A longitudinal study of cognition, functional outcome and quality of life in bipolar disorder and major depression.

Objective: Cognitive impairments are known to be a frequent cause of disability in bipolar disorder (BD) and major depression (MDD). Yet there is no consensus regarding the particular cognitive functions whose impairments can lead to disability in each domain of functioning. The aim of this study was to perform a longitudinal evaluation of working memory, inhibition, cognitive flexibility and attention in BD and MDD, investigate the relationship of these cognitive functions to disability and quality of life, and evaluate the impact of variables related to cognitive reserve (education and daily cognitive stimulation) on cognitive performance.

Method: 31 participants (MDD = 12; BD = 19) were evaluated at baseline and after an average time of 2 years.

Results: the BD group showed improvements in attention while patients with MDD improved on measures of attention and working memory. In BD working memory performance was associated with the cognition and mobility domains of functioning, and with physical and environmental quality of life. In MDD, cognitive flexibility was related to social relationships and environmental quality of life.

Conclusion: working memory and cognitive flexibility may be an interesting target for interventions aiming to improve everyday functioning and quality of life in BD and MDD.