Effects of Physical Activity Intervention on Physical and Cognitive Function in Sedentary Adults With and Without Diabetes

Changes in physical activity during the year after the Great East Japan Earthquake and future frailty in older survivors

AIM

This study examines whether changes in physical activity (PA) during the first year after the Great East Japan Earthquake and Tsunami (2011-2012) contributed to preventing the onset of future frailty among older survivors of the disaster.

METHODS

This study tracked 2561 physically active Japanese survivors aged ≥ 65 years (43.6% men; mean age 72.9 years) who had completed self-administered questionnaires in 2011 and 2012. PA levels for participants were classified into four categories based on ≥23 and <23 metabolic equivalent hours/week in 2011 and 2012: "consistently low," "decreasing," "increasing," and "consistently high." Frailty was defined as a Kihon Checklist score ≥ 5, which is used in the long-term care insurance system in Japan. Hazard ratios were calculated for the onset of frailty using a Cox proportional hazards model that fitted the proportional sub-distribution hazards regression model with weights for competing risks of death.

RESULTS

From 2012 to 2018, 283 men and 490 women developed frailty. Men with consistently high or increasing PA during the first year after the disaster had a lower risk of frailty. Furthermore, even increasing PA by walking for just 30 min/day prevented future frailty in men; however, this association between a change in PA and the decreased risk of frailty was not observed in women.

CONCLUSIONS

Older men who remained physically active or resumed PA at an early stage and at a low intensity, even after being physically inactive owing to the disaster, were able to prevent future frailty. Geriatr Gerontol Int 2024; 24: 563-570.

Association Between Physical Activity and Physical Function in a Marshallese Population with Type 2 Diabetes

Physical activity can delay functional decline in people with type 2 diabetes (T2D), but these associations have not been studied within a sample of Native Hawaiian or Pacific Islander adults with T2D. Using data from a randomized control trial in which 218 Marshallese adults with T2D participated in a 10-week diabetes self-management education intervention, this study tested our hypothesis that physical activity would predict physical function when controlling for time and other variables. Levels of physical activity were positively associated with levels of physical function, even after controlling for time and other covariates. These findings provide a more robust understanding of the relationship between physical activity and physical function in a sample of minority adults with T2D. Future studies should further explore levels of physical activity needed to maintain and improve physical function so that culturally appropriate physical activity interventions can be developed.

Physical Activity Moderates the Relationship between Cardiovascular Disease Risk Burden and Cognition in Older Adults

INTRODUCTION

Older individuals with a higher cardiovascular disease (CVD) burden have a higher risk for accelerated cognitive decline and dementia. Physical activity (PA) is an inexpensive and accessible preventive measure to CVD, cognitive impairment, and dementia. The current study examined (1) whether PA moderates the relationship between CVD burden and cognition and (2) whether the moderating effect of PA differs by race/ethnicity groups and by APOE-ɛ4 status.

METHODS

Our cross-sectional study included participants from the Washington Heights-Inwood Columbia Aging Project (WHICAP), a multiethnic, community-based, longitudinal study on aging and dementia among individuals aged 65 years and older who reside in northern Manhattan. All participants underwent an interview and a neuropsychological assessment for global cognition, memory, language, visuospatial, and speed functioning.

RESULTS

In 2,122 older individuals without dementia, having a higher CVD burden was associated with worse cognitive scores for global, language, speed, and visuospatial cognitive functions. PA mitigated the relationship between CVD burden and visuospatial function. Furthermore, PA mitigated the association of CVD burden with global cognition, language, and visuospatial functions in APOE-ɛ4 carriers but not in non-carriers.

DISCUSSION/CONCLUSION

Our study suggests that PA may mitigate the negative association between CVD and cognition, especially in APOE-ɛ4 carriers. The moderating effect of PA did not differ by race/ethnicity.

Feasibility and preliminary efficacy of different intensities of functional training in elderly type 2 diabetes patients with cognitive impairment: a pilot randomised controlled trial

BACKGROUND

Aging and type-2 diabetes (T2D) are the most important risk factors for cognitive impairment and Alzheimer's disease. Exercise training is an effective, safe, and practical intervention in improving glucose metabolism, physical function, and cognitive disorders. This pilot study investigated the feasibility and preliminary efficacy of high-intensity low-volume (HIFT) vs. low-intensity high-volume (LIFT) functional training in elderly T2D patients with cognitive impairment.

METHODS

Forty-eight elderly T2D patients (31 female, 17 male, age 67.5 ± 5.8 years, MMSE score 18.8 ± 2.6, FBG 209.5 ± 37.9) were randomly assigned to HIFT, LIFT and control groups. Cognitive impairment was diagnosed with MMSE ≤ 23 based Iranian society. The SDMT, CVLT-II, BVMT-R, and Stroop tests were used to evaluated processing speed, learning, memory and attention respectively. Physical fitness tests include: tandem stance and walk test; TUG; 6MWT, 10MWT; SSST; 5TSTS; and hand grip was used to evaluated static and dynamic balance, agility, walking endurance, gait speed, lower limb function and lower and upper body strength respectively. As well as, Biochemical (FBG, insulin, HOMA-IR, HbA1c) and physiological outcomes (SBP, and DBP) were assessed. The HIFT group performed six weeks of functional training (three sessions per week) with 120-125% of the lactate threshold. The LIFT group performed six weeks of functional training (five sessions per week) with a 70-75% lactate threshold. Feasibility, safety, and acceptability of exercise programs were assessed at the end of the study.

RESULT

HIFT showed a higher adherence rate (91% vs. 87.5%), safety, and acceptability compared to LIFT. MMSE and Stroop scores, 6MWT, FBG, insulin, HOMA-IR, HbA1c, SBP, and DBP significantly improved in HIFT (all, P ≤ 0.004) and LIFT (all, P ≤ 0.023). Changes in 6MWT, FBG, insulin, HOMA-IR, and HbA1c in HIFT (all, P ≤ 0.001) and LIFT (all, P ≤ 0.008) were significant compared to the control group. Changes in Stroop scores were significant only in the HIFT group compared to the control group (P = 0.013). SDMT, CVLT-II, BVMT-R, balance test, 10MWT, SSST, TUG and hang grip significantly improved only in HIFT (all, P ≤ 0.038).

CONCLUSION

HIFT vs. LIFT is a safe, feasible, and effective approach for improving some aspects of physical, biochemical, and cognitive function in elderly T2D patients with cognitive impairment. This pilot study provides initial proof-of-concept data for the design and implementation of an appropriately powered randomised controlled trial (RCT) of HIFT vs. LIFT in a larger sample of elderly T2D patients with cognitive impairment.

TRIAL REGISTRATION

Randomized controlled trial (RCT) (Iranian Registry of Clinical Trials, trial registration number: IRCT20230502058055N1. Date of registration: 11/06/2023.

Review articles (Meta-Analyses) effects of walking on cognitive function in individuals with mild cognitive impairment: a systematic review and meta-analysis

BACKGROUND

Mild cognitive impairment (MCI) is the stage between the expected cognitive decline of normal aging and the more serious decline of dementia. Previous studies have shown that regular exercise can improve cognition and physical performance in older adults. Walking is a low-technology and low-cost exercise that has been proven to improve cognition and mobility in healthy elderly individuals. However, no systematic review or meta-analysis has explored whether walking can improve cognitive function in older adults with MCI. This study aimed to explore the effects of walking interventions on cognitive functions in individuals with MCI.

