A pilot study evaluating the association between physical activity and cognition among individuals with Parkinson's disease

Relationships between physical activities performed under free-living conditions and non-motor symptoms in people with Parkinson's: A systematic review and meta-analysis

BACKGROUND

Physical activities performed under free-living conditions that are unsupervised in the home or community have the potential to modulate non-motor symptoms in people with Parkinson's disease.

OBJECTIVE

This systematic review investigates the relationships between physical activities performed in free-living conditions and non-motor symptoms in people with Parkinson's disease: cognition, anxiety, apathy, depression, sleep disturbances, fatigue, and pain.

DATA SOURCES

A database search was performed on Scopus, Web of Science, Ovid (PsycINFO), CINAHL, PubMed, and ProQuest (Health and Medicine).

REVIEW METHODS

Observational studies published from 2000 to 2024 that examined the relationships between physical activity and non-motor symptoms were included. The methodological quality of reports was evaluated using critical appraisal checklists appropriate to the study design. Where appropriate, a meta-analysis was conducted to combine data from the included articles.

RESULTS

A total of 14 articles met the criteria and used various tools to evaluate non-motor symptoms and physical activity. Meta-analyses showed that people with Parkinson's who are more physically active have better global cognition [β ranged from 0.12 to 0.28; p = 0.00-0.02] and less affective disorders [β -0.20, p = 0.00]. Increased physical activity levels were also associated with better sleep quality (n = 1) and less chronic pain (n = 1). The overall methodological quality of the included articles was considered high.

CONCLUSION

Engagement in increased levels of physical activities performed under free-living conditions is associated with better cognition and less anxiety, apathy, and depression in people with Parkinson's disease.

Exercise Habits in People with Parkinson's: A Multinational Survey

BACKGROUND

Exercise has been demonstrated to result in improvements in physical function, cognition, and quality of life in People with Parkinson's (PwP) but its adoption is variable.

OBJECTIVES

To investigate exercise preferences, levels, influencing factors among a diverse Parkinson's disease (PD) population, to understand exercise adoption patterns and plan informed interventions.

METHODS

A cross-sectional survey collected data through online platforms and paper-based methods. The Exercise Index (ExI) calculated exercise level based on frequency and duration.

RESULTS

Of 2976 PwP, 40.6% exercised regularly, 38.3% occasionally, and 21.2% did not exercise. The overall mean ExI was 18.99 ± 12.37. Factors associated with high exercise levels included exercising in groups (ExI 24-26), weightlifting (ExI 27 (highest)), using muscle-building equipment (ExI 25-26), and exercising at home following an app (ExI 26). A positive trend between ExI and varied exercise groups, locations, types, and equipment was observed. No expected benefit from exercise achieved the lowest ExI (8). Having at least two exercise-promoting factors, a bachelor's degree or higher, receiving exercise advice at initial visits, and aged ≤40 years at PD onset were strong predictors of exercise (adjust OR = 7.814; 6.981; 4.170; 3.565). Falls and "other" most troublesome PD symptoms were negative predictors (aOR = 0.359; 0.466). Barriers to exercise did not predict the odds of exercise.

CONCLUSIONS

The study shows that PwP's exercise behavior is influenced by their exercise belief, age at PD onset, doctor's advice at initial visits, education level, symptoms, and exercise-promoting factors. High exercise levels were associated with certain types of exercises and exercising in groups.

