Effectiveness of physical exercise at improving functional capacity in older adults living with Alzheimer's disease: a systematic review of randomized controlled trials

Different physical exercise in the treatment of Alzheimer's disease

Alzheimer's disease (AD) is rapidly becoming one of the most expensive, burdening, and deadly diseases of this century. Up to now, there is still a lack of pharmacotherapy with substantial efficacy, and physical exercise is a promising and low-cost way to aid in delaying the process of AD. The aim of this review is to summarise the efficacy of different physical exercise approaches and doses in the management of AD, including aerobic exercise, resistance exercise and multicomponent exercise. A literature search using MeSH terms for each topic is undertaken using PubMed and the Web of Science Core Collection database, supplemented by hand searching for additional references. Retrieved articles were reviewed, synthesised, and summarised. This review shows that aerobic exercise has been almost unanimously recognised for the improvement of cognition, neuropsychiatric symptoms and activities of daily living. Resistance exercise also shows a good prospect in the above aspects and has a unique advantage in enhancing muscle strength, while multicomponent physical activity does not seen to significantly improve cognitive function. Each type of exercise has a dose effect, but for individuals with AD, the most appropriate exercise dose is still controversial.

From Plaques to Pathways in Alzheimer's Disease: The Mitochondrial-Neurovascular-Metabolic Hypothesis

Alzheimer's disease (AD) presents a public health challenge due to its progressive neurodegeneration, cognitive decline, and memory loss. The amyloid cascade hypothesis, which postulates that the accumulation of amyloid-beta (Aβ) peptides initiates a cascade leading to AD, has dominated research and therapeutic strategies. The failure of recent Aβ-targeted therapies to yield conclusive benefits necessitates further exploration of AD pathology. This review proposes the Mitochondrial-Neurovascular-Metabolic (MNM) hypothesis, which integrates mitochondrial dysfunction, impaired neurovascular regulation, and systemic metabolic disturbances as interrelated contributors to AD pathogenesis. Mitochondrial dysfunction, a hallmark of AD, leads to oxidative stress and bioenergetic failure. Concurrently, the breakdown of the blood-brain barrier (BBB) and impaired cerebral blood flow, which characterize neurovascular dysregulation, accelerate neurodegeneration. Metabolic disturbances such as glucose hypometabolism and insulin resistance further impair neuronal function and survival. This hypothesis highlights the interconnectedness of these pathways and suggests that therapeutic strategies targeting mitochondrial health, neurovascular integrity, and metabolic regulation may offer more effective interventions. The MNM hypothesis addresses these multifaceted aspects of AD, providing a comprehensive framework for understanding disease progression and developing novel therapeutic approaches. This approach paves the way for developing innovative therapeutic strategies that could significantly improve outcomes for millions affected worldwide.

Resistance Exercise Training as a New Trend in Alzheimer's Disease Research: From Molecular Mechanisms to Prevention

Alzheimer's disease is a pathology characterized by the progressive loss of neuronal connections, which leads to gray matter atrophy in the brain. Alzheimer's disease is the most prevalent type of dementia and has been classified into two types, early onset, which has been associated with genetic factors, and late onset, which has been associated with environmental factors. One of the greatest challenges regarding Alzheimer's disease is the high economic cost involved, which is why the number of studies aimed at prevention and treatment have increased. One possible approach is the use of resistance exercise training, given that it has been shown to have neuroprotective effects associated with Alzheimer's disease, such as increasing cortical and hippocampal volume, improving neuroplasticity, and promoting cognitive function throughout the life cycle. However, how resistance exercise training specifically prevents or ameliorates Alzheimer's disease has not been fully characterized. Therefore, the aim of this review was to identify the molecular basis by which resistance exercise training could prevent or treat Alzheimer's disease.

Effect of aquatic exercise programs according to the International Classification of Functionality, Disability and Health domains in individuals with Parkinson's disease: a systematic review and meta-analysis with GRADE quality assessment

PURPOSE

To investigate the effects of aquatic exercise programs (AEP) in body structure and function, activity, and participation outcomes in individuals with Parkinson's disease (PD) with mild to moderate disability levels.

METHODS

Six databases were searched from inception until November 2022. Randomized clinical trials that used AEP alone, AEP combined and/or compared two types of AEP were included. The quality of evidence was assessed by the GRADE approach and the standardized mean differences (SMD) were calculated the meta-analysis.

RESULTS

Twelve studies (n = 380) were included. AEP alone was superior to active control in improving body structure and function outcome: postural balance (low evidence, SMD = 0.47, p = 0.02). No statistically significant differences were found for the other body structure and function outcomes: lower limb muscle strength (p = 0.14) and depressive symptoms (p = 0.79), activity outcomes: mobility (p = 0.32) and participation outcomes: quality of life (p = 0.05). AEP combined showed no statistically significant difference for the outcomes of body structure and function: postural balance (p = 0.11) and activity: mobility (p = 0.21) when compared to active control.

