Physical activity is associated with better global cognition and frontal function in overweight/obese older adults with metabolic syndrome

Effects of exercise interventions on brain-derived neurotrophic factor levels in overweight and obesity: A systematic review and meta-analysis

Background

/Objective. An explosion in global obesity epidemic poses threats to the healthcare system by provoking risks of many debilitating diseases, including cognitive dysfunction. Physical activity has been shown to alleviate the deleterious effects of obesity-associated cognitive deficits across the lifespan. Given the strong neuroprotective role of brain-derived neurotrophic factor (BDNF) and exercise training as a known modulator for its elevation, this systematic review sought to examine the strength of the association between exercise and BDNF levels in healthy people with overweight and obesity.

Methods

Six electronic databases (PubMed, MEDLINE, EMBASE, Web of Science, Ovid Nursing Database, and SPORTDiscus) were searched from their inceptions through December 2022. The primary outcome of interest was BDNF levels. Interventional studies (randomized and quasi-experimental) with English full text available were included. Risk of bias of the included studies was assessed using the Physiotherapy Evidence Database Scale. Data were extracted for meta-analyses by random-effects models.

Results

Thirteen studies (n = 750), of which 69.2% (9/13) had low risk of bias, were included. In the meta-analysis, exercise interventions had no significant effect on resting BDNF levels (standardized mean difference: -0.30, 95% CI -0.80 to 0.21, P = 0.25). Subgroup analyses also indicated no effects of age and types of control groups being compared on moderating the association.

Conclusion

To further inform the role of BDNF in obesity-related cognitive functioning, rigorous studies with larger samples of participants and raw data available were imperatively deserved.

Enhancing physical function and activity level in malnourished older adults through oral nutrition supplements: a randomized controlled trial

BACKGROUND

Malnutrition of older individuals, leads to significant functional decline, reducing their quality of life. Lifestyle interventions; dietary improvements and supplementation are explored to enhance the physical function of older adults. The current study aimed to assess the impact of oral nutritional supplements (ONS) on the functional and activity levels of Sri Lankan older adults.

METHODS

This randomized controlled trial included; an intervention group (IG) receiving 200 mL of ONS providing 247 kcal per serving, for 12 weeks and a control group (CG) receiving an equivalent volume of water. Changes in handgrip strength, knee extension strength, gait speed, functional and activity levels were assessed.

RESULTS

The IG showed significant improvements in handgrip strength (43.96 ± 18.61 kg vs. 32.81 ± 17.92 kg; p < 0.001) and knee extension strength (23.45 ± 2.29 kg vs. 16.41 ± 2.09 kg; p < 0.001) following 12 weeks compared to the CG. The IG also exhibited significant improvements in gait speed (1.31 ± 0.52 m/s vs. 0.87 ± 0.26 m/s), Barthel index score, (0.30 ± 0.47 vs. -0.18 ± 0.66), PASE score (0.52 ± 17.79 vs. -1.60 ± 21.77) and IPAQ categories.

CONCLUSIONS

ONS was found to be effective in improving the functional and physical activity levels of malnourished older adults.

TRIAL REGISTRATION

Sri Lanka Clinical Trial Registry SLCTR/2022/021. Registered on 06/10/2022.

Exercise Reshapes the Brain: Molecular, Cellular, and Structural Changes Associated with Cognitive Improvements

Physical exercise is well known as a non-pharmacological and holistic therapy believed to prevent and mitigate numerous neurological conditions and alleviate ageing-related cognitive decline. To do so, exercise affects the central nervous system (CNS) at different levels. It changes brain physiology and structure, promoting cognitive improvements, which ultimately improves quality of life. Most of these effects are mediated by neurotrophins release, enhanced adult hippocampal neurogenesis, attenuation of neuroinflammation, modulation of cerebral blood flow, and structural reorganisation, besides to promote social interaction with beneficial cognitive outcomes. In this review, we discuss, based on experimental and human research, how exercise impacts the brain structure and function and how these changes contribute to cognitive improvements. Understanding the mechanisms by which exercise affects the brain is essential to understand the brain plasticity following exercise, guiding therapeutic approaches to improve the quality of life, especially in obesity, ageing, neurodegenerative disorders, and following traumatic brain injury.