METHODS

In accordance with the PRISMA guidelines, MEDLINE, PubMed, SPORTDiscus, Cochrane Central Register of Controlled Trials, CINAHL, Web of Science, Airiti Library, and the National Digital Library of Theses and Dissertations in Taiwan were searched from inception to July 2023. Independent reviewers selected randomized clinical trials (RCT) that compared the effects of walking with no intervention or other exercises in individuals with MCI. The primary outcomes were cognitive functions, and the secondary outcome was walking endurance. Three reviewers independently conducted data extraction. The risk of bias was assessed using the Revised Cochrane Risk of Bias assessment tool.

RESULTS

Fourteen RCTs were included in this review. The quality of evidence in these studies was rated as good to excellent. The results of the meta-analysis showed that the individuals with MCI had no significant improvement in cognitive function but had significant improvement in the 6-min walk test (Mean Difference=23.70, p=0.008) after walking interventions compared to no intervention or other exercises.

CONCLUSION

Walking intervention has no significant improvement on cognitive functions in older adults with MCI. However, walking induces beneficial effects on aerobic capacity.

TRIAL REGISTRATION

This systematic review has the registration number CRD42021283753 on PROSPERO.

Threshold effects of the relationship between physical exercise and cognitive function in the short-sleep elder population

Background

It has been demonstrated that elderly people's cognitive capacities can be improved with exercise, and short sleep is linked to cognitive decline. However, the impact of physical exercise on cognitive performance in seniors who do not get enough sleep is largely unknown. This makes it an intriguing subject to explore further.

Methods

This study consisted of elders (over 60 years old) who participated throughout the National Health and Nutrition Examination Survey's 2011-2014 cycle (NHANES). Weighted linear regression model and restricted cubic splines analysis were performed to evaluate the association between physical exercise and cognitive function. In the end, 1,615 samples were scrutinized and the total number of weighted respondents was 28,607,569.

Results

Results showed that in the Animal Fluency test and the Digit Symbol Substitution test, a positive association was found between physical exercise volume and scores in the fully adjusted model. A two-piecewise linear regression model was then applied to explore the threshold effect of exercise on cognitive performance. Before 960 and 800 MET-minutes/week, there were consistent positive relationship between exercise and scores of the Animal Fluency test [ß (95% CI): 0.233 (0.154, 0.312), p < 0.001] and Digit Symbol Substitution test [β (95% CI): 0.555 (0.332, 0.778), p < 0.001], respectively. However, there was a saturation effect where physical exercise volume reached the two inflection points.

Conclusion

According to our research, the benefit of exercise did not always expand with the exercise volume increment under the short-sleep condition, which challenged existing knowledge. The short-sleep elder group could maintain cognitive performance with no more than 800 MET-minutes/week of physical exercise. Verification of these findings requires further biological investigations.

Association of leisure activity changes and reversion from mild cognitive impairment to normal cognitive function among older adults: A prospective cohort study

Background

Older adults with mild cognitive impairment (MCI) have the possibility of reverting to normal cognitive function. Leisure activity engagement (LAE) plays a critical role in the progress of the cognitive function. A better understanding of the dynamic relationship between LAE and MCI reversion would inform the implementation of preclinical dementia interventions. This study aimed to investigate the association between change patterns of LAE and MCI reversion among older adults using the Chinese Longitudinal Healthy Longevity Survey (CLHLS) database.

Study design

Longitudinal population-based study.

Methods

Older adults with MCI at the baseline were enrolled in this study. Information about cognitive function, overall, cognitively stimulating, physically active/demanding, and socially engaged LAE was collected at baseline and follow-up. Adjusted hazard ratios (HRs) for reversion and 95% confidence intervals (CIs) were calculated by Cox hazard models with time as the underlying time metric. We also assessed potential effect modifications by creating a cross-product of the stratifying variable with LAE change patterns in the fully adjusted model.

Results

The restricted cubic spline showed that the association between LAE change scores and MCI reversion rate was statistically significant and nonlinear (p<0.01). Taking participants in the low-low group as a reference, participants in the low-medium, low-high, medium-medium, medium-high, high-medium, and high-high groups had increased possibilities of MCI reversion with HRs (95% CI) of 2.19 (1.57-3.06), 2.97 (2.13-4.13), 0.87 (0.64-1.19), 2.28 (1.71-3.03), 2.78 (2.10-3.69), 1.93 (1.43-2.59), and 2.74 (2.09-3.60), respectively. Further stratified models showed that the impact of LAE change patterns on MCI reversion varied in different ages (nonagenarian, octogenarian, and younger elderly) and gender.

Conclusions

Participants who maintained the highest LAE had the greatest possibility of MCI reversion. Meanwhile, a higher level of LAE maintenance was associated with the increased possibility of MCI reversion. These results provide a practical message to older adults about how dynamic changes in LAE are associated with improved cognitive function.

Distal radius fractures and risk of incident neurocognitive disorders in older adults: a retrospective cohort study

INTRODUCTION

Distal radius fractures (DRF) are associated with increased risk of subsequent fractures and physical decline in older adults. This study aims to evaluate the risk cognitive decline following DRF and potential for timely screening and intervention.

METHODS

A cohort of 1046 individuals 50-75 years of age with DRF were identified between 1995 and 2015 (81.5% female; mean age 62.5 [± 7.1] years). A control group (N = 1044) without history of DRF was matched by age, sex, and fracture date (i.e., index). The incidence of neurocognitive disorders (NCD) in relation to DRF/index was determined. Group comparisons were adjusted by age and comorbidity measured by the Elixhauser index.

RESULTS

The DRF group had a greater incidence of NCD compared to the control group (11.3% vs. 8.2%) with a 56% greater relative risk (HR = 1.56, 95% Cl: 1.18, 2.07; p = 0.002) after adjusting for age and comorbidity. For every 10-year age increase, the DRF group was over three times more likely to develop a NCD (HR = 3.23, 95% Cl: 2.57, 4.04; p < 0.001).

CONCLUSION

DRF in adults ages 50 to 75 are associated with increased risk of developing neurocognitive disorders. DRF may represent a sentinel opportunity for cognitive screening and early intervention. Distal radius fractures (DRF) have been associated with greater risk of future fractures and physical decline. This study reports that DRF are also associated with greater risk of developing neurocognitive disorders in older adults. Timely intervention may improve early recognition and long-term outcomes for older adults at risk of cognitive decline.

Effect of Exercise on the Cognitive Function of Older Patients With Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

Background

Aging and type 2 diabetes mellitus (T2DM) are important risk factors for the development of cognitive deterioration and dementia. The objective of this research was to investigate the effects of an exercise intervention on cognitive function in older T2DM patients.

Methods

Eight literature databases (PubMed, EBSCO, Scopus, Embase, The Cochrane Library, Web of Science, Ovid, and ProQuest) were searched from inception to 20 January 2022. The researchers examined randomized controlled trials (RCTs) that evaluated the impact of exercise on the cognitive performance of older T2DM patients. The Cochrane risk-of-bias tool (ROB 2) for RCTs was used to assess each study. The quality of evidence was assessed using the GRADE (grading of recommendations, assessment, development, and evaluations) approach. The mini-mental state examination (MMSE), Modified MMSE (3MSE), and Montreal cognitive assessment (MoCA) were used to evaluate the cognitive outcomes. We performed a subgroup analysis with stratification according to exercise intervention modality, duration, and cognitive impairment.

Results

Five trials were eligible, with a total of 738 T2DM patients. The combined findings revealed that exercise improved global cognitive function significantly (standardized mean difference: 1.34, 95% confidence interval: 0.23–2.44, p < 0.01). The effect of exercise on global cognitive performance was not significantly influenced by intervention modality, intervention duration, or cognitive impairment in the sub-group analysis (p > 0.05). In the studies that were included, no relevant adverse events were reported.

