The Effects of Exercise on Cognitive Function in Older Adults With Different Types of Dementia: A Meta-Analysis

Abstract Combating dementia is a public health priority, and exercise training is one promising strategy for dementia prevention. However, its efficacy in promoting cognitive outcomes in different types of dementia remains unknown. We conducted a systematic review (N = 27) and meta-analysis (N = 24) of randomized controlled trials with cognitive function as a primary or secondary outcome. We aimed to assess the effect of exercise interventions on the cognitive function of older adults (>60 years) diagnosed with different types of dementia. We synthesized data from 2,441 older adults with dementia. Eleven trials included older adults with multiple types of dementia, eight with Alzheimer's disease, six with unspecified types of dementia, and two with vascular cognitive impairment. We performed random-effects models using robust variance estimation (RVE) and tested potential moderators using the approximate Hotelling-Zhang test (HTZ). Results suggest a small effect of exercise on cognitive function for all-cause dementia (g = 0.18; 95% CI: 0.04, 0.33; p = 0.016); however, the effects did not differ by type of dementia. Moderation analyses showed that trials that did not specify participants' severity of dementia, applied individual-level randomization, and had higher intervention adherence demonstrated larger exercise effects on cognitive function for all-cause dementia. We conclude that exercise promotes small improvements in the cognitive function of older adults with all-cause dementia. More research including different types of dementia is needed if we hope to determine the precise effects of exercise for each type of dementia.

Older cancer survivors present with unique challenges that may impact quality of life and increase physical dysfunction if not properly managed.Regular physical activity (PA) can help mitigate these effects.Silver Sneakers (SS), a free exercise program available to Medicare beneficiaries, has more than 16,000 US locations.To understand capacity of SS to serve older adults in our mixed rural/urban catchment area of Central Pennsylvania, we 1) identified all registered SS program locations in our 28-county catchment area and; 2) conducted phone questionnaires with SS program staff.Approximately 18 gyms closed during the pandemic, leaving a sample of 121 participating gyms.We talked to 80 gyms (66% response rate) to understand member and programming characteristics, training of staff and program marketing.Geographic locations of SS were mixed -39% in rural and 61% in urban counties; the majority (43%) were located in private gyms or YMCAs.The majority of gyms reported membership was equally mixed by gender and described ages of members as 65-80 years (94%).Program staff said that many members exercised several times per week with friends/family.Program staff also reported that social opportunities (35%) were a primary reason participants remained active in SS.Most (89%) of the facilities were still able to offer SS during the pandemic, with the majority (60%) adapting format to Zoom and other video platforms to conduct classes.Overall, SS programs offer a sustainable option to facilitate access to exercise programs and reduce barriers to PA among older adults in our catchment area.

THE ASSOCIATION BETWEEN LEISURE AND PHYSICAL ACTIVITY LEVEL WITH DEPRESSIVE SYMPTOMS AFTER 5-YEARS OF FOLLOW-UP
Milan Chang, 1 Hrafnhildur Eymundsdottir, 2 Alfons Ramel, 3 Sigurveig Sigurdardottir, 3 Vilmundur Gudnasson, 3 Lenore Launer, 4 and Palmi Jonsson, 5 , 1.The Icelandic Gerontological Research  Institute, Reykjavik, Hofuoborgarsvaoio, Iceland,  2. Landspitali University Hospitali, Landspitali University  Hospitali, Hofuoborgarsvaoio, Iceland, 3. University of  Iceland, Reykjavik, Hofuoborgarsvaoio, Iceland,  4. National Institute on Aging, Bethesda, Maryland, United  States, 5. University hospital Landspitali, Reykjavik,  Hofuoborgarsvaoio, Iceland  Background: Depressive symptoms in older adults are associated with socioeconomic status (SES), medical care, and physical activity.However, there is little evidence on the longitudinal association between level of leisure activity (LA) and physical activity (PA) with depressive symptoms among community-dwelling older adults in Iceland.The study examined an association of LA and PA at baseline with high depressive symptoms (HGDS) assessed after 5 years of follow-up among community-dwelling older adults.
Methods: A large community-based population residing in Reykjavik, Iceland participated in a longitudinal study with 5 years of follow-up (n=2957, 58% women, 74.9±4.8 yrs).Those with HGDS or dementia at baseline were excluded from the analysis.The reported activity was categorized into 2 groups as no-activity versus any-activity.Depressive symptoms were assessed by the 15-item Geriatric Depression Scale (GDS) on average 5 years later.

