A Reanalysis of Cognitive-Functional Performance in Older Adults: Investigating the Interaction Between Normal Aging, Mild Cognitive Impairment, Mild Alzheimer's Disease Dementia, and Depression

Abstract

Depressive symptoms are associated with cognitive-functional impairment in normal aging older adults (NA). However, less is known about this effect on people with mild Cognitive Impairment (MCI) and mild Alzheimer's disease dementia (AD). We investigated this relationship along with the NA-MCI-AD continuum by reanalyzing a previously published dataset. Participants (N = 274) underwent comprehensive neuropsychological assessment including measures of Executive Function, Language/Semantic Memory, Episodic Memory, Visuospatial Abilities, Activities of Daily Living (ADL), and the Geriatric Depression Scale. MANOVA, logistic regression and chi-square tests were performed to assess the association between depression and cognitive-functional performance in each group. In the NA group, depressed participants had a lower performance compared to non-depressed participants in all cognitive and functional domains. However, the same pattern was not observed in the MCI group or in AD. The results suggest a progressive loss of association between depression and worse cognitive-functional performance along the NA-MCI-AD continuum.

Mild cognitive impairment, psychiatric symptoms, and executive functioning in patients with Parkinson's disease

“…Due to these compromised resources, individuals with PD‐MCI may be more acutely vulnerable to the negative effects of anxiety, depression, and apathy on cognitive performance. Conversely, mood symptoms may only have a minimal association with cognitive performance in PD‐MCI patients as the accumulated neurodegenerative changes in seen in MCI may reduce depression‐related neurobiological changes on cognitive performance, as was found in a study in a non‐PD sample of cognitively healthy older adults, older adults with MCI, and patients with AD . Elucidating the moderating role of PD‐MCI is important as this may increase our understanding of the complex associations between psychiatric symptoms and cognitive performance and potentially aid in identifying temporal windows for when interventions may be most impactful.…”

On the conundrum of cognitive impairment due to depressive disorder in older patients

“…Thus, characterization of the pattern of cognitive deficits is sufficient to delineate the profile of cognitive impairment due to DD in younger subjects. Studies in older persons often assume the same procedure and diagnose the cause of cognitive impairment on clinical and neuropsychological grounds [4][5][6] despite other studies reporting that distinction between cognitive impairment due to DD and cognitive impairment due to AD is difficult if not impossible on clinical and neuropsychological grounds [7,8].…”

Cognitive deficits in older adults with mild cognitive impairment in a two-year follow-up study

“…After 6 months of treatment with medical experts, 61.5% showed improvement in depression symptoms and persistent cognitive impairment in 44.2% of the sample. In a study by De-Paula et al, 27 274 healthy elderly adults with MCI and dementia were evaluated to investigate the association between depression and cognitive and functional performance in each group. In the group of non-demented older adults, depressed participants performed worse than non-depressed participants on the cognitive tests, with a greater effect being observed in executive function tests.…”