Conclusion

Exercise is beneficial in improving global cognitive function in older adults with T2DM. Studies with bigger sample sizes and higher quality are additionally expected to draw more definite conclusions.

Systematic Review Registration

[https://www.crd.york.ac.uk/PROSPERO/#recordDetails], identifier [CRD42022296049].

Potential of prevention strategies for the modifiable risk factor type 2 diabetes with relation to the future number of dementia patients in Germany- a multi-state projection through 2040

BACKGROUND

We assess the impact of prevention strategies regarding type 2 diabetes as a modifiable risk factor for dementia and its consequences for the future number of dementia patients in Germany.

METHODS

We used a random sample of health claims data (N = 250,000) of insured persons aged 50+ drawn in 2014, and data on population size and death rates in 2015 from the Human Mortality Database. Using exponential hazard models, we calculated age- and sex-specific transition probabilities and death rates between the states (no diabetes/no dementia, diabetes/no dementia, no diabetes/dementia, diabetes/dementia). In multi-state projections, we estimated the future number of dementia cases aged 75+ through 2040 depending on the development of the incidence of diabetes among persons without diabetes and without dementia, and the dementia incidence among persons with and without diabetes.

RESULTS

In 2015 there were 1.53 million people with dementia aged 75+ in Germany. A relative annual reduction in death rates of 2.5% and in dementia incidence in persons without diabetes of 1% will increase this number to 3.38 million by 2040. A relative reduction of diabetes incidence by 1% annually would decrease dementia cases by around 30,000, while a reduction of dementia incidence among people with diabetes by 1% would result in 220,000 fewer dementia cases. Both prevention strategies combined would prevent 240,000 dementia cases in 2040.

CONCLUSIONS

The increase in life expectancy is decisive for the future number of people with dementia. Strategies of better diabetes treatment have the potential to lower the increase in the number of dementia patients in the coming decades.

Diagnosis of TCM symptoms and analysis of risk factors of mild cognitive impairment in patients with type 2 diabetes mellitus

OBJECTIVE

To explore the diagnosis of traditional Chinese medicine (TCM) syndrome and analyze the risk factors of mild cognitive impairment (MCI) in patients with type 2 diabetes mellitus (T2DM).

METHODS

141 T2DM patients, who were hospitalized in department of endocrinology of our hospital from February 2020 to December 2020, were chosen as research subjects. The patients were divided into an observation group (n=65, T2DM with MCI) and a control group (n=76, T2DM with normal cognitive function) according to the Montreal Cognitive Assessment (MoCA) score and diagnostic criteria of MCI. Pearson correlation analysis was used to study the correlation between MoCA score and influencing factors, and multiple logistic regression analyses were applied to analyze the risk factors of T2DM patients.

RESULTS

Deficiency of kidney essence (34/65, 52.31%) and phlegm obstructing orifices (16/65, 2.62%) were common in T2DM patients with MCI. The observation group had apparently lower MoCA scores than the control group (23.46±3.12 points vs. 27.39±2.56 points, t=8.2150, P=0.0000). According to the results of multivariate logistic regression analysis, age, course of diabetes, homocysteine (HCY) and glycosylated hemoglobin (HbAlc) were the independent risk factors of MCI, and the education level was a protective factor.

CONCLUSION

Mental deficiency and phlegm obstruction are common in T2DM patients complicated with MCI. The factors such as age, diabetes course, education degree, HCY and HbAlc are closely related to MCI. The occurrence of MCI in T2DM patients can be prevented by improving the education degree of patients, effective control of blood glucose and reduction of HCY level.

Multidomain interventions: state-of-the-art and future directions for protocols to implement precision dementia risk reduction. A user manual for Brain Health Services-part 4 of 6

Although prevention of dementia and late-life cognitive decline is a major public health priority, there are currently no generally established prevention strategies or operational models for implementing such strategies into practice. This article is a narrative review of available evidence from multidomain dementia prevention trials targeting several risk factors and disease mechanisms simultaneously, in individuals without dementia at baseline. Based on the findings, we formulate recommendations for implementing precision risk reduction strategies into new services called Brain Health Services. A literature search was conducted using medical databases (MEDLINE via PubMed and SCOPUS) to select relevant studies: non-pharmacological multidomain interventions (i.e., combining two or more intervention domains), target population including individuals without dementia, and primary outcomes including cognitive/functional performance changes and/or incident cognitive impairment or dementia. Further literature searches covered the following topics: sub-group analyses assessing potential modifiers for the intervention effect on cognition in the multidomain prevention trials, dementia risk scores used as surrogate outcomes in multidomain prevention trials, dementia risk scores in relation to brain pathology markers, and cardiovascular risk scores in relation to dementia. Multidomain intervention studies conducted so far appear to have mixed results and substantial variability in target populations, format and intensity of interventions, choice of control conditions, and outcome measures. Most trials were conducted in high-income countries. The differences in design between the larger, longer-term trials that met vs. did not meet their primary outcomes suggest that multidomain intervention effectiveness may be dependent on a precision prevention approach, i.e., successfully identifying the at-risk groups who are most likely to benefit. One such successful trial has already developed an operational model for implementing the intervention into practice. Evidence on the efficacy of risk reduction interventions is promising, but not yet conclusive. More long-term multidomain randomized controlled trials are needed to fill the current evidence gaps, especially concerning low- and middle-income countries and integration of dementia prevention with existing cerebrovascular prevention programs. A precision risk reduction approach may be most effective for dementia prevention. Such an approach could be implemented in Brain Health Services.

Effects of physical exercise on memory in type 2 diabetes: a brief review

Type 2 diabetes (T2D) is a metabolic disorder that can lead to memory impairment. T2D main features are insulin resistance and hyperglycemia. Physical exercise is a non-pharmacological intervention that can regulate glycemic levels and fight insulin resistance in T2D, but whether it influences memory has been discussed. There are 2 main types of physical exercise: aerobic exercise and resistance exercise. Here, we review about the consequences of different physical exercise protocols on memory in diabetic subjects and animal models of T2D. Physical exercise, aerobic or resistance training, most of the times, is a capable agent to prevent and treat memory loss on diabetic subjects and animal models of T2D. However, whether aerobic and resistance training combined improve memory in subjects with T2D remains controversial. Regarding animal models of T2D, aerobic and resistance training have been showed to be capable to prevent and treat memory loss. Acute and chronic protocols of exercise, generally, induce positive physiological responses and adaptations in T2D, such as a better glucose control. The ideal physical exercise protocol that will produce the best benefits to diabetic subjects and to animal models of T2D has not been described yet. A variety of combination between intensity, volume, frequency, and duration of the physical exercise protocol on future studies is necessary to both diabetic subjects and animal models of T2D to determine the best protocol that will induce more benefits on memory in T2D.

Physical Activity in Early- and Mid-Adulthood Are Independently Associated With Longitudinal Memory Trajectories in Later Life

BACKGROUND

Physical activity (PA) in later life may reduce dementia risk, but little is known regarding long-term cognitive effects of PA that occurred earlier in adulthood or mechanisms underlying associations. PA patterns at different ages may independently contribute to dementia risk, which would implicate multiple critical periods for intervention. The current study tested whether retrospective reports of PA in early and mid-adulthood were independently associated with later-life longitudinal memory outcomes and whether associations were mediated by late-life cardiometabolic diseases.

METHOD

Participants comprised 5200 Health and Retirement Study Life History Mail Survey respondents. Latent growth curves estimated independent associations between retrospectively reported PA in early adulthood (age 18-29) and mid-adulthood (age 40-49) and 16-year episodic memory trajectories. Indirect pathways involving the maintenance of PA from early- to mid-adulthood and the influence of PA on later-life cardiometabolic diseases (hypertension, diabetes, and heart disease) were also estimated.

