Co-design of dementia prevention program for Aboriginal Australians (DAMPAA).

INTRODUCTION: Dementia is highly prevalent in older Aboriginal Australians, with several modifiable risk factors. Currently, there is limited evidence on how to prevent cognitive decline in Aboriginal Australians. METHODS: Based on our Theory of Change (ToC) framework, we co-developed the Dementia risk management and prevention program for Aboriginal Australians (DAMPAA) aged over 45 years in partnership with Aboriginal community-controlled organizations (ACCOs) and Elders. Qualitative data were collected through ACCO staff workshops, Elders yarning, and governance groups to inform the protocol. Additionally, we conducted a small pilot study. RESULTS: Expected DAMPAA ToC outcomes are: (1) improved daily function, (2) better cardiovascular risk management, (3) falls reduction, (4) improved quality of life, and (5) reduced cognitive decline. Attendance enablers are social interaction, environment, exercise type/level, and logistics. DISCUSSION: Findings suggest that ToC is an effective collaborative approach for co-designing Aboriginal health programs.

Effects of testosterone treatment, with and without exercise training, on ambulatory blood pressure in middle-aged and older men.

CONTEXT: With age, testosterone (T) and physical activity levels often decline in parallel. The effect of combining T treatment and exercise training on ambulatory blood pressure (ABP) is unclear. OBJECTIVE: To assess T and exercise effects, alone and in combination, on ABP in men aged 50-70 years, waist circumference ≥ 95 cm and low-normal serum T (6-14 nmol/L), without organic hypogonadism. DESIGN: A 2 × 2 factorial randomised, placebo-controlled study. INTERVENTION: Randomization to daily transdermal AndroForte5® (Testosterone 5.0%w/v, 100 mg in 2 ml) cream (T), or matching placebo (P) (double-blind), and to supervised exercise (Ex) or no additional exercise (NEx), for 12 weeks. RESULTS: Average 24-h systolic blood pressure (SBP) increased with T treatment (testosterone*time, p = .035). Average 24-h SBP increased in T+Ex (T+Ex:+3.0 vs. P+NEx: -3.0 mmHg, p = .026) driven by day-time changes (T+Ex:+3.5 vs. P+NEx: -3.0 mmHg, p = .026). There was an effect of T for 24-h average diastolic blood pressure (DBP, testosterone*time, p = .044) driven by the decrease in P+Ex (P+Ex: -3.9 vs. T+NEx: -0.5 mmHg, p = .015). Night-time DBP was lower with exercise (P+Ex: -4.0 vs. P+NEx: +0.7 mmHg, p = .032). The effect of exercise to lower night-time DBP was not apparent in the presence of T (T+Ex: -0.4 vs. P+NEx: +0.7 mmHg, p > .05). Ex increased average 24-h pulse pressure (PP, exercise*time, p = .022), largely during daytime hours (exercise*time, p = .013). CONCLUSIONS: There was a main effect of T to increase 24-h SBP, primarily seen when T was combined with Ex. Exercise alone decreased 24-h and night-time DBP; an effect attenuated by T. BP should be carefully assessed and monitored, when prescribing T treatment to middle-aged and older men, especially when combined with exercise training.

Toward a theory-based specification of non-pharmacological treatments in aging and dementia: Focused reviews and methodological recommendations.

INTRODUCTION: Non-pharmacological treatments (NPTs) have the potential to improve meaningful outcomes for older people at risk of, or living with dementia, but research often lacks methodological rigor and continues to produce mixed results. METHODS: In the current position paper, experts in NPT research have specified treatment targets, aims, and ingredients using an umbrella framework, the Rehabilitation Treatment Specification System. RESULTS: Experts provided a snapshot and an authoritative summary of the evidence for different NPTs based on the best synthesis efforts, identified main gaps in knowledge and relevant barriers, and provided directions for future research. Experts in trial methodology provide best practice principles and recommendations for those working in this area, underscoring the importance of prespecified protocols. DISCUSSION: We conclude that the evidence strongly supports various NPTs in relation to their primary targets, and discuss opportunities and challenges associated with a unifying theoretical framework to guide future efforts in this area.

An Internet-Based Intervention Augmented With a Diet and Physical Activity Consultation to Decrease the Risk of Dementia in At-Risk Adults in a Primary Care Setting: Pragmatic Randomized Controlled Trial.

