Effects of exercise therapy on global cognitive function and, depression in older adults with mild cognitive impairment: A systematic review and meta-analysis

Effects and neural mechanisms of different physical activity on major depressive disorder based on cerebral multimodality monitoring: a narrative review

Major depressive disorder (MDD) is currently the most common psychiatric disorder in the world. It characterized by a high incidence of disease with the symptoms like depressed mood, slowed thinking, and reduced cognitive function. Without timely intervention, there is a 20-30% risk of conversion to treatment-resistant depression (TRD) and a high burden for the patient, family and society. Numerous studies have shown that physical activity (PA) is a non-pharmacological treatment that can significantly improve the mental status of patients with MDD and has positive effects on cognitive function, sleep status, and brain plasticity. However, the physiological and psychological effects of different types of PA on individuals vary, and the dosage profile of PA in improving symptoms in patients with MDD has not been elucidated. In most current studies of MDD, PA can be categorized as continuous endurance training (ECT), explosive interval training (EIT), resistance strength training (RST), and mind-body training (MBT), and the effects on patients' depressive symptoms, cognitive function, and sleep varied. Therefore, the present study was based on a narrative review and included a large number of existing studies to investigate the characteristics and differences in the effects of different PA interventions on MDD. The study also investigated the characteristics and differences of different PA interventions in MDD, and explained the neural mechanisms through the results of multimodal brain function monitoring, including the intracranial environment and brain structure. It aims to provide exercise prescription and theoretical reference for future research in neuroscience and clinical intervention in MDD.

A methodological and reporting quality assessment of systematic reviews/meta-analyses on exercise interventions for cognitive function in older adults with mild cognitive impairment

Objective

To assess the methodological quality of meta-analytic literature on exercise interventions for cognitive function in patients with mild cognitive impairment (MCI) and the certainty of evidence for its outcome indicators, and to provide clinicians and researchers with more reliable data for making decisions.

Methods

Meta-analytic literature related to the effect of exercise intervention on cognitive function in patients with mild cognitive impairment was searched through PubMed, Cochrane Library, Embase, Scopus, Physiotherapy Evidence Database and Web of Science, all with a search period frame of each database until June 1, 2024. The AMSTAR2 scale was used to evaluate the methodological quality of the included studies.

Results

Seventeen meta-analyses were included. The AMSTAR2 scale evaluation results showed that there was one medium-quality studies (5.55%), seven low-quality studies (38.88%), and 10 very low-quality studies (55.55%). Methodological deficiencies included failure to prepare a plan and provide a registration number, literature screening, data extraction, reasons for exclusion not described in detail, poor implementation process for systematic evaluation, and failure to describe the source of funding for the included studies or relevant conflicts of interest.

Conclusion

The overall methodological quality of the meta-analytic literature is low, and the certainty of evidence is low. We encourage the conduction of high-quality randomized trials to generate stronger evidence. Subsequent systematic reviews can then synthesize this evidence to inform future research and clinical guidelines.

Comparative efficacy of seven nonpharmacological interventions on global cognition in older adults with and without mild cognitive impairment: a network meta-analysis of randomized controlled trials

To maintain current cognitive function and access greater cognitive reserves, nonpharmacological interventions may be a viable alternative for older adults with or without cognitive impairment. This study aimed to compare different nonpharmacological interventions for enhancing global cognition, including mind-body exercise, physical exercise, non-invasive brain stimulation, cognitive training intervention (CTI), acutherapy (ACU), meditation, and music therapy, by applying a network meta-analysis (NMA). Sixty-one randomized controlled trials evaluating the efficacy of interventions on global cognition in older adults with or without mild cognitive decline were selected. An NMA was conducted to compare the efficacy of different nonpharmacological interventions. The NMA revealed that mind-body exercise (standardized mean difference, 1.384; 95% confidence interval, 0.777-1.992); ACU (1.283; 0.478-2.088); meditation (0.910; 0.097-1.724); non-invasive brain stimulation (1.242; 0.254-2.230); CTI (1.269; 0.736-1.802); and physical exercise (0.977; 0.212-1.742), showed positive effects compared to passive controls. There were no significant differences between the efficacies of other interventions. Nonpharmacological interventions may potentially enhance and maintain global cognition through various pathways, such as memorizing movements and enhancing brain plasticity by reducing stress in the older adult population. Additional studies are needed to clarify the impact of other variables, including intervention methods or psychological variables.

Effects of Multicomponent Exercise on Community-Dwelling Older Adults With Mild Cognitive Impairment

PURPOSE

To explore the effects of a group-based multicomponent exercise program on general cognitive functioning, depression, and social functioning in community-dwelling older adults with mild cognitive impairment (MCI) and whether the effects can be maintained.

METHOD

Fifty older adults with MCI were conveniently recruited from two communities in the study area and randomly assigned to the intervention group or control group. The intervention group received three sessions of 60-minute, multicomponent exercise per week for 3 months, plus MCI-related health education. The control group only received MCI-related health education. Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment Beijing Version (MoCA-BJ) were used to assess general cognitive function. The Functional Activities Questionnaire (FAQ) and Geriatric Depression Scale (GDS-30) were used to evaluate participants' social function and depression, respectively. Participants' exercise intensity was assessed using the Category Ratio Scale.