RESULTS

PA in early- and mid-adulthood independently predicted higher initial memory level and slower memory decline in later life, respectively. Early-adulthood PA was indirectly associated with later-life memory level through higher mid-adulthood PA and lower rates of later-life hypertension, as well as with subsequent memory decline through higher mid-adulthood PA.

CONCLUSIONS

The current findings highlight the importance of PA throughout adulthood, such that initiating and/or maintaining exercise in early- or mid-adulthood may be protective for later-life cognitive health, and hypertension appears to represent a key mediator of these effects.

The Multi-Domain Intervention Trial in Older Adults With Diabetes Mellitus for Prevention of Dementia in Japan: Study Protocol for a Multi-Center, Randomized, 18-Month Controlled Trial

Background: The Japan-Multi-domain Intervention Trial for Prevention of Dementia in Older Adults with Diabetes (J-MIND-Diabetes) is an 18-month, multi-centered, open-labeled, randomized controlled trial designed to identify whether multi-domain intervention targeting modifiable risk factors for dementia could prevent the progression of cognitive decline among older adults with type 2 diabetes mellitus (T2DM). This manuscript describes the study protocol for the J-MIND-Diabetes trial. Materials and Methods: Subjects of this trial will comprise a total of 300 T2DM outpatients aged 70-85 years with mild cognitive impairment. Subjects will be centrally randomized into intervention and control groups at a 1:1 allocation ratio using the stratified permuted-block randomization methods. The intervention group will participate in multi-domain intervention programs aimed at: (1) management of metabolic and vascular risk factors; (2) physical exercise and self-monitoring of physical activity; (3) nutritional guidance; and (4) social participation. The control group will receive usual T2DM care and general instructions on dementia prevention. The primary and secondary outcomes will be assessed at baseline, at 6- and 18-month follow-up. The primary outcome is change from baseline at 18 months in a global composite score combining several neuropsychological domains, including global cognitive function, memory, attention, executive function, processing speed and language. Secondary outcomes include: (1) cognitive changes in neuropsychological tests; (2) changes in geriatrics assessments; (3) metabolic control and diabetic complications; (4) changes in blood and urinary markers. Discussion: This trial will be the first trial to demonstrate the effectiveness of multi-domain intervention in preventing cognitive decline in older adults with T2DM at increased risk of dementia in Japan. Trial Registration: UMIN000035911; Registered on the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) 18 February 2019. (https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000040908).

Exercise Improves Cognitive Function-A Randomized Trial on the Effects of Physical Activity on Cognition in Type 2 Diabetes Patients

Background: Lifestyle habits strongly influence health. It is strongly believed that physical activity may improve cognitive function. We examined the association between two kinds of physical activity and cognitive function in patients with type 2 diabetes. Methods: Using a random allocation sequence, 49 patients with type 2 diabetes (metformin, insulin, and diet-controlled) were randomized to a 12-week intervention of either walking 40 min three times a week (n = 17), performing pedometer-controlled activity (E-health, goal 10,000 steps a day, n = 17), or receiving standard care (n = 16 controls). We prospectively examined cognitive function, metabolic parameters, height, and weight. The groups were compared using linear regression adjusted for age. Results: Compared with the control group (n = 16), nonverbal memory improved significantly after the intervention in the walking group (n = 16) (28.2 (+/−6.1) vs. 35.3 (+/−5.3) p < 0.001) and the E-health (pedometer) group ((n = 17) (29.7 (+/−3.9) vs. 35.6 (+/−3.8) p < 0.001). The verbal memory test showed improvement in the walking and E-health groups. Cognitive attention/performance measured by the FAIR-test was also significantly enhanced in the walking group (252.4/304.3 p < 0.001, 51.87 (CI 27.13–76.62)) and the E-health-group (85.65 (CI: 52.04–119.26, p < 0.001)). Abdominal circumference (−3 cm (CI: −9.69–3.31, p < 0.001)), heart rate (−6.50 (CI: −9.69, −3.31, p < 0.001)) and fat percentage (−2.74 (CI: −4.71, −0.76, p < 0.007)) changed significantly in only the walking group. Conclusions: This is the first intervention study in patients with type 2 diabetes that shows that pedometer-supported training significantly improves brain function. Walking additionally improves body composition and waist circumference. Physical activity is an inexpensive treatment with substantial preventative and restorative properties for cognitive and memory brain function in patients with type 2 diabetes.

Effects of physical-cognitive training on physical and psychological functions among older adults with type 2 diabetes and balance impairment: a randomized controlled trial

Risks of falls among older adults are multifactorial in nature. A combined training program might be beneficial on fall-related outcomes. This study aimed to explore the effects of group-based physical-cognitive trainings on physical and psychological outcomes among older adults with type 2 diabetes mellitus (T2DM) and balance impairment. Fall incidence were also determined. Thirty-seven older adults with T2DM and balance impairment were randomly assigned to control and intervention groups. The intervention program comprised of 24 training sessions of 45–60 min exercise for 8 weeks. The exercise consisted of warm-up, aerobic exercise by nine square stepping, resistance exercise combined with cognitive training and cool down. All participants were assessed at baseline, 4 and 8 weeks after intervention, and 1-year follow-up. Both groups reported similar rates of falls. Global cognition, depressive symptoms, and fear of falling did not differ between groups at any time. The Timed Up & Go (TUG) test, alternate stepping test (AST), knee extensors, ankle plantarflexors, and dorsiflexors strength differed at 4 weeks. TUG, AST, hip abductors, knee flexors, ankle plantarflexors, and dorsiflexors strength differed at 8 weeks. The activity of daily living (ADL), TUG test (P=0.002) and AST, hip extensors and abductors, knee extensors and flexors, ankle plantarflexors and dorsiflexors were different at 1-year follow-up. The group-based physical-cognitive training could benefit older adults with T2DM in terms of maintaining ADL. The intervention could reduce fall risk factors by improving balance and lower limb muscle strength among older adults with T2DM and balance impairment.

Metabolic syndrome and the benefit of a physical activity intervention on lower-extremity function: Results from a randomized clinical trial

BACKGROUND

In older adults, increases in physical activity may prevent decline in lower-extremity function, but whether the benefit differs according to metabolic syndrome (MetS) status is uncertain. We aim to investigate whether structured physical activity is associated with less decline in lower-extremity function among older adults with versus without MetS.

METHODS

We used data from the multicenter Lifestyle Interventions and Independence for Elders (LIFE) study to analyze 1535 sedentary functionally-vulnerable women and men, aged 70 to 89 years old, assessed every 6 months (February 2010-December 2013) for an average of 2.7 years. Participants were randomized to a structured, moderate-intensity physical activity intervention (PA; n = 766) or health education program (HE; n = 769). MetS was defined according to the 2009 multi-agency harmonized criteria. Lower-extremity function was assessed by 400-m walking speed and the Short Physical Performance Battery (SPPB) score.

RESULTS

763 (49.7%) participants met criteria for MetS at baseline. Relative to HE, PA was associated with faster 400-m walking speed among participants with MetS (P < 0.001) but not among those without MetS (P = 0.91), although the test for statistical interaction was marginally non-significant (P = 0.07). In contrast, no benefit of PA versus HE was observed on the SPPB score in either MetS subgroup.

CONCLUSIONS

Among older adults at high risk for mobility disability, moderate-intensity physical activity conveys significant benefits in 400-m walking speed but not SPPB in those with, but not without, MetS. The LIFE physical activity program may be an effective strategy for maintaining or improving walking speed among vulnerable older adults with MetS.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01072500.