Effect of exercise interventions on brain-derived neurotrophic factor expression in people with overweight and obesity: protocol for a systematic review and meta-analysis

INTRODUCTION

Epidemic obesity ('globobesity') has led to a considerable rise in the prevalence and incidence of many disabling conditions, including cognitive dysfunction. Recent evidence has suggested that habitual exercise can alleviate the deleterious effects of obesity on cognitive functioning across the lifespan. Given that there is a potential link among obesity, exercise, cognitive health and brain-derived neurotrophic factor (BDNF), this systematic review aims to critically appraise interventional trials on exercise and BDNF and to estimate the pooled effect of exercise training on BDNF levels among healthy individuals with overweight and obesity.

METHODS AND ANALYSIS

Six electronic databases-PubMed, MEDLINE, EMBASE, Web of Science, Ovid Nursing Database and SPORTDiscus-will be searched from their inception through December 2022. Only interventional studies, including randomised controlled trials and quasi-experimental studies, with full text available and reported in English will be included. The primary outcomes will be changes in BDNF levels among healthy subjects with overweight and obesity following either acute or chronic bouts of exercise interventions. Two reviewers will independently conduct data extraction and risk of bias assessment for included trials using the Physiotherapy Evidence Database Scale. We will produce a narrative synthesis, with findings categorised by sex, age groups and types of exercise training. Data will be extracted and pooled for meta-analyses using random-effects models.

ETHICS AND DISSEMINATION

No formal ethical approval is required for this systematic review. The findings of this review will be disseminated through peer-reviewed publications.

PROSPERO REGISTRATION NUMBER

CRD42023414868.

Two-Year Changes in Physical Activity and Concurrent Changes in Cognitive Function in a Cohort of Adults with Metabolic Syndrome

BACKGROUND

It has been proposed that physical activity (PA) could prevent cognitive decline.

OBJECTIVE

To evaluate the association between changes in PA and changes in cognitive function in a cohort of adults with metabolic syndrome.

METHODS

Longitudinal observational study including 5,500 adults (mean age 65 years, SD = 5; women = 49.3% ) with metabolic syndrome. Participants underwent physical activity measurements and cognitive evaluation at baseline and at two-years of follow-up. PA was quantified using the Minnesota questionnaire-shortened version. Cognitive function was evaluated using a battery of tests: Mini-Mental Test Examination, Clock Drawing Test, Trail Making Test A and B, Verbal Fluency Test, and Digit Span. The primary outcome was two-year change in cognition, measured through the Global Composite Score (GCS) of all neuropsychological tests. Multivariable-adjusted linear regression models were fitted with baseline PA and their changes as the main exposures and changes in cognitive function as the outcome.

RESULTS

No significant association was found between PA levels (or their changes) in the GCS of cognitive function. A greater increase in PA levels was associated with a more favorable two-year change in the Trail Making Test A (Q4 versus Q1: b = - 2.24s, 95% CI -4.36 to -0.12s; p-trend = 0.020). No significant association was found for other neuropsychological test.

CONCLUSION

Our results do not support an association between increases in PA and the evolution of the global cognitive function at two-year in an intervention trial which included PA promotion in one of its two randomized arms, but they suggested a possible beneficial effect of PA on attentional function in older adults.