Conclusion:
Our study shows that any LA among older adults is associated with having less depressive symptoms 5 years later among community-dwelling older adults while having any PA was not associated with depressive symptoms after 5 years of follow-up.Physical activity is an effective intervention to prevent or delay cognitive decline and dementia in older adults; however, many have difficulty achieving recommended moderate-to vigorous-intensity guidelines.This study examined the impact of low-intensity daily walking activity on executive cognitive and brain function in 66 older adults (mean age=67.26; SD=6.04).Daily walking activity was measured using a step activity monitor and brain function was assessed using functional magnetic resonance imaging during the Flanker task.Analyses included whole and region of interest (ROI) in the right middle frontal gyrus (RMFG), occipital cortex (OCC) and anterior cingulate (ACC).Partial correlations were performed between step activity, behavioral performance, and ROI activation, adjusting for age and education.Most of the step activity was in the low-intensity range.No associations were observed between step activity and task performance (p>.05).Task-related activation occurred in the RMFG, lateral OCC and paracingulate (p<.01).Increased activation in the RMFG was associated with greater amount r(62)=.390,p=.001, duration r(62)=.309,p=.013 and frequency r(62)=.327,p=.007 of step activity.Stratification by sex revealed a positive association between amount of step activity and RMFG activation in women r(44)= .360,p=.014, but not men.Whole brain correlation revealed that amount of step activity was positively associated with precuneus activation (p<.01), an area impacted early in Alzheimer's disease.These results support the benefits of low intensity daily walking activity on prefrontal function in older adults and suggest the importance of designing attainable and sustainable physical activity interventions to promote brain health in older adults.

THE EFFECTS OF EXERCISE ON COGNITIVE FUNCTION IN OLDER ADULTS WITH DIFFERENT TYPES OF DEMENTIA: A META-ANALYSIS
Guilherme Balbim, 1 Teresa Liu-Ambrose, 1 Ryan Falck, 1 Cindy Barha, 1 Jennifer Davis, 2 Samantha Starkey, 1 and Alexis Bullock, 3 , 1. University of British Columbia,Vancouver,British Columbia,Canada,Kelowna,British Columbia,Canada,3. the University of British Columbia,Vancouver,British Columbia,Canada Combating dementia is a public health priority, and exercise training is one promising strategy for dementia prevention.However, its efficacy in promoting cognitive outcomes in different types of dementia remains unknown.We conducted a systematic review (N = 27) and meta-analysis (N = 24) of randomized controlled trials with cognitive function as a primary or secondary outcome.We aimed to assess the effect of exercise interventions on the cognitive function of older adults (>60 years) diagnosed with different types of dementia.We synthesized data from 2,441 older adults with dementia.Eleven trials included older adults with multiple types of dementia, eight with Alzheimer's disease, six with unspecified types of dementia, and two with vascular cognitive impairment.We performed random-effects models using robust variance estimation (RVE) and tested potential moderators using the approximate Hotelling-Zhang test (HTZ).Results suggest a small effect of exercise on cognitive function for all-cause dementia (g = 0.18; 95% CI: 0.04, 0.33; p = 0.016); however, the effects did not differ by type of dementia.Moderation analyses showed that trials that did not specify participants' severity of dementia, applied individuallevel randomization, and had higher intervention adherence demonstrated larger exercise effects on cognitive function for all-cause dementia.We conclude that exercise promotes small improvements in the cognitive function of older adults with all-cause dementia.More research including different types of dementia is needed if we hope to determine the precise effects of exercise for each type of dementia.