Effects of physical activity on cognitive function among patients with diabetes in China: a nationally longitudinal study

Background

We aimed to examine the effect of physical activity on different cognitive domains among patients with diabetes.

Methods

We used two waves of data from the Chinese Health and Retirement Longitudinal Study (CHARLS, 2013–2015), a nationally representative dataset of Chinese population aged over 45. Total physical activity scores were calculated based on the International Physical Activity Questionnaire (IPAQ). Executive function and episodic memory were used as measures of cognitive function. We conducted lagged dependent variable models to explore the association between physical activity and cognitive function in full sample as well as two different age groups (45–65, ≥65). Results: 862 diabetic patients were included. We found that diabetic participants who had greater level of physical activity at baseline were associated with better episodic memory function in 2 years (p < 0.05). Moreover, physical activity was significantly associated with less decline in episodic memory in fully adjusted models, and the associations were stronger among patients aged 45–65 years (p < 0.05). No statistically significant association was found between physical activity and executive function in all age groups.

Conclusions

Physical activity may prevent some of the potential decline in episodic memory in diabetic patients. Clinicians and public health departments should strengthen the promotion of physical activity and develop early screening tools among diabetic participants to prevent the progression of cognitive impairment.

Exercise-Linked Irisin: Consequences on Mental and Cardiovascular Health in Type 2 Diabetes

Type 2 diabetes mellitus (T2DM) is a metabolic disorder associated with insulin resistance and hyperglycemia. Chronic exposure to a T2DM microenvironment with hyperglycemia, hyperinsulinemia, oxidative stress and increased levels of proinflammatory mediators, has negative consequences to the cardiovascular system and mental health. Therefore, atherosclerotic cardiovascular diseases (CVD) and mental health issues have been strongly associated with T2DM. Lifestyle modifications, including physical exercise training, are necessary to prevent T2DM development and its associated complications. It is widely known that the regular practice of exercise provides several physiological benefits to subjects with T2DM, such as managing glycemic and blood pressure levels. Different types of exercise, from aerobic to resistance training, are effective to improve mental health and cognitive function in T2DM. Irisin is a myokine produced in response to exercise, which has been pointed as a relevant mechanism of action to explain the benefits of exercise on cardiovascular and mental health in T2DM patients. Here, we review emerging clinical and experimental evidence about exercise-linked irisin consequences to cardiovascular and mental health in T2DM.

The Benefits of Physical Activity in Individuals with Cardiovascular Risk Factors: A Longitudinal Investigation Using fNIRS and Dual-Task Walking

Cardiovascular fitness is linked to better executive functions, preserved gait speed, and efficient cortical activity. Older adults with cardiovascular risk factors (CVRFs) typically show poor cognitive performance, low physical fitness, and altered brain functioning compared with healthy individuals. In the current study, the impact of regular physical activity on cognition, locomotion, and brain functions was explored in a cohort of older adults with low or high CVRFs. Cortical activation of the frontal areas was investigated using functional Near-Infrared Spectroscopy (fNIRS) at baseline, at 6 months and at 12 months. Evoked cortical response and behavioral performance were assessed using the dual-task walking paradigm, consisting of three conditions: single cognitive task (2-back task), single walking task (walking), and dual-task (2-back whilst walking). Results show greater task-related cortical response at baseline in individuals with high CVRFs compared to those with low CVRFs. Moreover, participants with high CVRFs benefitted the most from participating in regular physical activity, as their cortical response decreased at the 12-month follow-up and became comparable to that of participants with low CVRFs. These changes were observed in conjunction with improved cognitive performance and stable gait speed throughout the 12-month period in both groups. Our findings provide evidence that participation in regular physical activity may be especially beneficial in individuals with CVRFs by promoting brain and cognitive health, thus potentially contributing to prevention of cognitive decline. Future research may explore whether such effects are maintained in the long-term in order to design ad-hoc interventions in this specific population.

Obesity-induced cognitive impairment in older adults: a microvascular perspective

Over two-thirds of individuals aged 65 and older are obese or overweight in the United States. Epidemiological data show an association between the degree of adiposity and cognitive dysfunction in the elderly. In this review, the pathophysiological roles of microvascular mechanisms, including impaired endothelial function and neurovascular coupling responses, microvascular rarefaction, and blood-brain barrier disruption in the genesis of cognitive impairment in geriatric obesity are considered. The potential contribution of adipose-derived factors and fundamental cellular and molecular mechanisms of senescence to exacerbated obesity-induced cerebromicrovascular impairment and cognitive decline in aging are discussed.

Impact of Diet and Exercise on Weight and Cognition in Older Adults: A Rapid Review

OBJECTIVE

To determine where the current literature stands in regard to diet/exercise interventions on cognition in overweight or obese individuals.

DATA SOURCE

A rapid review was conducted of English-language studies published in Medline from January 1965 to January 2020.

STUDY INCLUSION AND EXCLUSION CRITERIA

Included studies were intervention studies lasting ≥12 weeks, with participants aged ≥65 years, with a body mass index ≥25 kg/m².

DATA EXTRACTION

Data extracted included study population, duration, intervention design, outcomes, and results.

DATA SYNTHESIS

Outcomes were qualitatively measured due to paucity of RTC.

RESULTS

1845 citations were identified, 31 full-text articles were reviewed, and 5 studies were included. Studies had usual care control groups and combined exercise/diet intervention groups with 31-3,526 participants randomized to each arm. Mean age of participants was 69.2-83.4 years. Studies reporting on cognitive changes showed marginally significant positive changes in cognition, and those that reported BMI indicated potential improvements in cognition.

CONCLUSIONS

The number of interventions assessing the combined effects of both diet and exercise is low. Future studies should evaluate the impact of combined effects to ascertain whether cognitive decline may be reversed in older adults with a BMI ≥25 kg/m².

Long-term Change in Physiological Markers and Cognitive Performance in Type 2 Diabetes: The Look AHEAD Study

CONTEXT

The effects of physiological improvements on cognitive function among persons with type 2 diabetes mellitus (T2DM) are not fully understood.

OBJECTIVE

To determine whether improvements in physiological markers (body weight, blood sugar control, and physical activity) during intensive lifestyle intervention (ILI) are associated with enhancements in cognitive function in older adults with T2DM.

DESIGN

Multisite randomized controlled trial.

SETTING

Academic research centers.

PATIENTS OR OTHER PARTICIPANTS

Participants were aged 45-76 years, with T2DM.

INTERVENTION

The Action for Health in Diabetes (Look AHEAD) study, a randomized, controlled clinical trial of ILI.

MAIN OUTCOME MEASURE

Two to 3 cognitive assessments were collected from 1089 participants, the first and last occurring a mean (standard deviation) of 8.6 (1.0) and 11.5 (0.7) years after enrollment.

RESULTS

Greater improvement in blood sugar control was associated with better cognitive scores (fasting glucose and Rey Auditory Verbal Learning Test [AVLT]: P = 0.0148; fasting glucose and Digit Symbol Coding (DSC): P = 0.0360; HbA1C and DSC: P = 0.0477); but weight loss had mixed associations with cognitive scores (greater body mass index [BMI] reduction and worse AVLT overall: P = 0.0053; and greater BMI reduction and better DSC scores among those overweight but not obese at baseline: P = 0.010). Associations were strongest among those who were overweight (not obese) at baseline, and among those with a history of cardiovascular disease (CVD) at baseline.

CONCLUSIONS

Improvements in glycemic control, but not necessarily weight status, during ILI may be associated with better subsequent cognitive performance. These associations may differ by adiposity and CVD history.

