Effects of physical activity and exercise on the cognitive function of patients with Alzheimer disease: a meta-analysis

Abstract

Background Alzheimer’s disease (AD), as the most common cause of dementia, brings huge economic burden for patients and social health care systems, which motivates researchers to study multiple protective factors, among which physical activity and exercise have been proven to be both effective and economically feasible. Methods A systematic literature search was performed for eligible studies published up to November 1st 2018 on three international databases (PubMed, Cochrane Library, and Embase) and two Chinese databases (Wanfang Data, China National Knowledge Infrastructure). All analyses were conducted using Stata 14.0. Due to heterogeneity between studies, a random-effects model was used for this meta-analysis. Meta-analysis was used to explore if physical activity and exercise can exert positive effects on cognition of elderly with AD and subgroup analyses were conducted to find out if there are dose-response effects. Results A total of 13 randomized controlled trials were included with a sample size of 673 subjects diagnosed with AD. Intervention groups showed a statistically significant improvement in cognition of included subjects measured by the MMSE score (SMD = 1.12 CI:0.66~1.59) compared to the control groups. Subgroup analyses showed different amounts of physical activity and exercise can generate different effects. Conclusions As one of few meta-analyses comparing different quantities of physical activity and exercise interventions for AD in details, our study suggests that physical activity and exercise can improve cognition of older adults with AD. While the concomitant effects on cognition functions of high frequency interventions was not greater than that of low frequency interventions, the threshold remains to be settled. However, more RCTs with rigorous study design are needed to support our findings. Electronic supplementary material The online version of this article (10.1186/s12877-019-1175-2) contains supplementary material, which is available to authorized users.

Astrocyte remodeling in the beneficial effects of long-term voluntary exercise in Alzheimer’s disease

“…In line with a previous study [ 38 ], our results demonstrated that 6 months of wheel running significantly reduced exploratory activity of 5xFAD and WT mice in terms of total distance traversed. In addition to non-cognitive testing, the results of this study showed exercise-induced improvements in hippocampal-dependent learning and memory, as has been previously shown in various mouse AD studies [ 17 , 35 , 41 , 42 ] and in patients with AD [ 43 ]. Based on previous literature, it is possible that voluntary physical exercise may stabilize AD-related behavioral impairments of structural changes in the hippocampus, regulation of the neurotransmitter system, or the expression of growth factors that regulate neurogenesis, synaptic plasticity, and inflammation [ 4 , 44 ].…”

Satisfaction with Life, Subjective Well-Being and Functional Skills in Active Older Adults Based on Their Level of Physical Activity Practice

“…It is necessary to point out that most studies in the area of old age have focused on cognitive impairment [42,43], strength and agility [44], or on the pathological perspective of old age (e.g., Alzheimer's) [45]. Hence, there are few scientific studies at present that have focused on the positive promotion of health as well as other profiles without pathologies.…”

Association between physical activity and conversion from mild cognitive impairment to dementia

“…In a recent meta-analysis, physical activity of more than 16 weeks was associated with a greater improvement in cognition. [10] In addition, the incidence rate of dementia was lower in subjects who engaged in physical activity more than twice per week. [11,12] However, the association between withdrawal or initiation of physical activity and prevention against cognitive decline remains poorly understood.…”