RESULTS

After the 3-month intervention, there were significant improvements in general cognitive function (p = 0.046), attention (p = 0.009), delayed recall (p = 0.015), and social function (p = 0.011) in the intervention group compared with the control group. However, after 3-month postintervention follow up, no significant differences in MMSE, MoCA-BJ, GDS-30, and FAQ scores were noted between groups.

CONCLUSION

The 3-month multicomponent exercise program improved general cognitive function and social functioning in community-dwelling older adults with MCI. However, there was no evidence that these benefits lasted for another 3 months after stopping the exercise program. [Research in Gerontological Nursing, 17(2), 65-79.].

Major Depressive Disorder and Gut Microbiota: Role of Physical Exercise

Major depressive disorder (MDD) has a high prevalence and is a major contributor to the global burden of disease. This psychiatric disorder results from a complex interaction between environmental and genetic factors. In recent years, the role of the gut microbiota in brain health has received particular attention, and compelling evidence has shown that patients suffering from depression have gut dysbiosis. Several studies have reported that gut dysbiosis-induced inflammation may cause and/or contribute to the development of depression through dysregulation of the gut-brain axis. Indeed, as a consequence of gut dysbiosis, neuroinflammatory alterations caused by microglial activation together with impairments in neuroplasticity may contribute to the development of depressive symptoms. The modulation of the gut microbiota has been recognized as a potential therapeutic strategy for the management of MMD. In this regard, physical exercise has been shown to positively change microbiota composition and diversity, and this can underlie, at least in part, its antidepressant effects. Given this, the present review will explore the relationship between physical exercise, gut microbiota and depression, with an emphasis on the potential of physical exercise as a non-invasive strategy for modulating the gut microbiota and, through this, regulating the gut-brain axis and alleviating MDD-related symptoms.

Comparative efficacy of various exercise interventions on depression in older adults with mild cognitive impairment: A systematic review and network meta-analysis

BACKGROUND

Exercise is a promising nonpharmacological treatment for improving depression in older adults with MCI, but it is unclear which exercises are most effective. The objectives of this study were to compare and rank the effectiveness of various exercise interventions for depression in mild cognitive impairment (MCI) and to investigate the effects of exercise on depression.

METHODS

The PRISMA-NMA guidelines were applied to the development and reporting of review criteria. The Cochrane Library, Web of Science, PsycINFO, PubMed, EMBASE, CINAHL, and Scopus databases were systematically searched by combining search terms for randomized controlled trial studies (RCTs) published in English from individual databases with the earliest available date set to March 10, 2023. Two evaluators independently selected and evaluated eligible studies of changes in depression in older adults with MCI after an exercise intervention. A protocol for this systematic review was registered in PROSPERO (Registration number: CRD42022377052).

RESULTS

A network meta-analysis was conducted on 15 eligible RCTs consisting of 4271 subjects, including aerobic (n = 6), mind-body (n = 6) and multicomponent (n = 3) exercise trials. Compared to controls, mind-body exercise showed the strongest improvement in depressive symptoms (SMD = -0.63, 95% CI: -1.13, -0.14), followed by aerobic (SMD = -0.57, 95% CI: -0.88, -0.26) and multicomponent exercise (SMD = -0.53, 95% CI: -1.02, -0.03). Notably, there were no statistically significant differences between exercise types: aerobic vs. mind-body (SMD = 0.06, 95% PrI: -0.71, 0.84), multicomponent vs. mind-body (SMD = 0.11, 95% PrI: -0.75, 0.97), or multicomponent vs. aerobic (SMD = 0.04, 95% PrI: -0.771, 0.86).

CONCLUSIONS

In this review, we found that mind-body exercise was most effective when compared to conventional controls and that multiple exercise modalities (aerobic, mind-body, and multicomponent exercise) had beneficial and comparable effects in reducing depressive states in older adults with MCI. These findings may guide clinical geriatric stakeholders and allied health professionals in providing more scientifically optimal exercise prescriptions for older adults with MCI. In the future, more high-quality, long-term clinical trials are needed to support the exploration of longer-term dynamic effects.

Effects of multimodal cognitive exercise program on cognitive function, bone density, blood lipid, fitness, and depression in old women with mild cognitive impairment

The purpose of this study is to verify the effects of participation in 12-week multimodal cognitive exercise program on cognitive function, bone mineral density, blood lipids, senior functional fitness, and depression of the old women with mild cognitive impairment and osteopenia. As a result, the exercise group showed significant effects in cognitive function, depression, bone mineral density, blood lipid, lower extremity flexibility, upper extremity flexibility, dynamic balance, and body endurance. Such results prove that multimodal cognitive exercise program is an effective interventional exercise program for improving cognitive function in the old women with mild cognitive impairment.