BACKGROUND: There is a need to develop interventions to reduce the risk of dementia in the community by addressing lifestyle factors and chronic diseases over the adult life course. OBJECTIVE: This study aims to evaluate a multidomain dementia risk reduction intervention, Body Brain Life in General Practice (BBL-GP), targeting at-risk adults in primary care. METHODS: A pragmatic, parallel, three-arm randomized trial involving 125 adults aged 18 years or older (86/125, 68.8% female) with a BMI of ≥25 kg/m2 or a chronic health condition recruited from general practices was conducted. The arms included (1) BBL-GP, a web-based intervention augmented with an in-person diet and physical activity consultation; (2) a single clinician-led group, Lifestyle Modification Program (LMP); and (3) a web-based control. The primary outcome was the Australian National University Alzheimer Disease Risk Index Short Form (ANU-ADRI-SF). RESULTS: Baseline assessments were conducted on 128 participants. A total of 125 participants were randomized to 3 groups (BBL-GP=42, LMP=41, and control=42). At immediate, week 18, week 36, and week 62 follow-ups, the completion rates were 43% (18/42), 57% (24/42), 48% (20/42), and 48% (20/42), respectively, for the BBL-GP group; 71% (29/41), 68% (28/41), 68% (28/41), and 51% (21/41), respectively, for the LMP group; and 62% (26/42), 69% (29/42), 60% (25/42), and 60% (25/42), respectively, for the control group. The primary outcome of the ANU-ADRI-SF score was lower for the BBL-GP group than the control group at all follow-ups. These comparisons were all significant at the 5% level for estimates adjusted for baseline differences (immediate: difference in means -3.86, 95% CI -6.81 to -0.90, P=.01; week 18: difference in means -4.05, 95% CI -6.81 to -1.28, P<.001; week 36: difference in means -4.99, 95% CI -8.04 to -1.94, P<.001; and week 62: difference in means -4.62, 95% CI -7.62 to -1.62, P<.001). CONCLUSIONS: A web-based multidomain dementia risk reduction program augmented with allied health consultations administered within the general practice context can reduce dementia risk exposure for at least 15 months. This study was limited by a small sample size, and replication on a larger sample with longer follow-up will strengthen the results. TRIAL REGISTRATION: Australian clinical trials registration number (ACTRN): 12616000868482; https://anzctr.org.au/ACTRN12616000868482.aspx.

A randomized controlled trial of physical activity with individual goal-setting and volunteer mentors to overcome sedentary lifestyle in older adults at risk of cognitive decline: the INDIGO trial protocol.

BACKGROUND: Increasing physical activity (PA) effectively in those who are inactive is challenging. For those who have subjective memory complaints (SMC) or mild cognitive impairment (MCI) this is a greater challenge necessitating the need for more engaging and innovative approaches. The primary aim of this trial is to determine whether a home-based 6-month PA intervention with individual goal-setting and peer mentors (GM-PA) can significantly increase PA levels in insufficiently active older adults at increased risk of developing Alzheimer's disease (AD). METHODS: Community living 60-80 year olds with SMC or MCI who do not engage in more than 60 min per week of moderate intensity PA will be recruited from memory clinics and the community via media advertisements to participate in this randomized, single-blind controlled trial. All participants will receive an individually tailored home-based PA program of 150 min of moderate intensity walking/week for 6 months. The intervention group will undertake individual goal-setting and behavioral education workshops with mentor support via telephone (GM-PA). Those randomized to the control group will have standard education workshops and Physical Activity Liaison (PAL) contact via telephone (CO-PA). Increase in PA is the primary outcome, fitness, cognitive, personality, demographic and clinical parameters will be measured and a health economic analysis performed. A saliva sample will be collected for APOE e4 genotyping. All participants will have a goal-setting interview to determine their PA goals. Active volunteers aged 50-85 years will be recruited from the community randomized and trained to provide peer support as mentors (intervention group) or PALS (control group) for the 6-month intervention. Mentors and PALS will have PA, exercise self-efficacy and mentoring self-efficacy measured. Participants in both groups are asked to attend 3 workshops in 6 months. At the first workshop, they will meet their allocated Mentor or PAL who will deliver their respective programs and support via 6 telephone calls during the intervention. DISCUSSION: If the GM-PA program is successful in increasing the PA levels of the target group it will potentially provide another strategy and community resource that can be translated into practice. TRIAL REGISTRATION: Australia New Zealand Clinical Trials Registry ACTRN12613001181796 . (29/10/2013) retrospectively registered.