Cognition and Activity of Daily Living Function in people with Parkinson's disease

The ability to perform activities of daily living (ADL) function is a multifaceted construct that reflects functionality in different daily life situations. The loss of ADL function due to cognitive impairment is the core feature for the diagnosis of Parkinson's disease dementia (PDD). In contrast to Alzheimer's disease, ADL impairment in PD can be compromised by various factors, including motor and non-motor aspects. This narrative review summarizes the current state of knowledge on the association of cognition and ADL function in people with PD and introduces the concept of "cognitive ADL" impairment for those problems in everyday life that are associated with cognitive deterioration as their primary cause. Assessment of cognitive ADL impairment is challenging because self-ratings, informant-ratings, and performance-based assessments seldomly differentiate between "cognitive" and "motor" aspects of ADL. ADL function in PD is related to multiple cognitive domains, with attention, executive function, and memory being particularly relevant. Cognitive ADL impairment is characterized by behavioral anomalies such as trial-and-error behavior or task step omissions, and is associated with lower engagement in everyday behaviors, as suggested by physical activity levels and prolonged sedentary behavior. First evidence shows that physical and multi-domain interventions may improve ADL function, in general, but the evidence is confounded by motor aspects. Large multicenter randomized controlled trials with cognitive ADL function as primary outcome are needed to investigate which pharmacological and non-pharmacological interventions can effectively prevent or delay deterioration of cognitive ADL function, and ultimately the progression and conversion to PDD.

A systematic review of the associations between sedentary behavior, physical inactivity, and non-motor symptoms of Parkinson's disease

BACKGROUND

Parkinson's disease (PD), known for motor symptoms, often presents early non-motor issues that significantly affect patients' quality of life. While effective treatments are limited, physical activity and exercise offer potential benefits. However, an overlooked aspect of the movement intensity continuum is prolonged sitting or sedentary behavior, and physical inactivity. Thus, this study aimed to conduct a systematic review investigating the associations between sedentary behavior, physical inactivity, and non-motor symptoms, specifically cognitive impairment, depression, and poor sleep in PD.

METHODS

Conforming to PRISMA guidelines, a systematic search of the literature was conducted via electronic databases including MEDLINE, CINAHL, Scopus, PubMed and PsycINFO up to February 28, 2023. Studies were included if they investigated associations between sedentary behavior or physical inactivity and at least one non-motor symptom such as depression, poor sleep, and/or cognitive impairment, in adults aged 18 years or older with PD. Quality assessment of the studies was performed using the Newcastle-Ottawa scale for cross-sectional and cohort studies.

RESULTS

Of the 463 publications found, 7 studies met the inclusion criteria (n = 980 unique participants). Sample sizes ranged from 17 to 487 participants, and all studies were observational, conducted in home or community settings. Collectively, these studies show that higher amounts of both objectively-measured and self-reported sedentary time are associated with worse scores on standardized measures of cognition and the Parkinson's Disease Questionnaire (PDQ) summary index and its subscales, such as cognition (memory and concentration). Additionally, longitudinal cohort studies suggest that physical inactivity and higher sedentary behavior are associated with depression and cognitive impairment in PD. Less sleep was associated with higher sedentary behavior.

CONCLUSION

Associations observed between physical inactivity, sedentary behavior, and non-motor symptoms in PD underscore the need to address these factors for enhanced well-being. Further well-designed studies are essential to assess the impact of reducing sedentary behavior and physical inactivity on non-motor symptoms in PD. Prospero registration number: PROSPERO (ID: CRD42023405422) on April 11, 2023.

Comparing the effects of augmented virtual reality treadmill training versus conventional treadmill training in patients with stage II-III Parkinson's disease: the VIRTREAD-PD randomized controlled trial protocol

Background

Intensive treadmill training (TT) has been documented to improve gait parameters and functional independence in Parkinson's Disease (PD), but the optimal intervention protocol and the criteria for tailoring the intervention to patients' performances are lacking. TT may be integrated with augmented virtual reality (AVR), however, evidence of the effectiveness of this combined treatment is still limited. Moreover, prognostic biomarkers of rehabilitation, potentially useful to customize the treatment, are currently missing. The primary aim of this study is to compare the effects on gait performances of TT + AVR versus TT alone in II-III stage PD patients with gait disturbance. Secondary aims are to assess the effects on balance, gait parameters and other motor and non-motor symptoms, and patient's satisfaction and adherence to the treatment. As an exploratory aim, the study attempts to identify biomarkers of neuroplasticity detecting changes in Neurofilament Light Chain concentration T0-T1 and to identify prognostic biomarkers associated to blood-derived Extracellular Vesicles.

