Research paperResidual depressive symptoms, sleep disturbance and perceived cognitive impairment as determinants of functioning in patients with bipolar disorder

- Residual symptoms have an impact on functioning in euthymic bipolar patients.
- Residual depressive symptoms and cognitive performance directly affect functioning.
- Sleep disturbances were indirectly associated with functioning.
- Residual symptoms should be targeted in personalized treatment plans.

BackgroundMany patients with bipolar disorder (BD) experience residual symptoms during their inter-episodic periods. The study aimed to analyse the relationship between residual depressive symptoms, sleep disturbances and self-reported cognitive impairment as determinants of psychosocial functioning in a large sample of euthymic BD patients.MethodsThis was a cross-sectional study of 468 euthymic BD outpatients. We evaluated the residual depressive symptoms with the Bipolar Depression Rating Scale, the sleep disturbances with the Pittsburgh Sleep Quality Index, the perceived cognitive performance using visual analogic scales and functioning with the Functioning Assessment Short Test. Structural equation modelling (SEM) was used to describe the relationships among the residual depressive symptoms, sleep disturbances, perceived cognitive performance and functioning.ResultsSEM showed good fit with normed chi square=2.46, comparative fit index=0.94, root mean square error of approximation=0.05 and standardized root mean square residuals=0.06. This model revealed that residual depressive symptoms (path coefficient =0.37) and perceived cognitive performance (path coefficient=0.27) were the most important features significantly related to psychosocial functioning. Sleep disturbances were indirectly associated with functioning via residual depressive symptoms and perceived cognitive performance (path coefficient=0.23).ConclusionsThis study contributes to a better understanding of the determinants of psychosocial functioning during the inter-episodic periods of BD patients. These findings should facilitate decision-making in therapeutics to improve the functional outcomes of BD during this period.