CONCLUSION

AEP showed positive effects on body structure and function outcome (postural balance) in individuals with PD with mild to moderate disability levels while, no significant improvements were noticed for activity and participation outcomes.IMPLICATIONS FOR REHABILITATIONOur findings indicate that aquatic exercise programs (AEP) lead to significant improvements on body structure and function (i.e., postural balance) in individuals with Parkinson's disease (PD).The AEP evaluated in this study implemented postural balance, gait, single and double training, as well as aerobic exercises, trunk mobility exercises, and Ai Chi.The average duration, frequency, and total time implemented were 50 minutes, three times a week, for seven weeks, respectively.Considering the potential benefits identified in this study, AEP can be recommended as an adjunct treatment strategy for individuals with PD.Additionally, the use of the International Classification of Functionality, Disability and Health on the development of rehabilitation treatment plans is advised.

Adapted Home-Based Exercises in Dementia: An Exploratory Pre-post Pilot and Feasibility Study

The goals of this exploratory pre-post pilot and feasibility study (NCT04916964) were to assess the feasibility and effectiveness of an adapted Test-and-Exercise home-based exercise program on basic functional mobility and executive functions in persons with prodromal or mild Alzheimer's disease. Participants followed an 8 week exercise program at home, once per week with a physiotherapist and twice per week with their usual caregiver or independently. Functional mobility and executive functions were assessed before and after the intervention. Feasibility criteria were recruitment opportunity, participation agreement rate, cost adequacy, and drop-out rate. Twelve participants aged 80.83 ± 4.65 years took part in the study. All the basic functional mobility measures showed small effect sizes. Concerning executive functions, 5 measures showed small to moderate effect sizes. The 4 feasibility criteria were met. A larger scale study would, however, need adaptations and prior research on the ability of this population to use touch-screen technology.

Exercise Intervention for Alzheimer's Disease: Unraveling Neurobiological Mechanisms and Assessing Effects

Alzheimer's disease (AD) is a progressive neurodegenerative disease and a major cause of age-related dementia, characterized by cognitive dysfunction and memory impairment. The underlying causes include the accumulation of beta-amyloid protein (Aβ) in the brain, abnormal phosphorylation, and aggregation of tau protein within nerve cells, as well as neuronal damage and death. Currently, there is no cure for AD with drug therapy. Non-pharmacological interventions such as exercise have been widely used to treat AD, but the specific molecular and biological mechanisms are not well understood. In this narrative review, we integrate the biology of AD and summarize the knowledge of the molecular, neural, and physiological mechanisms underlying exercise-induced improvements in AD progression. We discuss various exercise interventions used in AD and show that exercise directly or indirectly affects the brain by regulating crosstalk mechanisms between peripheral organs and the brain, including "bone-brain crosstalk", "muscle-brain crosstalk", and "gut-brain crosstalk". We also summarize the potential role of artificial intelligence and neuroimaging technologies in exercise interventions for AD. We emphasize that moderate-intensity, regular, long-term exercise may improve the progression of Alzheimer's disease through various molecular and biological pathways, with multimodal exercise providing greater benefits. Through in-depth exploration of the molecular and biological mechanisms and effects of exercise interventions in improving AD progression, this review aims to contribute to the existing knowledge base and provide insights into new therapeutic strategies for managing AD.

Topical Cellular/Tissue and Molecular Aspects Regarding Nonpharmacological Interventions in Alzheimer's Disease-A Systematic Review

One of the most complex and challenging developments at the beginning of the third millennium is the alarming increase in demographic aging, mainly-but not exclusively-affecting developed countries. This reality results in one of the harsh medical, social, and economic consequences: the continuously increasing number of people with dementia, including Alzheimer's disease (AD), which accounts for up to 80% of all such types of pathology. Its large and progressive disabling potential, which eventually leads to death, therefore represents an important public health matter, especially because there is no known cure for this disease. Consequently, periodic reappraisals of different therapeutic possibilities are necessary. For this purpose, we conducted this systematic literature review investigating nonpharmacological interventions for AD, including their currently known cellular and molecular action bases. This endeavor was based on the PRISMA method, by which we selected 116 eligible articles published during the last year. Because of the unfortunate lack of effective treatments for AD, it is necessary to enhance efforts toward identifying and improving various therapeutic and rehabilitative approaches, as well as related prophylactic measures.

Italian guidance on Dementia Day Care Centres: A position paper

Dementia Day Care Centres (DDCCs) are defined as services providing care and rehabilitation to people with dementia associated with behavioural and psychological symptoms (BPSD) in a semi-residential setting. According to available evidence, DDCCs may decrease BPSD, depressive symptoms and caregiver burden. The present position paper reports a consensus of Italian experts of different disciplines regarding DDCCs and includes recommendations about architectural features, requirements of personnel, psychosocial interventions, management of psychoactive drug treatment, prevention and care of geriatric syndromes, and support to family caregivers. DDCCs architectural features should follow specific criteria and address specific needs of people with dementia, supporting independence, safety, and comfort. Staffing should be adequate in size and competence and should be able to implement psychosocial interventions, especially focused on BPSD. Individualized care plan should include prevention and treatment of geriatric syndromes, a targeted vaccination plan for infectious diseases including COVID-19, and adjustment of psychotropic drug treatment, all in cooperation with the general practitioner. Informal caregivers should be involved in the focus of intervention, with the aim of reducing assistance burden and promoting the adaptation to the ever-changing relationship with the patient.