Semi-automated hippocampal segmentation in people with cognitive impairment using an age appropriate template for registration.

BACKGROUND: To evaluate a new semi-automated segmentation method for calculating hippocampal volumes and to compare results with standard software tools in a cohort of people with subjective memory complaints (SMC) and mild cognitive impairment (MCI). METHODS: Data from 58 participants, 39 with SMC (17 male, 22 female, mean age 72.6) and 19 with MCI (6 male, 13 female, mean age 74.3), were analyzed. For each participant, T1-weighted images were acquired using an MPRAGE sequence on a 3 Tesla MRI system. Hippocampal volumes (left, right, and total) were calculated with a new, age appropriate registration template, based on older people and using the advanced software tool ANTs (Advanced Normalization Tools). The results were compared with manual tracing (seen as the reference standard) and two widely accepted automated software tools (FSL, FreeSurfer). RESULTS: The hippocampal volumes, calculated by using the age appropriate registration template were significantly (P < 0.05) more accurate (mean volume accuracy more than 90%) than those obtained with FreeSurfer and FSL (both less than 70%). Dice coefficients for the hippocampal segmentations with the new template method (75.3%) were slightly, but significantly (P < 0.05) higher than those from FreeSurfer (72.4%). CONCLUSION: These results suggest that an age appropriate registration template might be a more accurate alternative to calculate hippocampal volumes when manual segmentation is not feasible.

Impact of Water- and Land-Based Exercise Training on Risk Factors and Vascular Function in Middle-Aged and Older Men and Women.

INTRODUCTION: Exercise improves vascular function, but it is unclear whether benefits are mediated by traditional cardiovascular risk factors or whether sex differences in training effects exist in older adults. We hypothesized that exercise would improve cardiovascular risk factors, that males and females would benefit similarly, and that improvements in risk factors would correlate with changes in vascular function. METHODS: Seventy-two healthy middle-aged/older adults (age, 62 ± 7 yr; 26%♂) were randomized to a land-walking ( n = 23), water-walking ( n = 25), or a nonexercise control group (C; n = 23). The exercise groups undertook supervised and monitored training three times a week for 50 min per session, across 24 wk. Blood pressure, body composition (dual x-ray absorptiometry), blood lipids and glucose, and flow-mediated brachial artery dilation were assessed in all participants at weeks 0 and 24. To maximize power for sex differences and correlation analyses, we pooled the training groups (land-walking + water-walking). RESULTS: Training prevented increases in LDL and total cholesterol/HDL ratio observed in the nonexercise control group. No group by time interactions were observed for other risk factors. Sex differences in training effects existed for visceral fat (-187 ± 189 g♂ vs -15 ± 161 g♀; P = 0.006) and lean mass (-352 ± 1045 g♂ vs 601 ± 1178 g♀; P = 0.008). Improvement in flow-mediated brachial artery dilation was correlated with decreased waist girth ( r = -0.450, P = 0.036), but not with other risk factors. CONCLUSIONS: Exercise training prevented deterioration in lipid levels, whereas sex differences existed for body composition changes with training. Improvement in vascular function was not dependent on changes in risk factors in middle-aged/older adults, suggesting that artery health may be dependent on other exercise-related stimuli.

Community-based dementia risk management and prevention program for Aboriginal Australians (DAMPAA): a randomised controlled trial study protocol.

