Cognitive Functioning as a Predictor of Functional Disability in Later Life

Division of Adult and Community Health, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA.
American Journal of Geriatric Psychiatry (Impact Factor: 4.24). 02/2006; 14(1):36-42. DOI: 10.1097/01.JGP.0000192502.10692.d6
Source: PubMed


The contribution of cognitive functioning on multiple levels of functional disability and mortality over two years as well as individual activities of daily living (ADLs) and instrumental activities of daily living (IADLs) tasks, in a sample of older U.S. adults was examined.
A total of 4,077 U.S. adults (1,493 males and 2,584 females) aged > or =70 years (mean = 76.35 years) from the Second Longitudinal Study of Aging (1997/1998-1999/2000) were examined using an adapted Telephone Interview of Cognitive Status (TICS), ADLs, and IADLs.
Multivariate logistic regression investigated cognition as a predictor of five mutually exclusive levels of functional disability. People with the lowest level of cognition had greater odds of mortality at follow-up (adjusted odds ratio [AOR] = 2.86, 95% confidence interval [CI] = 1.94-4.20), ADL and IADL disability (AOR = 1.58, 95% CI = 1.15-2.16), ADL disability (AOR = 1.83, 95% CI = 1.27-2.64), or IADL disability (AOR = 1.22, 95% CI = 0.86-1.71) than those who were disability-free. Cognitive functioning was not predictive of individual ADL tasks but was predictive of the IADL tasks of preparing meals, shopping for groceries, managing money, telephone use, light housework, and medications but not heavy housework.
Persons with lower levels of cognitive functioning were more likely to die or become disabled than those with higher levels of cognition. Changes in cognitive functioning might serve as an early indicator of neurologic and medical factors.

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    • "There is strong support for targeting patients with DSD at admission to post acute care as a high risk group for poor health outcomes. In these settings persistent cognitive decline is a predictor of functional dependency[25]. When delirium is unresolved, rehabilitation is hampered because the associated cognitive problems (i.e., inattention, disorientation etc) interfere with patients' ability to fully engage in restorative therapies. Our goal is to facilitate maximal rehabilitation benefits so these individuals can return to their homes. "
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    ABSTRACT: Delirium is a state of confusion characterized by an acute and fluctuating decline in cognitive functioning. Delirium is common and deadly in older adults with dementia, and is often referred to as delirium superimposed on dementia, or DSD. Interventions that treat DSD are not well-developed because the mechanisms involved in its etiology are not completely understood. We have developed a theory-based intervention for DSD that is derived from the literature on cognitive reserve and based on our prior interdisciplinary work on delirium, recreational activities, and cognitive stimulation in people with dementia. Our preliminary work indicate that use of simple, cognitively stimulating activities may help resolve delirium by helping to focus inattention, the primary neuropsychological deficit in delirium. Our primary aim in this trial is to test the efficacy of Recreational Stimulation for Elders as a Vehicle to resolve DSD (RESERVE- DSD). This randomized repeated measures clinical trial will involve participants being recruited and enrolled at the time of admission to post acute care. We will randomize 256 subjects to intervention (RESERVE-DSD) or control (usual care). Intervention subjects will receive 30-minute sessions of tailored cognitively stimulating recreational activities for up to 30 days. We hypothesize that subjects who receive RESERVE-DSD will have: decreased severity and duration of delirium; greater gains in attention, orientation, memory, abstract thinking, and executive functioning; and greater gains in physical function compared to subjects with DSD who receive usual care. We will also evaluate potential moderators of intervention efficacy (lifetime of complex mental activities and APOE status). Our secondary aim is to describe the costs associated with RESERVE-DSD. Our theory-based intervention, which uses simple, inexpensive recreational activities for delivering cognitive stimulation, is innovative because, to our knowledge it has not been tested as a treatment for DSD. This novel intervention for DSD builds on our prior delirium, recreational activity and cognitive stimulation research, and draws support from cognitive reserve theory. identifier: NCT01267682
    Trials 05/2011; 12(1):119. DOI:10.1186/1745-6215-12-119 · 1.73 Impact Factor
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    • "Declining or comparatively low cognitive function in older adults is associated with loss of independence in activities of daily living (Greiner et al. 1996; McGuire et al. 2006), nursing home admission (Gaugler et al. 2007; Joray et al. 2004), hospitalization (Chodosh et al. 2004), and mortality (Bassuk et al. 2000; Nguyen et al. 2003). The burden associated with deficits in cognitive function is expected to grow as the global population ages (Ferri et al. 2005), but few interventions to prevent, delay, or halt the progression of cognitive decline are currently available. "
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    Environmental Health Perspectives 12/2010; 119(5):682-7. DOI:10.1289/ehp.1002767 · 7.98 Impact Factor
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    • "Indeed, functional impairment, especially ADL impairment, was more common among subjects who lived with others but nearly half of the individuals with dementia living alone were found to have 2 or more impairments in IADL's. In the Canadian Study of Health and Aging over half of cognitively impaired seniors had some IADL disability (McDowell et al., 2001) and an association between cognitive impairment and functional disability has been reported by others (Scanlon et al., 2007; McGuire et al., 2006). Our findings further suggest that among individuals who are living alone with dementia, problems performing tasks which are critical to daily living may both arise and go undetected. "
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