Neuroprotective effects of resistance physical exercise on the APP/PS1 mouse model of Alzheimer's disease

Introduction

Physical exercise has beneficial effects by providing neuroprotective and anti-inflammatory responses to AD. Most studies, however, have been conducted with aerobic exercises, and few have investigated the effects of other modalities that also show positive effects on AD, such as resistance exercise (RE). In addition to its benefits in developing muscle strength, balance and muscular endurance favoring improvements in the quality of life of the elderly, RE reduces amyloid load and local inflammation, promotes memory and cognitive improvements, and protects the cortex and hippocampus from the degeneration that occurs in AD. Similar to AD patients, double-transgenic APPswe/PS1dE9 (APP/PS1) mice exhibit Αβ plaques in the cortex and hippocampus, hyperlocomotion, memory deficits, and exacerbated inflammatory response. Therefore, the aim of this study was to investigate the effects of 4 weeks of RE intermittent training on the prevention and recovery from these AD-related neuropathological conditions in APP/PS1 mice.

Methods

For this purpose, 6-7-month-old male APP/PS1 transgenic mice and their littermates, negative for the mutations (CTRL), were distributed into three groups: CTRL, APP/PS1, APP/PS1+RE. RE training lasted four weeks and, at the end of the program, the animals were tested in the open field test for locomotor activity and in the object recognition test for recognition memory evaluation. The brains were collected for immunohistochemical analysis of Aβ plaques and microglia, and blood was collected for plasma corticosterone by ELISA assay.

Results

APP/PS1 transgenic sedentary mice showed increased hippocampal Aβ plaques and higher plasma corticosterone levels, as well as hyperlocomotion and reduced central crossings in the open field test, compared to APP/PS1 exercised and control animals. The intermittent program of RE was able to recover the behavioral, corticosterone and Aβ alterations to the CTRL levels. In addition, the RE protocol increased the number of microglial cells in the hippocampus of APP/PS1 mice. Despite these alterations, no memory impairment was observed in APP/PS1 mice in the novel object recognition test.

Discussion

Altogether, the present results suggest that RE plays a role in alleviating AD symptoms, and highlight the beneficial effects of RE training as a complementary treatment for AD.

Comprehensive Geriatric Assessment: Application and correlations in a real-life cross-sectional study

Background

The assessment process of elderly people considers all aspects of an individual's life, including physical, mental, and social aspects. Frailty refers to a decline in physiological functions or strengths leading to increased vulnerability to stressors and decreased ability to cope with them. Comprehensive Geriatric Assessment (CGA) is a validated and useful tool in this context to holistically study elderly people. The primary aim of this study was to determine the prevalence of impaired health status in a large geriatric population turning to outpatient service, based on the components of the CGA, and thus to describe its usefulness in real-life clinical practice. The secondary aim of this study was the evaluation of the association between nutritional status, assessed with Mini Nutritional Assessment (MNA)-within the CGA-and cognitive-affective and functional capacities, and multimorbidity.

Materials and methods

This real-life, retrospective cross-sectional study included subjects consecutively evaluated from January 2009 to December 2020 at the Geriatric Outpatient Service, University Hospital of Monserrato, Cagliari, Italy. A sum of 3,260 patients were subjected to CGA.

Results

Only a small proportion of the sample (2.24%) showed an absence of impairment in cognitive-affective, functional, and nutritional domains. Moderate correlations were found between MNA and several other CGA variables, namely, Geriatric Depression Scale (GDS; ϱ = -0.41, p < 0.0001), Barthel Index of Independence in Activities of Daily Living (ADL) (ϱ = 0.51, p < 0.0001), Instrumental Activities of Daily Living (IADL) (ϱ = 0.43, p < 0.0001), and Performance-Oriented Mobility Assessment (ϱ = 0.44, p < 0.0001). A multiple regression also highlighted these variables as significant regressors of MNA. Finally, malnutrition showed a significant association with depression (odds ratio [OR]: 4.97), dependence on ADL (OR: 19.8) and IADL (OR: 7.04), and falling risk (OR: 5.16).

Conclusion

This study has figured out the complex situation in which geriatric care finds itself the complexity and severe impairment of elderly people. The possibilities of intervention are often limited, but the literature confirms the benefits of good nutritional status on the general health status. The data that emerged from our study fit into this assumption, highlighting the close association between the nutritional domain and the other CGA domains.