Methods

Single-center, randomized controlled single-blind trial comparing TT + AVR vs. TT in II-III stage PD patients with gait disturbances. Assessment will be performed at baseline (T0), end of training (T1), 3 (T2) and 6 months (T3, phone interview) from T1. The primary outcome is difference in gait performance assessed with the Tinetti Performance-Oriented Mobility Assessment gait scale at T1. Secondary outcomes are differences in gait performance at T2, in balance and spatial-temporal gait parameters at T1 and T2, patients' satisfaction and adherence. Changes in falls, functional mobility, functional autonomy, cognition, mood, and quality of life will be also assessed at different timepoints. The G*Power software was used to estimate a sample size of 20 subjects per group (power 0.95, α < 0.05), raised to 24 per group to compensate for potential drop-outs. Both interventions will be customized and progressive, based on the participant's performance, according to a predefined protocol.

Conclusion

This study will provide data on the possible superiority of AVR-associated TT over conventional TT in improving gait and other motor and non-motor symptoms in persons with PD and gait disturbances. Results of the exploratory analysis could add information in the field of biomarker research in PD rehabilitation.

Physical activity and lifestyle modifications in the treatment of neurodegenerative diseases

Neurodegenerative diseases have reached alarming numbers in the past decade. Unfortunately, clinical trials testing potential therapeutics have proven futile. In the absence of disease-modifying therapies, physical activity has emerged as the single most accessible lifestyle modification with the potential to fight off cognitive decline and neurodegeneration. In this review, we discuss findings from epidemiological, clinical, and molecular studies investigating the potential of lifestyle modifications in promoting brain health. We propose an evidence-based multidomain approach that includes physical activity, diet, cognitive training, and sleep hygiene to treat and prevent neurodegenerative diseases.

Physical activity intensity is associated with cognition and functional connectivity in Parkinson's disease

BACKGROUND

Cognitive impairment is common in Parkinson's disease (PD) and often leads to dementia, with no effective treatment. Aging studies suggest that physical activity (PA) intensity has a positive impact on cognition and enhanced functional connectivity may underlie these benefits. However, less is known in PD. This cross-sectional study examined the relationship between PA intensity, cognitive performance, and resting state functional connectivity in PD and whether PA intensity influences the relationship between functional connectivity and cognitive performance.

METHODS

96 individuals with mild-moderate PD completed a comprehensive neuropsychological battery. Intensity of PA was objectively captured over a seven-day period using a wearable device (ActiGraph). Time spent in light and moderate intensity PA was determined based on standardized actigraphy cut points. Resting-state fMRI was assessed in a subset of 50 individuals to examine brain-wide functional connectivity.

RESULTS

Moderate intensity PA (MIPA), but not light PA, was associated with better global cognition, visuospatial function, memory, and executive function. Individuals who met the WHO recommendation of ≥150 min/week of MIPA demonstrated better global cognition, executive function, and visuospatial function. Resting-state functional connectivity associated with MIPA included a combination of brainstem, hippocampus, and regions in the frontal, cingulate, and parietal cortices, which showed higher connectivity across the brain in those achieving the WHO MIPA recommendation. Meeting this recommendation positively moderated the associations between identified functional connectivity and global cognition, visuospatial function, and language.

CONCLUSION

Encouraging MIPA, particularly the WHO recommendation of ≥150 min of MIPA/week, may represent an important prescription for PD cognition.

