Physical activity and mild cognitive impairment and Alzheimer's disease.

Academic Unit for Psychiatry of Old Age, St. Vincent's Health, Department of Psychiatry, St. George's Hospital, The University of Melbourne, 283 Cotham Road, Kew, 3103, Victoria, Australia.
Current Neurology and Neuroscience Reports (Impact Factor: 3.78). 09/2010; 10(5):352-8. DOI: 10.1007/s11910-010-0121-7
Source: PubMed

ABSTRACT Regular physical activity undoubtedly has many health benefits for all age groups. In the past decade, researchers and clinicians have begun to focus their attention on whether physical activity also can improve health outcomes of older adults who experience mild cognitive impairment (MCI) or dementia. This ongoing question is gaining relevance in light of the aging of the world population and with it the rise of age-related conditions, such as cognitive impairment. Not surprisingly, physical activity is among the potential protective lifestyle factors mentioned when strategies to delay or prevent dementia are discussed. The first large-scale multidomain intervention trials are under way to put this to the test. This review aims to give an overview of recent trials of physical activity in patients with MCI or dementia.

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    ABSTRACT: Numerous studies have shown that physical exercise has positive effects on cognition in healthy adults. Less is known about the effectiveness of exercise interventions in older individuals already suffering from mild cognitive impairment (MCI) or dementia. The aim of this study was to systematically review the evidence from randomized controlled trials (RCTs) of the effects of physical exercise on cognition in older subjects with MCI or dementia. PubMed, Cochrane and DARE databases were systematically searched for RCTs using terms related to cognition and physical exercise. Altogether, 22 trials were found. The studies on older subjects with MCI reported some positive effects of physical exercise on cognition, mainly on global cognition, executive function, attention and delayed recall. However, most studies performed on older subjects with dementia showed no effect of exercise on cognition. The studies had methodological problems in defining dementia/MCI diagnosis, blinding, inadequate sample sizes and not reporting dropouts, compliance or complications. More studies of good quality on older adults with dementia are needed. © 2014 S. Karger AG, Basel.
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    ABSTRACT: Background: Findings from the literature vary in relation to whether physical activity brings about less cognitive decline in old age. The present study investigated self-reported levels of physical activity in old age and its association with the risk of dementia-related mortality. Methods: We included data from 31,086 subjects, between 65 and 80 years old, from the CONOR (Cohort of Norway) database. Cox regression analysis was used to estimate the risk of association. Results: Taking part in ‘light' (not causing perspiration or panting) activities of <3 h per week was associated with a decreased risk of dementia-related mortality, with a hazard ratio (HR) of 0.74 and a 95% confidence interval (CI) of 0.62-0.88, and of >3 h per week, with an HR of 0.61 and a 95% CI of 0.51-0.73. When taking part in ‘hard' (causing perspiration or panting) activities, a similar risk (HR = 0.56; 95% CI 0.43-0.72) was observed for >3 h per week. Interestingly, the highest reduction in risk was seen for ‘hard' activities of <3 h per week (HR = 0.50; 95% CI 0.41-0.61). Conclusion: Physical activity during leisure time in old age was associated with a lower risk of dementia-related mortality when compared to inactive individuals.
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