Longitudinal Changes in Memory and Executive Functioning are Associated with longitudinal change in instrumental activities of daily living in older Adults

Abstract

Impaired everyday function is a diagnostic criterion for dementia, and a determinant of healthcare utilization and caregiver burden. Although many previous studies have demonstrated a crosssectional relationships between cognition (particularly executive functions and memory) and everyday function in older adults, very little is known about longitudinal relationships between these domains. This study examined the association between longitudinal change in episodic memory (MEM) and executive functioning (EXEC) and change in everyday function. Participants were a cognitively heterogeneous group of 100 elderly persons including those with normal cognition, as well as those with mild cognitive impairment and dementia. They were followed for an average of five years. Random effects modeling showed that change in both MEM and EXEC were independently associated with rate of change in informant-rated instrumental activities of daily living (IADLs), even after controlling for age, education, and gender. Findings indicate that declines in MEM and EXEC over time make unique and independent contributions to declines in older adults' ability to function in daily life. KeywordsMemory; Executive functioning; Everyday Function; dementia; Alzheimer's disease Mild Cognitive Impairment (MCI) and dementias such as Alzheimer's disease (AD) become increasingly common with age. They are both associated with problems in everyday function that result in patient and caregiver distress, reduced quality of life, increased use of healthcare services, and nursing home placement (Hope, Keene, Gedling, Fairburn, & Jacob, 1998;Vetter et al., 1999). Given its associated burden, an improved understanding of the determinants of functional decline, including the nature of the relationship between the development of specific cognitive impairments and the development of functional impairments is paramount. The assessment of everyday functioning in older adults typically focuses on an individual's ability to carry out activities of daily living (ADLs) because it is these activities that are critical to independent living. Basic ADLs (BADLs) include tasks such as grooming, feeding, and toileting, while instrumental ADLs (IADLs) involve complex behaviors including managing finances, handling medications, and housekeeping. BADLs are highly correlated with motor functioning and coordination (Bennett et al., 2002;Boyle, Cohen, Paul, Moser, & Gordon, 2002;Cahn & Sullican, 1998). In contrast, declines in IADLs have been shown to be more influenced by cognitive functioning, are affected relatively early in the course of dementia (Stern, Hesdorffer, Sano, & Mayeuz, 1990), and can even be present in preclinical dementia states such as mild cognitive impairment (MCI) (Griffith et al., 2003;Ritchie, Artero, & Touchon, 2001).Previous studies have demonstrated cross-sectional relationships between neuropsychological performance and everyday function in older adult populations. Among these studies, the cognitive domains most consistently found to be associat...

Functional Disability Profiles in Amnestic Mild Cognitive Impairment

“…Previous studies have demonstrated the importance of executive function in the performance of IADL [16,31,32]. In our study, TMT-B was correlated with IADL and the 3 executive subscales.…”

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Malperformance in Verbal Fluency and Delayed Recall as Cognitive Risk Factors for Impairment in Instrumental Activities of Daily Living

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Multi-domain training enhances attentional control.

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