Systematic Review and Meta-Analysis of Executive Function Following Remission From Major Depression.

BACKGROUND

Executive function is significantly impaired during an acute episode of major depressive disorder (MDD). Following remission, executive deficits recede, but whether they fully dissipate is unclear. Evidence is also mixed regarding the extent to which persisting deficits reflect decreased processing speed or a distinct executive dysfunction.

METHODS

We aimed to systematically evaluate how executive function following MDD remission compares with normal function, specify the pattern and severity of persistent deficits, examine effects of prespecified moderators, and determine if processing speed explains observed executive dysfunctions. Electronic databases and relevant reviews were systematically searched for studies published from January 1, 1972, to April 23, 2024. The main outcome was difference in test performance between patients with remitted MDD and healthy control participants. Effect sizes were calculated with random-effects models. Significant moderators of between-study variability were combined to identify the best goodness-of-fit model using multiple method of moments meta-regressions.

RESULTS

Meta-analysis of 61 variables from 244 studies (12,814 remitted patients; 10,578 healthy control participants) was performed. Significant deficits relative to controls were found in all but one speed-constrained executive tests, with effect sizes ranging from small (Hedges' g = 0.24) to large (Hedges' g = 0.86). Between-group differences became nonsignificant after controlling for processing speed. Remitted patients and controls had comparable performance on unconstrained by speed tests of executive function except for auditory and spatial working memory, where negligible (Hedges' g = 0.19) to small (Hedges' g = 0.31) deficits were observed.

CONCLUSIONS

Executive dysfunction observed in auditory working memory, set-shifting, inhibition, planning, fluency, and intellectual functioning following depression remission is largely explained by persistent impairment in processing speed.