Cognitive Benefits of Physical Exercise, Physical-Cognitive Training, and Technology-Based Intervention in Obese Individuals with and without Postmenopausal Condition: A Narrative Review

Obesity and estrogen deprivation have been identified as significant risk factors for cognitive impairment. Thus, postmenopausal conditions when paired with obesity may amplify the risks of developing dementia. Physical exercise has been recommended as a primary treatment for preventing obesity-related comorbidities and alleviating menopausal symptoms. This narrative review aimed to summarize the effects of exercise on cognition in obese individuals with and without menopausal condition, along with potential physiological mechanisms linking these interventions to cognitive improvement. Research evidence has demonstrated that exercise benefits not only physical but also cognitive and brain health. Among various types of exercise, recent studies have suggested that combined physical-cognitive exercise may exert larger gains in cognitive benefits than physical or cognitive exercise alone. Despite the scarcity of studies investigating the effects of physical and combined physical-cognitive exercise in obese individuals, especially those with menopausal condition, existing evidence has shown promising findings. Applying these exercises through technology-based interventions may be a viable approach to increase accessibility and adherence to the intervention. More evidence from randomized clinical trials with large samples and rigorous methodology is required. Further, investigations of biochemical and physiological outcomes along with behavioral changes will provide insight into underlying mechanisms linking these interventions to cognitive improvement.

Benefits of and barriers to telehealth for the informal caregivers of elderly individuals in rural areas: A scoping review

INTRODUCTION

Maintaining care for elderly individuals in rural areas is heavily dependent on support from informal caregivers. Many informal caregivers of the elderly in rural areas feel burdened and urgently require professional support. Interests in telehealth that can provide support irrespective of geographical location have been increasing.

OBJECTIVE

To identify the benefits of and barriers in telehealth engagement for rural caregivers to provide evidence for service improvement.

DESIGN

A scoping review method was used following PRISMA-ScR guidelines and Arksey and O'Malley's five-stage framework. Five databases were searched. The search terms were chosen based on the target intervention (i.e. telehealth), target population (caregivers of elderly individuals) and target context (rural areas). Two authors independently assessed the eligibility of studies and extracted data from eligible studies.

FINDINGS

Of 4220 retrieved studies, 19 articles met the inclusion criteria. This study identified four benefits of and two barriers to telehealth for rural caregivers. Four subthemes were identified as the key benefits in using telehealth for caregivers: decrease in psychological distress, increase in care efficiency, increase in social support and increase in access to resources, while inadequate telehealth infrastructures and caregivers' own reasons were the primary barriers in using telehealth for those populations.

CONCLUSIONS

Telehealth was shown to significantly benefit rural caregivers. Future research can be designed and conducted for overcoming the barriers to telehealth. Additionally, the benefits identified by this review need to be translated from research into practice for rural caregivers' care.

Physical Activity Is Associated with Improved Visuomotor Processing in Older Adults with Moderate and Advanced Glaucomatous Visual Field Defect: A Cross-Sectional Study

Glaucoma affects a wide spectrum of daily essential activities in older adults. This study examined whether older adults with moderate and advanced stages of glaucoma exhibit differences in visuomotor task performance compared with age- and gender-matched ophthalmologically healthy control subjects and estimated the effects of physical activity (PA) levels, age, and severity of visual impairment on patients' visuomotor task performance. Sixty older adults with moderate glaucoma, advanced glaucoma, and normal sight participated in the study. Visuomotor processing was assessed using laboratory-based simple and complex visuomotor reaction tasks. Monocular Humphrey Visual Field and binocular Humphrey Esterman Visual Field tests were used to estimate visual field defect severity. The International Physical Activity Questionnaire was used to assess PA levels. Participants with glaucoma had poorer scores in visuomotor tasks compared to participants with normal sight. Glaucoma patients' PA levels, age, and binocular visual field defect explained 54% of the variation in complex reaction time. Low PA levels were identified as a risk factor for visuomotor processing decline. Compensatory mechanisms to improve the efficiency of visual field scanning in patients with more severe visual field defects may exist.

Arterial stiffness and age moderate the association between physical activity and global cognition in older adults

BACKGROUND

Evidence supports that time spent on physical activity has beneficial effects on cognition in older adults. Nevertheless, whether these beneficial effects are still present at the intersection of different levels of arterial stiffness and age is uncertain.

