Protocol of Aerobic Exercise and Cognitive Health (REACH): A Pilot Study

Leisure, Mental Health, and Life Satisfaction among Older Adults with Mild Cognitive Impairment

Objectives: Little research has investigated the relationship between types of leisure activities and mental health outcomes among older adults with mild cognitive impairment (MCI). The purpose of this study was to investigate how certain leisure activities are associated with life satisfaction, anxiety, loneliness, happiness, and positive and negative affect. Methods: In this study, we used the 2020 Health and Retirement Study Core Early data and conducted a hierarchical regression analysis to investigate the different effects of the 3 types of leisure activities on the mental health of older adults with MCI (N=901). Results: We found that leisure-time physical activity was the strongest predictor of enhanced life satisfaction, positive affect, and happiness, and reduced anxiety and loneliness. In addition, sedentary leisure was associated with reduced anxiety and loneliness and increased happiness. Conclusions: These findings suggest that engagement in leisure-time physical activity and sedentary leisure can be instrumental in promoting the life satisfaction and mental health of older adults with mild cognitive impairment.

Transcranial Color-Coded Doppler Cerebral Hemodynamics Following Aerobic Exercise Training: Outcomes From a Pilot Randomized Clinical Trial

Introduction

An active lifestyle with regular exercise is thought to decrease or delay the onset of Alzheimer dementia through increasing blood flow to the brain. We examined the mean flow velocity (MFV) and pulsatility index (PI) in the middle cerebral arteries of individuals randomized into two groups-a Usual Physical Activity (UPA) group and an Enhanced Physical Activity (EPA) exercise intervention group-to determine if exercise training is related to changes in cerebral blood flow.

Methods

We examined 23 participants, randomized into a UPA group (n=12) and an EPA group (n=11), with transcranial color-coded Doppler (TCCD) and cardiorespiratory fitness (VO2peak, mL/kg/min) testing at baseline and following a 26-week intervention. TCCD was used to measure MFV and PI. Participants in the EPA group completed supervised aerobic exercise training for 26 weeks. Kendall's tau b correlation was used to examine relationships between variables. The Wilcoxon Rank Sum tests were used to examine changes between the UPA and EPA groups.

Results

There was no significant change in MFV or PI in the UPA group or the EPA group (p-values >0.05) between baseline and 26 weeks; the change between the UPA and EPA groups was also not significant (p=0.603). There was no evidence of an association between change in VO2peak and change in MFV or PI (all p-values >0.05). Participants in the EPA group significantly increased their VO2peak compared to the UPA group (p=0.027).

Conclusion

This study did not demonstrate evidence of a significant change in the MFV in the middle cerebral arteries or evidence of a significant change in the PI between UPA and EPA groups. Future studies should be performed in larger cohorts and should consider use of personalized exercise programs to maximize understanding of how cerebrovascular hemodynamics change in structure and function with exercise for adults at risk for Alzheimer dementia.

Effects of Aerobic Exercise Training on Systemic Biomarkers and Cognition in Late Middle-Aged Adults at Risk for Alzheimer's Disease

Increasing evidence indicates that physical activity and exercise training may delay or prevent the onset of Alzheimer's disease (AD). However, systemic biomarkers that can measure exercise effects on brain function and that link to relevant metabolic responses are lacking. To begin to address this issue, we utilized blood samples of 23 asymptomatic late middle-aged adults, with familial and genetic risk for AD (mean age 65 years old, 50% female) who underwent 26 weeks of supervised treadmill training. Systemic biomarkers implicated in learning and memory, including the myokine Cathepsin B (CTSB), brain-derived neurotrophic factor (BDNF), and klotho, as well as metabolomics were evaluated. Here we show that aerobic exercise training increases plasma CTSB and that changes in CTSB, but not BDNF or klotho, correlate with cognitive performance. BDNF levels decreased with exercise training. Klotho levels were unchanged by training, but closely associated with change in VO2peak. Metabolomic analysis revealed increased levels of polyunsaturated free fatty acids (PUFAs), reductions in ceramides, sphingo- and phospholipids, as well as changes in gut microbiome metabolites and redox homeostasis, with exercise. Multiple metabolites (~30%) correlated with changes in BDNF, but not CSTB or klotho. The positive association between CTSB and cognition, and the modulation of lipid metabolites implicated in dementia, support the beneficial effects of exercise training on brain function. Overall, our analyses indicate metabolic regulation of exercise-induced plasma BDNF changes and provide evidence that CTSB is a marker of cognitive changes in late middle-aged adults at risk for dementia.