Factors Influencing Habitual Physical Activity in Parkinson’s Disease: Considering the Psychosocial State and Wellbeing of People with Parkinson’s and Their Carers

Participating in habitual physical activity (HPA) may slow onset of dependency and disability for people with Parkinson’s disease (PwP). While cognitive and physical determinants of HPA are well understood, psychosocial influences are not. This pilot study aimed to identify psychosocial factors associated with HPA to guide future intervention development. Sixty-four PwP participated in this study; forty had carer informants. PwP participants wore a tri-axial accelerometer on the lower back continuously for seven days at two timepoints (18 months apart), measuring volume, pattern and variability of HPA. Linear mixed effects analysis identified relationships between demographic, clinical and psychosocial data and HPA from baseline to 18 months. Key results in PwP with carers indicated that carer anxiety and depression were associated with increased HPA volume (p < 0.01), while poorer carer self-care was associated with reduced volume of HPA over 18 months (p < 0.01). Greater carer strain was associated with taking longer walking bouts after 18 months (p < 0.01). Greater carer depression was associated with lower variability of HPA cross-sectionally (p = 0.009). This pilot study provides preliminary novel evidence that psychosocial outcomes from PwP’s carers may impact HPA in Parkinson’s disease. Interventions to improve HPA could target both PwP and carers and consider approaches that also support psychosocial wellbeing.

Wearable GPS and Accelerometer Technologies for Monitoring Mobility and Physical Activity in Neurodegenerative Disorders: A Systematic Review

Neurodegenerative disorders (NDDs) constitute an increasing global burden and can significantly impair an individual's mobility, physical activity (PA), and independence. Remote monitoring has been difficult without relying on diaries/questionnaires which are more challenging for people with dementia to complete. Wearable global positioning system (GPS) sensors and accelerometers present a cost-effective and noninvasive way to passively monitor mobility and PA. In addition, changes in sensor-derived outcomes (such as walking behaviour, sedentary, and active activity) may serve as potential biomarkers of disease onset, progression, and response to treatment. We performed a systematic search across four databases to identify papers published within the past 5 years, in which wearable GPS or accelerometers were used to monitor mobility or PA in patients with common NDDs (Parkinson's disease, Alzheimer's disease, motor neuron diseases/amyotrophic lateral sclerosis, vascular parkinsonism, and vascular dementia). Disease and technology-specific vocabulary were searched singly, and then in combination, identifying 4985 papers. Following deduplication, we screened 3115 papers and retained 28 studies following a full text review. One study used wearable GPS and accelerometers, while 27 studies used solely accelerometers in NDDs. GPS-derived measures had been validated against current gold standard measures in one Parkinson's cohort, suggesting that the technology may be applicable to other NDDs. In contrast, accelerometers are widely utilised in NDDs and have been operationalised in well-designed clinical trials.

Objectively assessed physical activity and sedentary behavior and global cognitive function in older adults: a systematic review

BACKGROUND

Both physical activity (PA) and sedentary behavior (SB) are important factors for healthy ageing. This systematic review aimed to determine the association of objectively assessed (instrumented) PA and SB with global cognitive function in older adults.

METHODS

PubMed, Embase, the Cochrane Library (via Wiley), CINAHL, PsychINFO, and SPORTDiscus (via EBSCO) were searched from inception to June 21, 2020 for articles that described associations of objectively assessed PA/SB with global cognitive function in older adults aged 60 years and older. Results were synthesized using an effect direction heat map and albatross plots portrayed estimated effect sizes (standardized regression coefficients (βs)), which were summarized in boxplots.

RESULTS

In total, 45 articles were included representing a total of 15,817 older adults (mean/median age ranged from 65 to 88 years; 49.5% female). Longitudinal studies (n = 7) showed that higher moderate-to-vigorous and light PA (MVPA and LPA, respectively) and lower SB were associated with better global cognitive function. Standardized βs of cross-sectional studies (n = 38) showed that lower SB (median [IQR], β = 0.078 [0.004-0.184] and higher LPA (β = 0.096 [0.046-0.188]), activity counts (β = 0.131 [0.049-0.224]), number of steps (β = 0.155 [0.096-0.246]), MVPA (β = 0.163 [0.069-0.285]) and total PA (TPA) (β = 0.174 [0.147-0.255]) were associated with better global cognitive function.