INTRODUCTION: Aboriginal and Torres Strait Islander peoples are the First Peoples of Australia. Up to 45% of dementia in these populations is due to potentially modifiable risk factors. The Dementia Prevention and Risk Management Program for Aboriginal Australians (DAMPAA) is an Aboriginal Health Practitioner led programme that aims to reduce cognitive decline and functional impairment in older Aboriginal people. METHODS: Design: DAMPAA is a multisite, randomised controlled trial aiming to deliver and evaluate a culturally appropriate risk factor management programme. POPULATION: Community-dwelling Aboriginal people aged 45-90 years. INTERVENTION: Participants will be randomly assigned to either usual care (control) or to a group programme comprising exercise and health education yarning sessions and pharmacist-delivered medication reviews delivered over a 12-month period. PRIMARY OUTCOME: Cognitive function (Kimberley Indigenous Cognitive Assessment (KICA)-Cog score), daily function (KICA-Activities of Daily Living (ADL) score) and quality of life (Good Spirit, Good Life and EQ-5D-5L scores). SECONDARY OUTCOMES: Process evaluation interviews, cardiovascular risk factors, falls and death. Process evaluation will be conducted with qualitative methods. Quantitative outcomes will be analysed with generalised linear mixed models. ETHICS AND DISSEMINATION: The study was approved by the Western Australian Aboriginal Health Ethics Committee and the University of Western Australia Human Research Ethics Committee. Study results will be published in peer-reviewed journals and presented at scientific meetings. We will also develop and disseminate a comprehensive DAMPAA toolkit for health services. The study's findings will guide future prevention strategies and outline a comprehensive process evaluation that may be useful in other Aboriginal health research to contextualise findings.

Impact of provision of abdominal aortic calcification results on fruit and vegetable intake: 12-week randomized phase 2 controlled trial.

Provision of non-invasive vascular imaging results to individuals has been shown to improve cardiovascular disease risk factor control: its impact on diet remains uncertain. In this two-arm, single-blind, parallel, 12-week randomized controlled trial, 240 participants, 57.5% females aged 60-80 y had abdominal aortic calcification and clinical assessments performed at a hospital clinic. Participants were randomized 1:1 to receive (intervention n = 121) or not (control n = 119) their calcification results. Both groups received educational resources on cardiovascular disease risk control and were unblinded to the intervention. Outcome measures were performed at baseline and 12 weeks. The primary outcomes of the study were changes in fruit and vegetable intake measures over 12 weeks assessed using plasma carotenoid concentrations (biomarkers of FV intake) and a food frequency questionnaire. Secondary outcomes included 12-week changes in other aspects of the diet, physical activity, body weight, blood pressure, heart rate, lipid profile, glucose concentrations, estimated cardiovascular disease risk score, and medication use. Between-group differences were tested using linear mixed-effects regression. There were no between-group differences in the primary outcomes at 12 weeks: plasma carotenoids (mean difference +0.03 µg/mL [95%CI -0.06, 0.13]) and fruit and vegetable intakes (+18 g/d [-37, 72]). However, the provision of calcification results led to between-group differences in serum total (-0.22 mmol/L [-0.41, -0.04]) and non-HDL (-0.19 mmol/L [-0.35, -0.03]) cholesterol, and estimated cardiovascular disease risk score (-0.24% [-0.47, -0.02]). No between-group differences were seen for other secondary outcomes. In this work, providing vascular imaging results did not improve diet but did improve some cardiovascular disease risk factors (Australian and New Zealand Clinical Trials Registry ACTRN12618001087246).

The FABS trial: a randomised control trial of the effects of a 6-month physical activity intervention on adherence and long-term physical activity and self-efficacy in older adults with memory complaints.

OBJECTIVE: The aim of this study is to assess in older adults with memory complaints, the effects of a 6-month home-based physical activity (PA) intervention on short-term adherence, short and long-term self-efficacy and the predictors of adherence. METHODS: Participants with memory complaints with or without mild cognitive impairment (MCI) were recruited from Perth, Western Australia between May 2004 and July 2006 and randomly assigned to a control or an intervention group. The intervention group received a 6-month PA programme and recorded sessions on a diary. Pedometer readings, questionnaires, and physical and cognitive measures were completed at 0, 6, 12 and 18 months. RESULTS: One hundred and seventy participants started the study. Retention rates were similar for both groups at all time-points however retention was higher for men than women (P<0.01). Adherence to the prescribed PA was 72.8% (95% CI, 70.8 74.9%). Men had higher adherence rate than women (P<0.001). Those with and without MCI had similar adherence. Compared to controls self-efficacy was higher in the intervention group after 6 months only (P<0.01). CONCLUSIONS: Older adults with memory complaints, with or without MCI, can successfully participate in and enjoy home-based PA programmes. Long-term adherence to such interventions may require continued support and increased self-efficacy. ( TRIAL REGISTRATION: ACTRN012605000136606.).