The Cognitive & Leisure Activity Scale (CLAS): A new measure to quantify cognitive activities in older adults with and without cognitive impairment

INTRODUCTION

Potentially modifiable dementia risk factors include diet and physical and cognitive activity. However, there is a paucity of scales to quantify cognitive activities. To address this, we developed the Cognitive & Leisure Activity Scale (CLAS).

METHODS

The CLAS was validated in 318 consecutive individuals with and without cognitive impairment. Psychometric properties were compared with sample characteristics, disease stage, and etiology.

RESULTS

The CLAS has very good data quality (Cronbach alpha: 0.731; 95% confidence interval: 0.67-0.78). CLAS scores correlated with gold standard measures of cognition, function, physical functionality, behavior, and caregiver burden. CLAS scores were positively correlated with other resilience factors (eg, diet, physical activity) and negatively correlated with vulnerability factors (eg, older age, frailty).

DISCUSSION

The CLAS is a brief inventory to estimate dosage of participation in cognitive activities. The CLAS could be used in clinical care to enhance cognitive activity or in research to estimate dosage of activities prior to an intervention.

The Effect of Baseline Patient and Caregiver Mindfulness on Dementia Outcomes

BACKGROUND

Mindfulness is the practice of awareness and living in the present moment without judgment. Mindfulness-based interventions may improve dementia-related outcomes. Before initiating interventions, it would be beneficial to measure baseline mindfulness to understand targets for therapy and its influence on dementia outcomes.

OBJECTIVE

This cross-sectional study examined patient and caregiver mindfulness with patient and caregiver rating scales and patient cognitive performance and determined whether dyadic pairing of mindfulness influences patient outcomes.

METHODS

Individuals (N = 291) underwent comprehensive evaluations, with baseline mindfulness assessed using the 15-item Applied Mindfulness Process Scale (AMPS). Correlation, regression, and mediation models tested relationships between patient and caregiver mindfulness and outcomes.

RESULTS

Patients had a mean AMPS score of 38.0±11.9 and caregivers had a mean AMPS score of 38.9±11.5. Patient mindfulness correlated with activities of daily living, behavior and mood, health-related quality of life, subjective cognitive complaints, and performance on episodic memory and attention tasks. Caregiver mindfulness correlated with preparedness, care confidence, depression, and better patient cognitive performance. Patients in dyads with higher mindfulness had better cognitive performance, less subjective complaints, and higher health-related quality of life (all p-values<0.001). Mindfulness effects on cognition were mediated by physical activity, social engagement, frailty, and vascular risk factors.

CONCLUSION

Higher baseline mindfulness was associated with better patient and caregiver outcomes, particularly when both patients and caregivers had high baseline mindfulness. Understanding the baseline influence of mindfulness on the completion of rating scales and neuropsychological test performance can help develop targeted interventions to improve well-being in patients and their caregivers.

The Resilience Index: A Quantifiable Measure of Brain Health and Risk of Cognitive Impairment and Dementia

BACKGROUND

There is increasing interest in lifestyle modification and integrative medicine approaches to treat and/or prevent mild cognitive impairment (MCI) and Alzheimer's disease and related dementias (ADRD).

OBJECTIVE

To address the need for a quantifiable measure of brain health, we created the Resilience Index (RI).

METHODS

This cross-sectional study analyzed 241 participants undergoing a comprehensive evaluation including the Clinical Dementia Rating and neuropsychological testing. Six lifestyle factors including physical activity, cognitive activity, social engagements, dietary patterns, mindfulness, and cognitive reserve were combined to derive the RI (possible range of scores: 1-378). Psychometric properties were determined.

RESULTS

The participants (39 controls, 75 MCI, 127 ADRD) had a mean age of 74.6±9.5 years and a mean education of 15.8±2.6 years. The mean RI score was 138.2±35.6. The RI provided estimates of resilience across participant characteristics, cognitive staging, and ADRD etiologies. The RI showed moderate-to-strong correlations with clinical and cognitive measures and very good discrimination (AUC: 0.836; 95% CI: 0.774-0.897) between individuals with and without cognitive impairment (diagnostic odds ratio = 8.9). Individuals with high RI scores (> 143) had better cognitive, functional, and behavioral ratings than individuals with low RI scores. Within group analyses supported that controls, MCI, and mild ADRD cases with high RI had better cognitive, functional, and global outcomes than those with low RI.

CONCLUSION

The RI is a brief, easy to administer, score and interpret assessment of brain health that incorporates six modifiable protective factors. Results from the RI could provide clinicians and researchers with a guide to develop personalized prevention plans to support brain health.