High-sugar diet intake, physical activity, and gut microbiota crosstalk: Implications for obesity in rats

This study aims to evaluate the effect of long-term high-sugar diet (HSD) intake and regular physical activity on gut microbiota as well as its health impact. Weaned male Wistar rats were fed with standard chow diet (SSD) or HSD ad libitum and subjected or not to regular swimming training with a workload (2% of body weight) for 15 weeks. Feces samples were used on microbiome analysis using 16S rRNA amplicon sequencing. HSD increased body mass, adipose cushions, and the serum levels of triglycerides and VLDL, also changed the bacteria taxons associated with metabolic disorders (increase taxons belonging to Proteobacteria phylum and decrease Pediococcus genus); the swim training reverted these changes. SSD intake increased the abundance of bacteria associated with metabolization of dietary fiber. Training in association with SSD consumption beneficially modulated the microbiota, increasing the Bacteroidetes, Bacteroidaceae, Porphyromonadaceae, Parabacteroides, and Lactobacillaceae, and decreasing the Firmicute/Bacteroidetes ratio; training was not able to maintain this profile in animals SHD-fed. Physical training modulates the gut microbiota reversing the obesogenic response caused by SHD. However, training itself is not efficient for up-regulating the probiotic bacteria in comparison to its association with a balanced diet.

The Potential Mediation of the Effects of Physical Activity on Cognitive Function by the Gut Microbiome

The population of older adults is growing dramatically worldwide. As older adults are at greater risk of developing disorders associated with cognitive dysfunction (i.e., dementia), healthcare costs are expected to double by 2040. Evidence suggests dementia may be slowed or prevented by lifestyle interventions, including physical activity (PA). PA is associated with improved cognitive function and may reduce risk for dementia by mitigating known risk factors (i.e., cardiovascular diseases) and/or by enhancing neurochemical processes. An emerging area of research suggests the gut microbiome may have similar neuroprotective effects. Altering the gut microbiome has been found to target physiological processes associated with dementia risk, and it influences gut-brain-microbiome axis signaling, impacting cognitive functioning. The gut microbiome can be altered by several means (i.e., disease, diet, prebiotics, probiotics), including PA. As PA and the gut microbiome independently influence cognitive function and PA changes the composition of the gut microbiome, cognitive improvement due to PA may be partially mediated by the gut microbiome. The present article provides an overview of the literature regarding the complex associations among PA, cognitive function, and the gut microbiome, as well as their underlying biological mechanisms. A comprehensive, theoretical model integrating evidence for the potential mediation is proposed.

Changes in Cognitive Function and in the Levels of Glycosylated Haemoglobin (HbA1c) in Older Women with Type 2 Diabetes Mellitus Subjected to a Cardiorespiratory Exercise Programme

Ageing and diabetes are recognised as important risk factors for the development of cognitive deterioration. The aim was to analyse the effects of a walking-based training programme on cognitive deterioration and glycosylated haemoglobin (HbA1c) in older women with type 2 diabetes. This was a six-month experimental and longitudinal study with an experimental group (EG) (n = 57) and a control group (CG) (n = 52). All participants were diabetic with hypoglycaemic treatment. EG carried out a walking-based training program. After the training, we evaluated the diabetic state (HbA1c), cognitive functioning with the Mini-Mental State Examination (MMSE), cardiorespiratory fitness (VO2max) and body mass index (BMI). Results: EG obtained better results than CG in all the analysed variables. EG showed a significant improvement in the levels of HbA1c (−4.5%; p < 0.001), VO2max (+5.9%; p < 0.001) and BMI (−5.4%; p < 0.001); it also obtained increases in the scores of cognitive functioning, which were statistically significant in all dimensions, except for calculation (p = 0.384) and language (p = 0.168). Conclusion: The aerobic treatment produced significant improvements in the diabetic state and cognitive functioning in older women with type 2 diabetes.

Effectiveness of A Pilates Training Program on Cognitive and Functional Abilities in Postmenopausal Women

The purpose of this study was to determine the effects of a Pilates exercises program on the cognitive and physical functioning of older Spanish women. This study is a randomized clinical trial; a total of 110 women aged ≥60 years were initially allocated to either a Pilates group (PG, n = 55), who underwent a 12-week Pilates exercise program, or to a control group (CG, n = 55), who did not receive any intervention. Global cognitive function (Mini-Mental State Examination), verbal fluency (Isaacs test), executive function (Trail Making Test), functional flexibility (Back Scratch Test and Chair Sit-and-Reach Test), and lower-body strength (30 s Chair-Stand Test) were assessed before and immediately after the intervention period. The main findings of this study suggest that women in the PG (within-group differences) experienced improvements across all the variables examined except for global cognitive function. When compared with the CG (between-group differences), our analysis revealed significant benefits in the PG for all measures except for global cognitive function and functional flexibility (Back Scratch Test). In conclusion, our results suggest that Pilates has the potential to improve both cognitive and functional abilities among Spanish women aged 60 years and over.

Effects of exercise, cognitive, and dual-task interventions on cognition in type 2 diabetes mellitus: A systematic review and meta-analysis

Introduction

Previous evidence has shown significant effects of exercise, cognitive and dual-task training for improving cognition in healthy cohorts. The effects of these types of interventions in type 2 diabetes mellitus is unclear. The aim of this research was to systematically review evidence, and estimate the effect, of exercise, cognitive, and dual-task interventions on cognition in type 2 diabetes mellitus.

Method

Electronic databases including PubMed, EMBASE, CINAHL, PsycINFO, SPORTDiscus, and MEDLINE were searched for ongoing and completed interventional trials investigating the effect of either an exercise, cognitive or dual-task intervention on cognition in type 2 diabetes mellitus.

Results

Nine trials met the inclusion criteria–one dual-task, two cognitive, and six exercise. Meta-analyses of exercise trials showed no significant effects of exercise on measures of executive function (Stroop task, SMD = -0.31, 95% CI -0.71–0.09, P = 0.13, trail making test part A SMD = 0.28, 95% CI -0.20–0.77 P = 0.25, trail making test part B SMD = -0.15, 95% CI -0.64–0.34 P = 0.54, digit symbol SMD = 0.09, 95% CI -0.39–0.57 P = 0.72), and memory (immediate memory SMD = 0.20, 95% CI -0.28–0.69, P = 0.41 and delayed memory SMD = -0.06, 95% CI -0.55–0.42, P = 0.80). A meta-analysis could not be conducted using cognitive or dual-task data, but individual trials did report a favourable effect of interventions on cognition. Risk of bias was considered moderate to high for the majority of included trials.

Conclusions

Meta-analyses of exercise trials identified a small effect size (0.31), which whilst not significant warrants further investigation. Larger and more robust trials are needed that report evidence using appropriate reporting guidelines (e.g. CONSORT) to increase confidence in the validity of results.

Trial registration

Protocol was registered (CRD42017058526) on the International Prospective Register of Systematic Reviews (http://www.crd.york.ac.uk/PROSPERO).

Effectiveness of a community program for older adults with type 2 diabetes and multimorbidity: a pragmatic randomized controlled trial

BACKGROUND

Type II diabetes mellitus (T2DM) affects upwards of 25% of Canadian older adults and is associated with high comorbidity and burden. Studies show that lifestyle factors and self-management are associated with improved health outcomes, but many studies lack rigour or exclude older adults, particularly those with multimorbidity. More evidence is needed on the effectiveness of community-based self-management programs in older adults with T2DM and multimorbidity. The study purpose is to evaluate the effect of a community-based intervention versus usual care on physical functioning, mental health, depressive symptoms, anxiety, self-efficacy, self-management, and healthcare costs in older adults with T2DM and 2 or more comorbidities.

