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Background: Alzheimer's disease, a global public health issue, accounts for 60 to 80% of all dementias. Alzheimer's disease primarily causes cognitive impairment and drugs have only modest short-term effects, highlighting a pressing need to develop effective interventions. Aerobic exercise holds promise for treating cognitive impairment in Alzheimer's disease through biologically sound mechanisms. Nonetheless, aerobic exercise studies in Alzheimer's disease are limited with mixed findings., Methods/design: This pilot randomized controlled trial will investigate the effects of a 6-month, individualized, moderate-intensity cycling intervention (20 to 50 minutes per session, 3 times a week) on cognition and hippocampal volume in community-dwelling older adults with mild-to-moderate Alzheimer's disease. The specific aims are to: 1) determine the immediate effect of the cycling intervention on cognition in Alzheimer's disease; 2) examine if the cycling intervention slows cognitive decline in Alzheimer's disease from baseline to 12 months; and 3) assess the effect of aerobic exercise on hippocampal volume over 12 months. Ninety subjects will be randomized on a 2:1 allocation ratio to cycling or attention control (low-intensity stretching) and followed for another 6 months. Allocations will be concealed to all investigators and outcome assessors will be blinded to group assignments and previous data. Cognition will be measured by the Alzheimer's disease Assessment Scale-Cognition at baseline before randomization and at 3, 6, 9, and 12 months. Hippocampal volume will be measured by magnetic resonance imaging at baseline and 6 and 12 months. The sample size of 90 will give 80% power to detect a 2.5-point difference in within-group changes in the Alzheimer's disease Assessment Scale-Cognition at 6 months for the cycling group., Discussion: Findings from this study will address the critical gap of exercise efficacy in Alzheimer's disease and use of magnetic resonance imaging as an outcome measure in clinical trials. This study will provide a potential treatment that may increase physical function and quality of life and curb the prohibitive costs for the growing dementia population., Trial Registration: Primary registration: (NCT01954550; date of registration: 20 September 2013). Secondary registration: (NCT01954550; date of registration: 1 October 2013).

Aerobic exercise is a promising behavioral therapy for Alzheimer's disease (AD), yet few studies have investigated the effect of aerobic exercise on cognition in AD. The purpose of this pilot study was to examine the effect of 6-month aerobic exercise on the change in executive function, global cognition, quality of life (QOL), and depression in community-dwelling older adults with mild to moderate AD. A single group, repeated measures design with outcomes measured at baseline, 3 months, and 6 months was used. Results show that there were no significant changes in any measures except for depression (p = .026). There was a trend toward improvement in executive function and QOL with moderate effect sizes (ESs) and a trend toward deterioration in global cognition with moderate to large ESs. Randomized controlled trials are needed to evaluate the therapeutic effect of aerobic exercise in older adults with AD.

Objectives: To examine the effects of vitamin D and calcium on cognitive outcomes in elderly women., Design: Post hoc analysis of a randomized double-blind placebo-controlled trial., Setting: Forty Women's Health Initiative (WHI) clinical centers across the United States., Participants: Four thousand one hundred forty-three women aged 65 and older without probable dementia at baseline who participated in the WHI Calcium and Vitamin D Trial and the WHI Memory Study., Intervention: Two thousand thirty-four women were randomized to receive 1,000 mg of calcium carbonate combined with 400 IU of vitamin D(3) (treatment) and 2,109 to placebo., Measurements: Primary: classifications of probable dementia or mild cognitive impairment (MCI) based on a four-phase protocol that included central adjudication. Secondary: global cognitive function and individual cognitive subtests., Results: Mean age of participants was 71. During a mean follow-up of 7.8 years, 39 participants in the treatment group and 37 in the placebo group developed incident dementia (hazard ratio (HR) = 1.11, 95% confidence interval (CI) = 0.71-1.74, P = .64). Likewise, 98 treatment participants and 108 placebo participants developed incident MCI (HR = 0.95, 95% CI = 0.72-1.25, P = .72). There were no significant differences in incident dementia or MCI or in global or domain-specific cognitive function between groups., Conclusion: There was no association between treatment assignment and incident cognitive impairment. Further studies are needed to investigate the effects of vitamin D and calcium separately, on men, in other age and ethnic groups, and with other doses., (© 2012, Copyright the Authors Journal compilation © 2012, The American Geriatrics Society.)

Background: Aerobic exercise has shown inconsistent cognitive effects in older adults with Alzheimer's disease (AD) dementia.Objective: To examine the immediate and longitudinal effects of 6-month cycling on cognition in older adults with AD dementia.Methods: This randomized controlled trial randomized 96 participants (64 to cycling and 32 to stretching for six months) and followed them for another six months. The intervention was supervised, moderate-intensity cycling for 20-50 minutes, 3 times a week for six months. The control was light-intensity stretching. Cognition was assessed at baseline, 3, 6, 9, and 12 months using the AD Assessment Scale-Cognition (ADAS-Cog). Discrete cognitive domains were measured using the AD Uniform Data Set battery.Results: The participants were 77.4±6.8 years old with 15.6±2.9 years of education, and 55% were male. The 6-month change in ADAS-Cog was 1.0±4.6 (cycling) and 0.1±4.1 (stretching), which were both significantly less than the natural 3.2±6.3-point increase observed naturally with disease progression. The 12-month change was 2.4±5.2 (cycling) and 2.2±5.7 (control). ADAS-Cog did not differ between groups at 6 (p = 0.386) and 12 months (p = 0.856). There were no differences in the 12-month rate of change in ADAS-Cog (0.192 versus 0.197, p = 0.967), memory (-0.012 versus -0.019, p = 0.373), executive function (-0.020 versus -0.012, p = 0.383), attention (-0.035 versus -0.033, p = 0.908), or language (-0.028 versus -0.026, p = 0.756).Conclusion: Exercise may reduce decline in global cognition in older adults with mild-to-moderate AD dementia. Aerobic exercise did not show superior cognitive effects to stretching in our pilot trial, possibly due to the lack of power. [ABSTRACT FROM AUTHOR]

Little is known about how aerobic exercise affects Alzheimer’s disease (AD). The purpose of this pilot study was to test the impact of 6-month cycling on AD symptoms in community-dwelling older adults with mild-to-moderate AD, using a single-group, repeated-measures design (n = 26). AD symptoms were measured with the AD Assessment Scale–Cognitive (ADAS-Cog), Disability in AD (DAD), and Neuropsychiatric Inventory–Caregiver (NPI-Q) scales at baseline, 3 and 6 months. Data were analyzed using mixed linear models. The ADAS-Cog, DAD, and NPI-Q severity scores remained unchanged over the 6-month period, while caregiver distress decreased 40% (p < .05). We conclude that aerobic exercise may reduce AD symptoms and appears effective in decreasing caregiver distress. Further randomized controlled trials are needed to examine the effects of aerobic exercise in AD. [ABSTRACT FROM PUBLISHER]