METHODS

One hundred and ten healthy older adults aged 60-75 years were examined for arterial stiffness [carotid-femoral pulse wave velocity (cf-PWV)], global cognition (composite score of Montreal Cognitive Assessment, and Mini-Mental State Examination), and self-reported physical activity (PACED diary). Using PROCESS macro for SPSS, we evaluated if cf-PWV (moderator 1), and age (moderator 2) moderate the relationship between physical activity (X) and global cognition (Y). The threshold for high stiffness was set at 8.5 m/s based on previous studies that reported this cut-off as more appropriate for classifying cerebrovascular risk groups.

RESULTS

Physical activity had a positive effect on cognition in young-elderly adults (<68.5 years) with a cf-PWV of at least 8.5 m/s (β = 0.48, SE = 0.193, P = 0.014, 95% CI = 0.100--0.868) and in elderly adults (≥68.5 years) with a cf-PWV of less than 8.5 m/s (β = 0.56, SE = 0.230, P = 0.017, 95% CI = 0.104-1.018). This was not the case in elderly adults with a cf-PWV of at least 8.5 m/s (β = 0.00, SE = 0.193, P = 0.998, 95% CI = -0.362 to 361), or in young-elderly adults with a cf-PWV of less than 8.5 m/s (β = 0.16, SE = 0.247, P = 0.501, 95% CI = -0.326 to 656).

CONCLUSION

The interaction between arterial stiffness and age moderated the effect of physical activity on global cognition. Time spent on physical activity alone might not be sufficient to achieve cognitive benefit over a specific threshold of arterial stiffness and age.

Body mass index and cognitive decline among community-living older adults: the modifying effect of physical activity

Objective

To examine the associations between BMI categories and subsequent 3-year cognitive decline among older adults, and to test whether physical activity modifies the associations.

Methods

Study sample included n = 1028 cognitively unimpaired older adults participating in the Étude sur la Santé des Aînés (ESA)-Services longitudinal study and followed 3 years later. Cognitive decline was defined as a decrease of > 3 points in MMSE scores between baseline and follow-up. BMI categories (normal weight (reference), underweight, overweight, obese) were derived from self-reported weight and height. Moderate to vigorous physical activity of ≥20 min (# of times per week) was self-reported. The presence of chronic disorders was ascertained from administrative and self-reported data. Logistic regression analyses were used to study the risk of cognitive decline associated with BMI categories stratified by weekly physical activity (≥140 min), the presence of metabolic, cardiovascular and anxio-depressive disorders.

Results

In the overall sample, there was no evidence that underweight, overweight, or obesity, as compared to normal weight, was associated with cognitive decline, after adjusting for sociodemographic, lifestyle factors, and comorbidities. Individuals with overweight reporting high physical activity had lower odds of cognitive decline (OR = 0.25, 95% CI = 0.07–0.89), whereas no association was observed in individuals with overweight reporting low physical activity (OR = 0.85, 95% CI = 0.41–1.75). Among participants with metabolic and cardiovascular disorders, individuals with overweight reporting high physical activity had lower odds of cognitive decline (OR = 0.09, 95% CI = 0.01–0.59 and OR = 0.03, 95% CI = 0.01–0.92 respectively), whereas no association was observed in those with low physical activity.

Conclusion

Physical activity modifies the association between overweight and cognitive decline in older adults overall, as in those with metabolic and cardiovascular disorders. Results highlight the importance of promoting and encouraging regular physical activity in older adults with overweight as prevention against cognitive decline.

Supplementary Information

The online version contains supplementary material available at 10.1186/s11556-022-00284-2.

The association between meal specific low carbohydrate diet score and cardiometabolic risk factors: A cross-sectional study of Iranian adults

BACKGROUND AND AIM

Since evidence regarding low-CHO diet and cardiometabolic risk factors is controversial, this study aimed to assess the relation between low-CHO diet score and metabolic syndrome (MetS) and cardiometabolic risk factors among a group of Iranian adults.