METHODS

Community-living older adults with T2DM and two or more chronic conditions were recruited from three Primary Care Networks (PCNs) in Alberta, Canada. Participants were randomly allocated to the intervention or control group in this pragmatic randomized controlled trial comparing the intervention to usual care. The intervention involved up to three in-home visits, a monthly group wellness program, monthly case conferencing, and care coordination. The primary outcome was physical functioning. Secondary outcomes included mental functioning, anxiety, depressive symptoms, self-efficacy, self-management, and the cost of healthcare service use. Intention-to-treat analysis was performed using ANCOVA modeling.

RESULTS

Of 132 enrolled participants (70-Intervention, 62-Control), 42% were 75 years or older, 55% were female, and over 75% had at least six chronic conditions (in addition to T2DM). No significant group differences were seen for the baseline to six-month change in physical functioning (mean difference: -0.74; 95% CI: - 3.22, 1.74; p-value: 0.56), mental functioning (mean difference: 1.24; 95% CI: - 1.12, 3.60; p-value: 0.30), or other secondary outcomes..

CONCLUSION

No significant group differences were seen for the primary outcome, physical functioning (PCS). Program implementation, baseline differences between study arms and chronic disease management services that are part of usual care may have contributed to the modest study results. Fruitful areas for future research include capturing clinical outcome measures and exploring the impact of varying the type and intensity of key intervention components such as exercise and diet.

TRIAL REGISTRATION

NCT02158741 Date of registration: June 9, 2014.

Pathways of Prevention: A Scoping Review of Dietary and Exercise Interventions for Neurocognition

Alzheimer's disease and related dementias (ADRD) represent an increasingly urgent public health concern, with an increasing number of baby boomers now at risk. Due to a lack of efficacious therapies among symptomatic older adults, an increasing emphasis has been placed on preventive measures that can curb or even prevent ADRD development among middle-aged adults. Lifestyle modification using aerobic exercise and dietary modification represents one of the primary treatment modalities used to mitigate ADRD risk, with an increasing number of trials demonstrating that exercise and dietary change, individually and together, improve neurocognitive performance among middle-aged and older adults. Despite several optimistic findings, examination of treatment changes across lifestyle interventions reveals a variable pattern of improvements, with large individual differences across trials. The present review attempts to synthesize available literature linking lifestyle modification to neurocognitive changes, outline putative mechanisms of treatment improvement, and discuss discrepant trial findings. In addition, previous mechanistic assumptions linking lifestyle to neurocognition are discussed, with a focus on potential solutions to improve our understanding of individual neurocognitive differences in response to lifestyle modification. Specific recommendations include integration of contemporary causal inference approaches for analyzing parallel mechanistic pathways and treatment-exposure interactions. Methodological recommendations include trial multiphase optimization strategy (MOST) design approaches that leverage individual differences for improved treatment outcomes.

Obesity-related cognitive impairment: The role of endothelial dysfunction

Obesity is a global pandemic associated with macro- and microvascular endothelial dysfunction. Microvascular endothelial dysfunction has recently emerged as a significant risk factor for the development of cognitive impairment. In this review, we present evidence from clinical and preclinical studies supporting a role for obesity in cognitive impairment. Next, we discuss how obesity-related hyperinsulinemia/insulin resistance, systemic inflammation, and gut dysbiosis lead to cognitive impairment through induction of endothelial dysfunction and disruption of the blood brain barrier. Finally, we outline the potential clinical utility of dietary interventions, exercise, and bariatric surgery in circumventing the impacts of obesity on cognitive function.

Dietary Protein, Exercise, and Frailty Domains

Increasing awareness of the impact of frailty on elderly people resulted in research focusing on factors that contribute to the development and persistence of frailty including nutrition and physical activity. Most effort so far has been spent on understanding the association between protein intake and the physical domain of frailty. Far less is known for other domains of frailty: cognition, mood, social health and comorbidity. Therefore, in the present narrative review, we elaborate on the evidence currently known on the association between protein and exercise as well as the broader concept of frailty. Most, but not all, identified studies concluded that low protein intake is associated with a higher prevalence and incidence of physical frailty. Far less is known on the broader concept of frailty. The few studies that do look into this association find a clear beneficial effect of physical activity but no conclusions regarding protein intake can be made yet. Similar, for other important aspects of frailty including mood, cognition, and comorbidity, the number of studies are limited and results are inconclusive. Future studies need to focus on the relation between dietary protein and the broader concept of frailty and should also consider the protein source, amount and timing.

Impact of a Multidomain Intensive Lifestyle Intervention on Complaints About Memory, Problem-Solving, and Decision-Making Abilities: The Action for Health in Diabetes Randomized Controlled Clinical Trial

Background

Lifestyle interventions to reduce weight and increase activity may preserve higher-order cognitive abilities in overweight/obese adults with type 2 diabetes (T2D).

Methods

Adults (N = 5,084) with T2D who enrolled in a randomized clinical trial of a 10-year intensive lifestyle intervention (ILI) compared with diabetes support and education were queried at baseline and repeatedly during follow-up for complaints about difficulties in memory, problem-solving, and decision-making abilities.

Results

For those without baseline complaints, assignment to ILI was associated with lower odds that complaints would emerge during follow-up for decision-making ability (odds ratio [OR]=0.851, [95% CI, 0.748,0.967], p=0.014), and, among individuals who were not obese, lower odds that complaints would emerge about problem-solving ability (OR=0.694 [0.510,0.946]). No cognitive benefits from ILI were seen for individuals with baseline complaints about cognitive abilities. ILI may have exacerbated the severity of complaints about problem-solving ability during follow-up among individuals with baseline complaints and cardiovascular disease (OR=2.949 [1.378,6.311]).

Conclusions

A long-term multidomain ILI may reduce the likelihood that complaints about difficulties in higher-order cognitive abilities will emerge in T2D adults without pre-existing complaints. Among those with pre-existing complaints, the ILI did not prevent increases in complaint severity.

Qualitative neurological gait abnormalities, cardiovascular risk factors and functional status in older community-dwellers without neurological diseases: The Healthy Brain Project

BACKGROUND

Neurologic gait abnormalities (NGA) increase risk for falls and dementia, but their pathophysiologic substrates or association with disability have been poorly investigated. We evaluated the association of NGA with clinical characteristics and functional status in older community-dwellers.

METHODS

Gait characteristics were measured in older community-dwellers without neurological or psychological diseases participating to the Health Aging Body Composition study. NGA were rated using standardized readings of video-recorded short walks, combined with standard neurological exam. We tested cross-sectional associations with demographics, vascular risk factors, comorbidities, cognitive function and disability.

RESULTS

Of 177 participants (median age [IQR] = 82 [4] years, 55% women, 58% Caucasian), 49 (27.7%) had NGA. The most prevalent sub-types were unsteady (10.7%), hemiparetic (4.5%) and parkinsonian (4%). In multivariable logistic regression models, diabetes was associated with higher risk (OR = 3.24, 95% CI = 1.38-7.59), whereas higher physical activity (OR = 0.89, 95% CI = 0.80-0.99) and gait speed (OR = 0.04, 95% CI = 0.005-0.27) with lower risk of NGA. Prevalence of NGA was associated with difficulty in at least 1 activity of daily living, adjusting for confounders (OR = 2.90, 95% CI = 1.11-7.58). After adjusting for gait speed, this association was attenuated to non-significance (OR = 2.13, 95% CI = 0.71-6.37).

CONCLUSIONS

In our sample of community-dwelling older adults without neurological diseases, NGA, detected with a standardized neurological exam, part of usual physicians' training, were common. The relationships with diabetes and reduced physical activity might suggest vascular dysfunction as an underlying contributor to NGA. These results, if confirmed by longitudinal studies, which should also disentangle the relationship between NGA, gait speed and disability, might add information for preventing and managing mobility disability.