Physical Activity for Cognitive Health: A Model for Intervention Design for People Experiencing Cognitive Concerns and Symptoms of Depression or Anxiety.

BACKGROUND: People experiencing cognitive concerns and symptoms of depression or anxiety are at risk for Alzheimer's disease and dementia. We know physical activity can benefit cognition but understanding how to best support engagement is an ongoing challenge. Evidence-based conceptual models of factors underpinning physical activity engagement in target populations can inform intervention tailoring to address this challenge. OBJECTIVE: This study (part of a pragmatic physical activity implementation trial) aimed to develop a specified model of physical activity engagement in people experiencing depressive or anxiety symptoms and cognitive concerns, to enable optimized dementia risk reduction intervention tailoring. METHODS: We employed a qualitative design, triangulating data from three sources: semi-structured individual interviews with people experiencing cognitive concerns and mild to moderate depressive or anxiety symptoms; review of published evidence; and the Capability, Opportunity and Motivation system of behavior, an existing behavioral science model. Findings were integrated to develop a contextualized model of mechanisms of action for optimizing engagement. RESULTS: Twenty-one participants were interviewed, and 24 relevant papers included. Convergent and complementary themes extended understanding of intervention needs. Findings highlighted emotional regulation, capacities to enact intentions despite barriers, and confidence in existing skills as areas of population-specific need that have not previously been emphasized. The final model provides specificity, directionality, and linked approaches for intervention tailoring. CONCLUSION: This study demonstrated that people experiencing cognitive concerns and symptoms of depression or anxiety require different interventions to improve physical activity engagement. This novel model can enable more precise intervention tailoring, and, ultimately, benefits for a key at-risk population.

Protocol for a randomized controlled trial evaluating the effect of physical activity on delaying the progression of white matter changes on MRI in older adults with memory complaints and mild cognitive impairment: the AIBL Active trial.

BACKGROUND: Older adults free of dementia but with subjective memory complaints (SMC) or mild cognitive impairment (MCI) are considered at increased risk of cognitive decline. Vascular risk factors (VRF), including hypertension, heart disease, smoking, hypercholesterolemia and lack of physical activity (PA) have been identified as modifiable risk factors contributing to cognitive decline, and white matter hyperintensities (WMH) are associated with VRF, SMC and cognitive impairment. Findings from a growing number of clinical trials with older adults are providing strong evidence for the benefits of physical activity for maintaining cognitive function, but few studies are investigating these benefits in high-risk populations. The aim of AIBL Active is to determine whether a 24-month physical activity program can delay the progression of white matter changes on magnetic resonance imaging (MRI). METHODS/DESIGN: This single-blind randomized controlled trial (RCT) is offered to 156 participants, aged 60 and older, in the Melbourne arm of the Australian Imaging Biomarkers and Lifestyle Flagship Study of Aging (AIBL). Participants must have SMC with or without MCI and at least one VRF. The PA intervention is a modification of the intervention previously trialed in older adults with SMC and MCI (Fitness for the Ageing Brain Study). It comprises 24 months of moderate, home-based PA (150 minutes per week) and a behavioral intervention package. The primary outcome measure will be change in WMH after 24 months on MRI. Cognition, quality of life, functional fitness, level of physical activity, plasma biomarkers for cerebrovascular disease and amyloid positron emission tomography (PET) imaging comprise secondary measures. DISCUSSION: Currently, there is no effective pharmacological treatment available to delay cognitive decline and dementia in older adults at risk. Should our findings show that physical activity can slow down the progression of WMH, this RCT would provide an important proof of concept. Since imbedded in AIBL this RCT will also be able to investigate the interaction between vascular and Alzheimer's disease pathologies. TRIAL REGISTRATION: Australia New Zealand Clinical Trials Registry ACTRN12611000612910.

Factors Influencing Long-Term Physical Activity Maintenance: A Qualitative Evaluation of a Physical Activity Program for Inactive Older Adults at Risk of Cognitive Decline: The INDIGO Follow-Up Study.

