Cardiorespiratory fitness and brain atrophy in early Alzheimer disease.

Department of Neurology, Hoglund Brain Imaging Center, University of Kansas School of Medicine, 3599 Rainbow Blvd, MSN 2012, Kansas City, KS 66160, USA.
Neurology (Impact Factor: 8.3). 08/2008; 71(3):210-6. DOI: 10.1212/01.wnl.0000317094.86209.cb
Source: PubMed

ABSTRACT To examine the correlation of cardiorespiratory fitness with brain atrophy and cognition in early-stage Alzheimer disease (AD).
In normal aging physical fitness appears to mitigate functional and structural age-related brain changes. Whether this is observed in AD is not known.
Subjects without dementia (n = 64) and subjects with early-stage AD (n = 57) had MRI and standard clinical and psychometric evaluations. Peak oxygen consumption (VO(2)(peak)), the standard measure of cardiorespiratory fitness, was assessed during a graded treadmill test. Normalized whole brain volume, a brain atrophy estimate, was determined by MRI. Pearson correlation and linear regression were used to assess fitness in relation to brain volume and cognitive performance.
Cardiorespiratory fitness (VO(2)(peak)) was modestly reduced in subjects with AD (34.7 [5.0] mL/kg/min) vs subjects without dementia (38.1 [6.3] mL/kg/min, p = 0.002). In early AD, VO(2)(peak) was associated with whole brain volume (beta = 0.35, p = 0.02) and white matter volume (beta = 0.35, p = 0.04) after controlling for age. Controlling for additional covariates of sex, dementia severity, physical activity, and physical frailty did not attenuate the relationships. VO(2)(peak) was associated with performance on delayed memory and digit symbol in early AD but not after controlling for age. In participants with no dementia, there was no relationship between fitness and brain atrophy. Fitness in participants with no dementia was associated with better global cognitive performance (r = 0.30, p = 0.02) and performance on Trailmaking A and B, Stroop, and delayed logical memory but not after controlling for age.
Increased cardiorespiratory fitness is associated with reduced brain atrophy in Alzheimer disease (AD). Cardiorespiratory fitness may moderate AD-related brain atrophy or a common underlying AD-related process may impact both brain atrophy and cardiorespiratory fitness.

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    ABSTRACT: Aims This article summarizes the literature on some of the biological mechanisms involved in Alzheimer disease and their evolution in the context of non-pharmacological interventions. Actuality Regular aerobic physical activity and enriched environment are two methods derived from the metabolic hypothesis and the cognitive enrichment hypothesis respectively. Their effects on aerobic fitness, cardiorespiratory function, brain structure and cognition are clearly established in the aging process in humans and animals. In the field of Alzheimer's disease, these methods might halt mitochondrial, amyloidogenic and tau pathophysiological development. Perspectives In elderly patients, the use of exergames (active video games) develops in order to make physicals activities more attractive. These new technologies, with high potential, would propose simultaneously aerobic activity in an enriched environment. Intervention research on the feasibility and the effects of these exergames for Alzheimer patients may be a way forward. Conclusion We propose to use serious (exer)games to stimulate Alzheimer patients. These serious games, being specifically developed for Alzheimer patients, would be to integrate high intensity aerobic activity and enriched environment into a ludic and accessible therapy.
    Science & Sports 12/2014; · 0.54 Impact Factor

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