Long-term Impact of Weight Loss Intervention on Changes in Cognitive Function: Exploratory Analyses from the Action for Health in Diabetes Randomized Controlled Clinical Trial

Background

Diabetes adversely impacts cognition. Lifestyle change can improve diabetes control and potentially improve cognition. We examined whether weight loss through reduced caloric intake and increased physical activity was associated with slower cognitive aging in older adults with type 2 diabetes mellitus.

Methods

The Look AHEAD randomized controlled clinical trial delivered 10 years of intensive lifestyle intervention (ILI) that yielded long-term weight losses. During 5 years spanning the end of intervention and postintervention follow-up, repeated cognitive assessments were obtained in 1,091 individuals who had been assigned to ILI or a control condition of diabetes support and education (DSE). We compared the means and slopes of scores on cognitive testing over these repeated assessments.

Results

Compared with DSE, assignment to ILI was associated with a -0.082 SD deficit in mean global cognitive function across repeated assessments (p = .010). However, overweight (body mass index [BMI] < 30 kg/m2) ILI participants had 0.099 (95% confidence interval [CI]: -0.006, 0.259) better mean global cognitive function compared with overweight DSE participants, while obese (BMI ≥ 30 kg/m2) ILI participants had -0.117 (-0.185, -0.049) SD worse mean composite cognitive function scores (interaction p = .014) compared to obese DSE participants. For both overweight and obese participants, cognitive decline was marginally (-0.014 SD/y overall) steeper for ILI participants (p = .068), with 95% CI for differences in slopes excluding 0 for measures of attention and memory.

Conclusions

The behavioral weight loss intervention was associated with small relative deficits in cognitive function among individuals who were obese and marginally greater cognitive decline overall compared to control. ClinicalTrials.gov Identifier: NCT00017953.

Feasibility of a multi-modal exercise program on cognition in older adults with Type 2 diabetes - a pilot randomised controlled trial

BACKGROUND

Type 2 Diabetes (T2D) is associated with increased risk of dementia. We aimed to determine the feasibility of a randomised controlled trial (RCT) examining the efficacy of exercise on cognition and brain structure in people with T2D.

METHODS

A 6-month pilot parallel RCT of a progressive aerobic- and resistance-training program versus a gentle movement control group in people with T2D aged 50-75 years (n = 50) at the University of Tasmania, Australia. Assessors were blinded to group allocation. Brain volume (total, white matter, hippocampus), cortical thickness and white matter microstructure (fractional anisotrophy and mean diffusivity) were measured using magnetic resonance imaging, and cognition using a battery of neuropsychological tests. Study design was assessed by any changes (during the pilot or recommended) to the protocol, recruitment by numbers screened and time to enrol 50 participants; randomisation by similarity of characteristics in groups at baseline, adherence by exercise class attendance; safety by number and description of adverse events and retention by numbers withdrawn.

RESULTS

The mean age of participants was 66.2 (SD 4.9) years and 48% were women. There were no changes to the design during the study. A total of 114 people were screened for eligibility, with 50 participants with T2D enrolled over 8 months. Forty-seven participants (94%) completed the study (23 of 24 controls; 24 of 26 in the intervention group). Baseline characteristics were reasonably balanced between groups. Exercise class attendance was 79% for the intervention and 75% for the control group. There were 6 serious adverse events assessed as not or unlikely to be due to the intervention. Effect sizes for each outcome variable are provided.

CONCLUSION

This study supports the feasibility of a large scale RCT to test the benefits of multi-modal exercise to prevent cognitive decline in people with T2D. Design changes to the future trial are provided.

TRIAL REGISTRATION

ANZCTR 12614000222640 ; Registered 3/3/2014; First participant enrolled 26/6/2014, study screening commenced 1/9/2014; Australian and New Zealand Clinical Trial Registry.

The Associations among Insulin Resistance, Hyperglycemia, Physical Performance, Diabetes Mellitus, and Cognitive Function in Relatively Healthy Older Adults with Subtle Cognitive Dysfunction

Insulin resistance (IR), diabetes mellitus (DM), sarcopenia, and cognitive dysfunction are thought to be mutually associated. We conducted a comprehensive assessment of the relationships among IR, gait speed, hyperglycemia, and DM by cross-sectionally analyzing the baseline data of an interventional study for cognitive preservation with physical exercise (the TOyota Preventional Intervention for Cognitive decline and Sarcopenia [TOPICS]). The participants (n = 444) were relatively healthy older individuals who had mild cognitive impairment without dementia, and 61 of the participants had DM. Slow gait speed and hyperglycemia were associated with cognitive dysfunction, mainly in the executive function domain, whereas IR was associated with memory impairment. The participants with DM had lower general cognition and executive function. Executive dysfunction in the DM participants seemed to be partly explained by hyperglycemia and/or slow gait speed. Our findings confirmed that IR, DM, sarcopenia, and cognitive dysfunction are mutually associated in complex ways. Understanding the mechanisms underlying these associations will lead to effective strategies to prevent and treat cognitive dysfunction in older individuals.

Steps to Health in Cognitive Aging: Effects of Physical Activity on Spatial Attention and Executive Control in the Elderly

The purpose of this study was to investigate whether physical activity (PA) habits may positively impact performance of the orienting and executive control networks in community-dwelling aging individuals and diabetics, who are at risk of cognitive dysfunction. To this aim, we tested cross-sectionally whether age, ranging from late middle-age to old adulthood, and PA level independently or interactively predict different facets of the attentional performance. Hundred and thirty female and male individuals and 22 adults with type 2 diabetes aged 55–84 years were recruited and their daily PA (steps) was objectively measured by means of armband monitors. Participants performed a multifunctional attentional go/no-go reaction time (RT) task in which spatial attention was cued by means of informative direct cues of different sizes followed by compound stimuli with local and global target features. The performance efficiency of the orienting networks was estimated by computing RT differences between validly and invalidly cued trials, that of the executive control networks by computing local switch costs that are RT differences between switch and non-switch trials in mixed blocks of global and local target trials. In regression analyses performed on the data of non-diabetic elderlies, overall RTs and orienting effects resulted jointly predicted by age and steps. Age predicted overall RTs in low-active individuals, but orienting effects and response errors in high-active individuals. Switch costs were predicted by age only, with larger costs at older age. In the analysis conducted with the 22 diabetics and 22 matched non-diabetic elderlies, diabetic status and daily steps predicted longer and shorter RTs, respectively. Results suggest that high PA levels exert beneficial, but differentiated effects on processing speed and attentional networks performance in aging individuals that partially counteract the detrimental effects of advancing age and diabetic status. In conclusion, adequate levels of overall PA may positively impinge on brain efficiency and attentional control and should be therefore promoted by actions that support lifelong PA participation and impact the built environment to render it more conducive to PA.

Pathophysiologic relationship between Alzheimer's disease, cerebrovascular disease, and cardiovascular risk: A review and synthesis

As the population ages due to demographic trends and gains in life expectancy, the incidence and prevalence of dementia increases, and the need to understand the etiology and pathogenesis of dementia becomes ever more urgent. Alzheimer's disease (AD), the most common form of dementia, is a complex disease, the mechanisms of which are poorly understood. The more we learn about AD, the more questions are raised about our current conceptual models of disease. In the absence of a cure or the means by which to slow disease progress, it may be prudent to apply our current knowledge of the intersection between AD, cardiovascular disease, and cerebrovascular disease to foster efforts to delay or slow the onset of AD. This review discusses our current understanding of the epidemiology, genetics, and pathophysiology of AD, the intersection between AD and vascular causes of dementia, and proposes future directions for research and prevention.