The association of cognitive deficits with mental and physical Quality of Life in Major Depressive Disorder

Patients with Major Depressive Disorder experience significantly reduced subjective Quality of Life (QOL), including impaired social and emotional functioning and greater fatigue and physical pain. Mounting evidence suggests that cognitive dysfunction (e.g., deficits in memory, executive function) contributes independently to the onset of reduced QOL, however the domain-specific nature of this relationship has not been investigated. The present study examined the relationship between specific cognitive domains (e.g., attention, spatial cognition) and specific deficits in mental and physical QOL in subjects with lifetime MDD, as well as acutely depressed, remitted and healthy participants. Data were obtained (N = 387) from the Cognitive Function and Mood Study (COFAMS), a cross-sectional study of emotional, functional and cognitive status in individuals with mood disorders. Participants' (acutely depressed n = 93, remitted n = 170, and healthy control n = 124) QOL was assessed with the 36-Item Short Form Health Survey (SF-36) and cognitive functioning was evaluated with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), the Colorado Assessment Tests (CATs) and the Psychology Experiment Building Language (PEBL). Analyses revealed that poor immediate and delayed memory were associated with reduced mental QOL in individuals with lifetime MDD, acutely depressed, and healthy controls. In contrast, cognitive functioning was not associated with mental QOL in remitted patients. No cognitive domains were significantly related to physical QOL in any participant group. The result suggests that deficits in immediate and delayed memory may contribute to reduced mental QOL in acute MDD, whereas cognition does not appear to play a role in physical QOL. Memory should be considered important cognitive treatment targets for MDD patients suffering specifically from reduced mental QOL. •Cognitive deficits in MDD are associated with mental, but not physical, quality of life.•There is an altered role of cognitive dysfunction in mental QOL across the course of illness in MDD•Executive function is related to mental QOL in depressed participants•Immediate and delayed memory are associated with mental QOL in healthy individuals and individuals with lifetime MDD