Association between depression severity and executive functioning in late-life depression: a systematic review

Abstract

OBJECTIVE: Late-life depression is an under-diagnosed and under-treated disease that reduces the well-being of older adults. Executive dysfunction is another critical impairment in elderly depressed individuals which further disrupts their everyday functioning. This systematic review aims to analyze the association between executive function and depression severity in elderly individuals diagnosed with major depressive disorder. METHOD:The studies were retrieved from MEDLINE/PubMed, ISI Web of Knowledge and PsychInfo, after a search strategy combining the terms "depression", "executive function", "neuropsychological assessment", "elderly" and "late life". Study selection, data collection and quality ratings was performed by two independent raters. RESULTS: A total of 1,130 articles were found but only 8 studies met the defined eligibility criteria and evaluated the association between depression severity and executive functioning. Six out of 8 studies found an association between depression severity and executive function, with correlations ranging from small to large (r= -0.15 to -0.53). The included reports had several methodological limitations such as selective data reporting, non-comprehensive executive function assessment and not controlling potential biases. CONCLUSION: Depression severity may be more strongly correlated with a specific set of executive abilities although it also seems to be a broad-based association with executive functioning as a whole. Future high-quality prospective studies are recommended in order to understand the causal relationship between depression severity and executive functioning taking into account possible mediators such as age-related or neurodegenerative cognitive impairment, educational level and other clinic characteristics (e.g. age of onset, medication).

Differential and spatial expression meta-analysis of genes identified in genome-wide association studies of depression

“…Dysfunction in prefrontal cortical circuits is commonly implicated in depression pathogenesis 15,18,[41][42][43] . Furthermore, these regions primarily play a role in executive functions and emotion regulation, which are often impaired in depression [33][34][35][36][37][38]44,45 . Prior focus on the frontal cortex may have indirectly inflated its relevance to the disorder.…”

“…Cortical structures are common targets of depression research, and expression patterns across the cerebral cortex are more consistent than subcortical tissues 26,[33][34][35][36][37][38] . Therefore, we restricted our analysis to cortical brain regions in both sexes by combining 18 region and sexspecific analyses.…”

Differential and spatial expression meta-analysis of genes identified in genome-wide association studies of depression

“…Dysfunction in prefrontal cortical circuits is commonly implicated in depression pathogenesis 15,18,[41][42][43] . Furthermore, these regions primarily play a role in executive functions and emotion regulation, which are often impaired in depression [33][34][35][36][37][38]44,45 . Prior focus on the frontal cortex may have indirectly inflated its relevance with the disease.…”

“…Cortical structures are common targets of depression research, and expression patterns across the cerebral cortex are more consistent than subcortical tissues 26,[33][34][35][36][37][38] . Therefore, we restricted our analysis to cortical brain regions in both sexes by combining 18 region and sex-specific analyses.…”

Crosstalk between Depression and Dementia with Resting-State fMRI Studies and Its Relationship with Cognitive Functioning

“…Cognitive impairments in individuals with depression have been consistently reported in meta-analyses and reviews [ 31 , 32 , 33 , 34 ]. Based on these results, difficulties with concentration and making decisions have been described as part of major depressive disorder (MDD) [ 1 ].…”