CONCLUSIONS

Higher PA and lower SB are associated with better global cognitive function in older adults. The greatest estimated effect sizes were found for moderate-to-vigorous and TPA, suggesting that greater duration of any PA, and high intensity PA could be most beneficial for global cognitive function.

Music-based physical therapy in Parkinson's disease: An approach based on international Classification of Functioning, Disability and Health

INTRODUCTION

Several studies suggests that the provision of auditory cues with music could be beneficial for people with Parkinson's Disease (PD). The aim of the study was to evaluate the effects of music-based physical therapy on the international Classification of Functioning, Disability and Health (ICF) components: disability, cognition, muscle strength, balance, and functional mobility.

METHODS

This was a controlled, non-randomized clinical trial involving 13 individuals with PD assessed at three times: baseline, period 1 (treatment), and period 2 (no treatment). The variables analyzed were: disability by Unified Parkinson's Disease Rating Scale (UPDRS) and Hoehn & Yahr (H&Y), cognitive function by Trail Making Test, muscle strength by Medical Research Council (MRC) and sitting-rising (SR) test, balance and functional mobility by Berg Balance Scale (BBS) and Timed up and Go (TUG). ANOVA with post-hoc multiple comparison was used to determine statistical differences between the baseline, period 1 and 2.

RESULTS

there was statistically significant difference among the period 1 and 2 for the cognitive function; there was a statistically significant difference between the period 1 and 2 in SR test; in the balance evaluation by BBS, an increase was observed between the baseline and the period 1, followed by a decrease in period 2; in the TUG, there was an increase between the period 1 and 2.

CONCLUSION

the music-based physical therapy, according to the ICF construct, was able to improve balance and functional mobility in individuals with PD. The functional gains were not maintained when the therapy was discontinued.

Cognitive impairment and sedentary behavior predict health-related attrition in a prospective longitudinal Parkinson's disease study

INTRODUCTION

In Parkinson's disease (PD), the high burden of motor and non-motor symptoms, such as cognitive impairment or falls, is associated with rapid disease progression and mortality. This is often reflected by an increased drop-out rate of PD patients in longitudinal studies. Active physical behavior can impact the disease course beneficially and has an overall positive effect on health. Contrarily, sedentary behavior is associated with cognitive impairment in PD. The aim of this study was to investigate whether sedentary physical behavior assessed in the home environment and cognitive impairment can predict health-related study attrition due to sickness and death in PD.

METHODS

Data of 45 PD patients, longitudinally assessed, were analyzed. Of those, 20 patients completed six yearly visits, 16 dropped out due to sickness or death, and nine for other reasons. All patients wore a mobile device to assess physical behavior and completed cognitive testing.

RESULTS

Logistic regression revealed global cognition was the primary predictor for health-related drop-out in varying models (p ≤ .04). In the survival analysis, cognitive impairment (p = .005) and longer sedentary mean bout length (p = .02) were associated with drop-out due to sickness and death. The occurrence of health-related study drop-out or death was highest in patients with both impaired cognition and longer sedentary bouts.

CONCLUSIONS

Cognition was the primary predictor for study drop-out due to sickness and death. However, it seems that sedentary behavior might have a potential negative influence on PD patients' health, especially those with cognitive impairment.

Sedentary Time is Associated with Worse Attention in Parkinson's Disease: A Pilot Study

Objective

Cognitive symptoms of Parkinson’s disease (PD) may be alleviated by moderate-to-vigorous physical activity (MVPA), but no published research has characterized the relationship between objectively measured sedentary behavior and cognitive symptoms of PD. Therefore, the objective of this study was to assess the cross-sectional relationship between sedentary time and cognitive performance in a small pilot sample of individuals with mild-to-moderate PD.

Methods

Objective measures of sedentary time were obtained using an armband accelerometer. Cognition was assessed with the Parkinson’s Disease Cognitive Rating Scale and a computerized task-switching paradigm.

