Article

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: 8.29). 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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Available from: Jeffrey M Burns, Apr 09, 2014
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    • "Previous work from our lab suggests that effects of aerobic fitness and serum BDNF interact to support episodic recognition memory (Whiteman et al., 2014) in a task we have shown to recruit the hippocampus and perirhinal/EC (Schon et al., 2004, 2005). Additionally , increased cardio-respiratory fitness is associated with greater volume of the parahippocampal gyrus in Alzheimer's disease patients (Honea et al., 2009), and aerobic exercise consistently appears as one of the most effective interventions to attenuate cognitive decline in geriatric populations (Barnes & Yaffe, 2011; Burns et al., 2008). In younger cohorts, exercise-induced gains in cardio-respiratory fitness have been linked to better relational memory in children (Chaddock et al., 2010), and better learning of a virtual Morris Water Maze task in adolescents (Herting and Nagel, 2012). "
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    Full-text · Article · Nov 2015 · NeuroImage
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    • "All studies employed a cross-sectional MRI design. Although three studies did not report a significant association (Bugg and Head, 2011; Burns et al., 2008; Tseng et al., 2013b), higher levels of PA were associated with greater global WM volumes in the two largest studies (Benedict et al., 2013; Gow et al., 2012). A meta-analysis of all five studies showed an overall small mean effect size of 0.22 (95% confidence interval (CI) = 0.10 to 0.34, p b 0.001) (Fig. 1). "
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    Preview · Article · Oct 2015 · NeuroImage
    • "The PASE has previously been validated against physiological measures of physical activity including accelerometer (Washburn & Ficker, 1999), mini-logger (Harada et al., 2001), peak oxygen uptake and balance score (). The questionnaire is validated for completion by carers of dementia patients (Burns et al., 2008Burns et al., , 2010Honea et al., 2009). Cognitive activities were measured using the Florida Cognitive Activities Scale (FCAS;Schinka et al., 2005). "
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