Role of Executive Dysfunction and Dysexecutive Behavior in Late-Life Depression and Disability

Both executive dysfunction (ED), measured by performance-based tasks, and dysexecutive behavior (DB), measured by behavioral rating scales, contribute to late-life depression and comorbid disability. There is a modest positive association of ED and DB, but less is known about their relative contributions to core aspects of neuropsychiatric conditions and whether they provide unique or redundant information.

Latent variable analyses were applied to ED, DB, depression, and disability data from 220 older patients with major depression and ED who had been enrolled in a psychosocial treatment study of depression. ED measures included the Trail Making Test, part B, Stroop Color Word Interference Test, and Hopkins Verbal Learning Test-Trail 1. The ED scale from the Frontal Systems Behavior Scale, self and other-rated, served as the ratings-based measure of DB.

The measurement model, with all four latent variables related to one another, demonstrated good fit (RMSEA=0.06). In the structural models, DB was associated with both depression (β=0.61) and disability (β=0.42), whereas ED was associated with depression (β=0.43) but not disability (β=0.16). Social problem-solving accounted for 49% of the influence of DB on late-life depression, whereas ED was not related to social problem-solving.

ED and the lesser studied DB measures offer unique and complementary information. DB was robustly associated with late-life depression and disability. Patients with depression and ED may be more likely to develop disability when they exhibit DB and social problem-solving difficulties.