Results

The percentage of awake time spent in sedentary activities was negatively correlated with attention (β = -14.20, t(12) = -2.47, p = 0.03) but not other cognitive domains (p > 0.05) after controlling for MVPA and medication dosage.

Conclusion

Sedentary activity may have unique associations with cognition, particularly attention, over and above MVPA in individuals with PD.

Effects of Exercise on Long-Term Potentiation in Neuropsychiatric Disorders

Various neuropsychiatric conditions, such as depression, Alzheimer's disease, and Parkinson's disease, demonstrate evidence of impaired long-term potentiation, a cellular correlate of episodic memory function. This chapter discusses the mechanistic effects of these neuropsychiatric conditions on long-term potentiation and how exercise may help to attenuate these detrimental effects.

An integrated model of acute exercise on memory function

Memory is a complex cognition that plays a critical role in daily functioning. This review discusses the dynamic effects of acute exercise on memory function, via a hypothesized exercise-memory interaction model, taking into consideration multiple memory systems and exercise parameters.

Physical activity mediates the association between striatal dopamine transporter availability and cognition in Parkinson's disease

OBJECTIVE

Associations between cognition and nigrostriatal dopaminergic deficits in Parkinson's disease have been documented in the literature, but are incompletely understood. Here we studied the extent to which physical activity mediates the relationship between striatal dopamine transporter availability and global cognition among patients with Parkinson's disease.

METHODS

Data from 174 patients from a multi-center study were analyzed using regression-based mediation analysis. Striatal dopamine transporter binding ratio (SBR), Physical Activity Scale for Elderly (PASE), and Montreal Cognitive Assessment (MoCA) were used to evaluate patients' dopamine transporter availability (DAT), physical activity, and global cognition respectively at the time of testing. Confidence intervals (CI) of 95% were established using a bootstrapping approach to test the statistical significance of the direct, indirect (i.e., mediation), and total effects of the mediation model.

RESULTS

As hypothesized, the positive mediating effect of physical activity in the association between DAT and global cognition was significant, while adjusting for age (95% CI [0.0030, 0.3942]). Specifically, higher SBRs were positively associated with PASE scores, which in turn, were positively associated with MoCA scores. Secondary analyses revealed a similar positive mediation effect of physical activity for DAT in the caudate and putamen separately (95% CI [0.0377, 0.4231] and [0.0211, 1.1000], respectively).

CONCLUSION

We report that the relationship of dopamine transporter availability with global cognition in Parkinson's disease is mediated by physical activity. Pending further research for specific recommendations, interventions to increase physical activity as tolerated should be considered in patients with Parkinson's disease.

Exercise and cardiorespiratory fitness on subjective memory complaints

The purpose of this study was to examine the association between exercise and estimated cardiorespiratory fitness on subjective memory complaints in young adults. Four-hundred and 64 young adult college students (18-35 yrs) completed an online survey. Exercise behavior was assessed from the Physical Activity Vital Signs Questionnaire. Cardiorespiratory fitness was evaluated from an algorithm that included an assessment of age, gender, body mass index, waist circumference, resting heart rate, habitual physical activity behavior, and smoking status. Subjective memory complaints were assessed using the Prospective-Retrospective Memory Questionnaire. Subjective memory complaints were common among this young adult sample. However, exercise was not statistically significantly associated with prospective (β = -0.002, P = 0.25) or retrospective (β = -0.001, P = 0.26) memory complaints. Results were similar for cardiorespiratory fitness. In conclusion, we did not observe an association between exercise and estimated cardiorespiratory fitness on subjective memory complaints in young adults.

Association between Objectively Measured Physical Activity and Gait Patterns in People with Parkinson's Disease: Results from a 3-Month Monitoring

Background

Although physical activity (PA) is known to be beneficial in improving motor symptoms of people with Parkinson's disease (pwPD), little is known about the relationship between gait patterns and features of PA performed during daily life.

Objective

To verify the existence of possible relationships between spatiotemporal and kinematic parameters of gait and amount/intensity of PA, both instrumentally assessed.