METHODS

This cross-sectional study was conducted with 840 subjects with the age range of 20-65 years. Dietary intakes were assessed by completing three 24-hour recalls. Total, animal- and vegetable-based low-CHO diet score were calculated. We used logistic regression with different models to determine whether there were relationships between low-CHO diet score and MetS and MetS components.

RESULTS

We found that there was no significant association between low-CHO diet, animal-based and vegetable-based low-CHO diet scores and risk of MetS in three meals. Except for the animal-based low-CHO diet score, which was significantly associated with general obesity at lunch meal (OR: 1.17, 95% CI: 0.76-1.82, P = .03). There were a significant association between low-CHO diet and high-density lipoprotein cholesterol (HDL-C) levels in lunch meal (OR: 1.50, 95% CI: 1.06-2.14, P = .03). Vegetable-based low-CHO diet score was associated with a lower risk of elevated TG in lunch meal in the fully adjusted model (OR: 0.59, 95% CI: 0.39-0.90, P = .04).

CONCLUSION

Diets with lower amounts of carbohydrate and higher contents of fat and protein were not significantly associated with the risk for MetS in Iranian adults. Only animal-based low-CHO diet score was significantly associated with general obesity at lunch meal.

The relationship between diabetes-related cognitive dysfunction and leukoaraiosis

Cognitive dysfunction is a degenerative disease of the central nervous system, which often associates with ageing brain as well as neurodegenerative diseases. A growing body of evidence suggests that patients with diabetes mellitus (DM) have a significantly higher risk of cognitive impairment. In recent years, studies have found that patients with diabetes-related cognitive dysfunction have an increased burden of leukoaraiosis (LA), and larger white matter hyperintensity (WMH) volume. With the recent advancement of technologies, multimodal imaging is widely exploited for the precise evaluation of central nervous system diseases. Emerging studies suggest that LA pathology can be used as a predictive signal of white matter lesions in patients with diabetes-related cognitive dysfunction, providing support for early identification and diagnosis of disease. This article reviews the findings, epidemiological characteristics, pathogenesis, imaging features, prevention and treatment of LA pathophysiology in patients with diabetes-related cognitive dysfunction.

Interaction of physical activity on the association of obesity-related measures with multimorbidity among older adults: a population-based cross-sectional study in India

OBJECTIVE

To explore the associations between obesity-related measures and multimorbidity among older Indian adults and the interactive effects of physical activity in those associations.

DESIGN

A cross-sectional study was conducted using large representative survey data.

SETTING AND PARTICIPANTS

The present study used data from the Longitudinal Aging Study in India (LASI) conducted during 2017-2018. Participants included 15 098 male and 16 366 female older adults aged 60 years and above in India.

PRIMARY AND SECONDARY OUTCOME MEASURES

The outcome variable was multimorbidity among older adults coded as no and yes. Descriptive statistics along with bivariate analysis are presented in the paper. Additionally, binary logistic regression analysis was used to fulfil the study objectives.

RESULTS

About 24% of older adults in the LASI cohort suffered from multimorbidity. Older adults who were overweight/obese (adjusted OR (AOR): 1.61, CI 1.48 to 1.74), had high-risk waist circumference (AOR: 1.66, CI 1.52 to 1.80) and had high-risk waist to hip ratio (AOR: 1.45, CI 1.33 to 1.59) were significantly more likely to suffer from multimorbidity compared with their counterparts. Older adults who were obese and physically inactive had significantly increased odds of suffering from multimorbidity compared with older adults who were obese and physically active. Similarly, older adults with high-risk waist circumference (AOR: 1.30, CI 1.11 to 1.53) and high-risk waist to hip ratio (AOR: 1.32, CI 1.20 to 1.46) along with being physically inactive had significantly higher odds of suffering from multimorbidity in comparison with older adults with high-risk waist circumference and waist to hip ratio along with being physically active.

CONCLUSION

While developing health strategies for older adults, physical activity needs to be recognised as a way of minimising comorbidities. Further, the study highlights the importance of using multiple obesity-related measures to predict chronic conditions in the older population.