cross-sectional nature of the current study is the main limitation. Conclusions: Neurocognitive and social-cognitive deficits are evident in both FEBD and FEP. In FEBD, more severe memory deficits might be markers of clinical overlap and shared neurobiological vulnerability with psychotic disorders.