Methods

Eighteen individuals affected by PD (10F and 8M, age 68.0 ± 10.8 years, 1.5 ≤ Hoehn and Yahr (H&Y) < 3) were required to wear a triaxial accelerometer 24 h/day for 3 consecutive months. They also underwent a 3D computerized gait analysis at the beginning and end of the PA assessment period. The number of daily steps and PA intensity were calculated on the whole day, and the period from 6:00 to 24:00 was grouped into 3 time slots, using 3 different cut-point sets previously validated in the case of both pwPD and healthy older adults. 3D gait analysis provided spatiotemporal and kinematic parameters of gait, including summary indexes of quality (Gait Profile Score (GPS) and Gait Variable Score (GVS)).

Results

The analysis of hourly trends of PA revealed the existence of two peaks located in the morning (approximately at 10) and in the early evening (between 18 and 19). However, during the morning time slot (06:00–12:00), pwPD performed significantly higher amounts of steps (4313 vs. 3437 in the 12:00–18:00 time slot, p < 0.001, and vs. 2889 in the 18:00–24:00 time slot, p=0.021) and of moderate-to-vigorous PA (43.2% vs. 36.3% in the 12:00–18:00 time slot, p=0.002, and vs. 31.4% in the 18:00–24:00 time slot, p=0.049). The correlation analysis shows that several PA intensity parameters are significantly associated with swing-phase duration (rho = −0.675 for sedentary intensity, rho = 0.717 for moderate-to-vigorous intensity, p < 0.001), cadence (rho = 0.509 for sedentary intensity, rho = −0.575 for moderate-to-vigorous intensity, p < 0.05), and overall gait pattern quality as expressed by GPS (rho = −0.498 to −0.606 for moderate intensity, p < 0.05) and GVS of knee flexion-extension (rho = −0.536 for moderate intensity, p < 0.05).

Conclusions

Long-term monitoring of PA integrated by the quantitative assessment of spatiotemporal and kinematic parameters of gait may represent a useful tool in supporting a better-targeted prescription of PA and rehabilitative treatments in pwPD.

Moderate intensity physical activity associates with CSF biomarkers in a cohort at risk for Alzheimer's disease

INTRODUCTION

Alzheimer's disease (AD) is characterized by the presence of amyloid β (Aβ) plaques, neurofibrillary tangles, and neurodegeneration, evidence of which may be detected in vivo via cerebrospinal fluid (CSF) sampling. Physical activity (PA) has emerged as a possible modifier of these AD-related pathological changes. Consequently, the aim of this study was to cross-sectionally examine the relationship between objectively measured PA and CSF levels of Aβ42 and tau in asymptomatic late-middle-aged adults at risk for AD.

METHODS

Eighty-five cognitively healthy late-middle-aged adults (age = 64.31 years, 61.2% female) from the Wisconsin Registry for Alzheimer's Prevention participated in this study. They wore an accelerometer (ActiGraph GT3X+) for one week to record free-living PA, yielding measures of sedentariness and various intensities of PA (i.e., light, moderate, and vigorous). They also underwent lumbar puncture to collect CSF, from which Aβ42, total tau, and phosphorylated tau were immunoassayed. Regression analyses were used to examine the association between accelerometer measures and CSF biomarkers, adjusting for age, sex, and other relevant covariates.

RESULTS

Engagement in moderate PA was associated with higher Aβ42 (P = .008), lower total tau/Aβ42 (P = .006), and lower phosphorylated tau/Aβ42 (P = .030). In contrast, neither light nor vigorous PA was associated with any of the biomarkers. Increased sedentariness was associated with reduced Aβ42 (P = .014).

DISCUSSIONS

In this cohort, moderate PA, but not light or vigorous, was associated with a favorable AD biomarker profile, while sedentariness was associated with greater Aβ burden. These findings suggest that a physically active lifestyle may play a protective role against the development of AD.