THE INVENTORY OF PHYSICAL ACTIVITY BARRIERS FOR ADULTS 50 YEARS AND OLDER: REFINEMENT AND VALIDATION
Mariana Wingood, 1 Salene Jones, 2 Nancy Gell, 3 Denise Peters, 3 and Jennifer Brach, 4 , 1. University of Vermont, University of Vermont, Vermont, United States,2. Fred Hutchinson Cancer Research Center,Seattle,Washington,United States,3. University of Vermont,Burlington,Vermont,United States,4. University of pittsburgh,Pittsburgh,Pennsylvania,United States Addressing physical activity (PA) barriers is an essential component of increasing PA among the 56-73% of community-dwelling adults 50 years and older who are not performing the recommended 150 minutes of moderateto-vigorous PA.As there is no feasible, multi-factorial tool to assess PA barriers among this population, we developed and validated a PA barrier assessment tool called the Inventory of Physical Activity Barriers (IPAB).We collected cross-sectional data on 503 adults (mean age 70.1), with 79 participants completing the scale twice for test-retest reliability and 64 completing a cross-over design examining the ability to use two administration formats interchangeably.Our analyses consisted of exploratory and confirmatory factor analysis, Cronbach alpha, intraclass correlation coefficient, Bland-Altman Plot, and t-tests.Using factor analysis, we identified and confirmed an eight-factor solution consisting of 27 items.The 27-item IPAB is internally consistent (alpha= 0.91), has a high test-retest reliability (intraclass correlation coefficient=0.99), and can differentiate between individuals who meet the recommended levels of PA and those who do not (p < 0.001).The IPAB scores ranged between 1.00-3.11for the paper format (mean=1.78)and 1.07-3.48for the electronic format (mean=1.78),with no statistical difference between the paper and electronic administration formats (p=0.94),resulting in the conclusion that the two administration formats can be used interchangeably.Participant feedback illustrates that the IPAB is easy to use, has clear instruction, and is an appropriate length.The newly validated IPAB scale can be used to develop individualized PA interventions that address PA barriers among patients 50 years and older.Balance confidence reflects one's estimate of their ability to maintain balance and avoid falls.Extensive literature has shown the relationships between balance confidence, functional limitations, and falls in later life.However, change in balance confidence, especially within short timescale, remains largely unknown and deserves further research.In this study, we aimed to investigate how older adults' balance confidence would change over 30 days and explore whether baseline characteristics would explain the individual differences in change.We used data from the Daily Balance Project that employed intensive-repeated measurements to examine the dynamics of subjective and objective fall risk across a month.Twenty-one participants (age=78.6±5.8,48%female) were enrolled, and individual characteristics were measured upon recruitment.Throughout the study, participants self-reported their daily balance confidence using the Activity-Specific Balance Confidence (ABC) Scale.We performed growth modeling techniques to examine change within a multilevel framework.Our results showed that overall, ABC scores were high (79.9±17.4) at first, but the linear change was nonsignificant (b=0.03,SE=0.21, p=.89) on average.However, we found that balance confidence increased in individuals with higher educational attainment (b=0.37,SE=0.13, p<.01) and decreased among those with greater physical fall risk (b=-0.18,SE=0.07, p<.01) and accurate understanding of fall risk at baseline (b=-0.24,SE= 0.12, p=.04).Although ABC scores were stable within the period of one month, our study highlights the distinction of individual characteristics in the process of balance confidence appraisal.We suggest that these nuances should be taken into account when developing more fine-grained fall risk assessments and interventions.

Session 9255 (Poster) FALLS: SCREENING, RISKS, AND PREVALENCE CAPTURING CHANGE IN BALANCE CONFIDENCE OVER 30 DAYS: INSIGHTS GAINED FROM A MICRO- LONGITUDINAL STUDY Tai
-Te Su, 1 Aileen Griffin, 2 Faith-Christina Washington, 1 Jacob Sosnoff, 3 and Shannon Meija, 4 , 1. University of Illinois at Urbana-Champaign, Champaign, Illinois, United States, 2. University of Illinois at Urbana-Champaign, Aurora, Illinois, United States, 3. School of Health Professions, University of Kansas Medical Center, Kansas City, Kansas, United States, 4. University of Illinois, Champaign, Illinois, United States