BACKGROUND: Physical inactivity is a modifiable risk factor for dementia, but there remains a research translation gap in effective physical activity (PA) implementation, particularly in the longer-term. The INDIGO trial investigated the effectiveness of a six-month PA intervention for inactive older adults at risk of cognitive decline with subjective cognitive decline or mild cognitive impairment. OBJECTIVE: This follow-up study aimed to collect feedback from INDIGO participants about their experience of involvement in the trial, including barriers and enablers to longer-term maintenance of PA. METHODS: A qualitative study using semi-structured individual interviews was conducted and transcripts analyzed thematically. All INDIGO trial completers were invited, with 29 participating (follow-up period 27-66 months post-baseline). RESULTS: At long-term follow-up, participants described INDIGO trial participation as beneficial. The theme of "Motivation" (subthemes: structure and accountability, knowledge and expected benefits, preferences and motivation, tools) followed by "Situation" (subthemes: environment and time, social aspects, aging and physical health) appeared to be critical to PA "Action". Most participants had a positive view of goal-setting and peer mentoring/support, but there was some polarization of opinion. Key factors to longer-term "Maintenance" of PA were self-efficacy and perceived benefits, habit formation, and for some participants, enjoyment. CONCLUSION: PA interventions for older adults at risk of cognitive decline should include behavior change techniques tailored to the individual. Effective techniques should focus on "Motivation" (particularly structure and accountability) and "Situation" factors relevant to individuals with the aim of developing self-efficacy, habit formation, and enjoyment to increase the likelihood of longer-term PA maintenance.

Exercise interventions to reduce anxiety in mid-life and late-life anxiety disorders and subthreshold anxiety disorder: a systematic review.

Background: Anxiety disorders are highly prevalent and cause significant distress, disability, and cost. Medication adverse effects and interactions increase in mid-life and late-life, highlighting the need for effective non-pharmacological interventions. Objectives: We aimed to evaluate the extent of evidence supporting exercise interventions for anxiety and subthreshold anxiety disorders in mid-life and late-life. Design: Systematic review. Data Sources and Methods: We searched MEDLINE, PsycINFO, Embase, Emcare, Ovid Nursing, CINAHL Plus, Cochrane Library, Health Collection, Humanities & Social Sciences Collection, and https://clinicaltrials.gov databases for trials published January 1994-May 2019. Randomised controlled trials of exercise interventions involving aerobic exercise or resistance training for adults aged 40 years and above with anxiety or subthreshold anxiety disorders in residential or health settings were identified. The primary outcome was change in anxiety. We excluded trials including participants aged below 40 years, participants with diagnosis of separation anxiety, selective mutism, obsessive-compulsive disorder, acute stress disorder and post-traumatic stress disorder, and head-to-head comparisons of interventions. Trial quality was assessed using the Cochrane Risk of Bias Tool and evidence synthesised in narrative form. Results: Four trials totalling 132 participants met inclusion criteria, although some had methodological limitations. Interventions included a home-based resistance training intervention, supervised group-based aerobic intervention, Tai Chi intervention, and supervised group-based aerobic and strength intervention. Three trials included late-life participants and the fourth mid-life. Three trials demonstrated greater reductions in anxiety in the intervention group compared with control. The fourth trial showed pre-post reductions in anxiety in both groups, with between-group difference not reaching statistical significance. Conclusion: There is limited supportive evidence suggesting that exercise interventions have potential to be effective, feasible and safe non-pharmacological interventions for anxiety and subthreshold anxiety disorders in mid-life and late-life. The heterogeneity, limited number and high risk of bias of some trials meant that we were not able to conduct a meta-analysis. Tailoring of interventions may improve uptake and reduce dropout. The paucity of research in this area with only four included trials demonstrates the urgent need for future and larger trials to provide proof of concept, data about effective types and doses of exercise interventions, and guidance to community, clinical, and public health services.

The Impact of 6-Month Land versus Water Walking on Cerebrovascular Function in the Aging Brain.

INTRODUCTION: To examine the hypothesis that exercise training induces adaptation in cerebrovascular function, we recruited 63 older adults (62 ± 7 yr, 46 females) to undertake 24 wk of either land walking or water walking, or participate in a nonexercise control group. This is the first multi-interventional study to perform a comprehensive assessment of cerebrovascular function in response to longer term (6-month) training interventions, including water-based exercise, in older healthy individuals. METHODS: Intracranial blood flow velocities (middle cerebral artery (MCAv) and posterior cerebral artery) were assessed at rest and in response to neurovascular coupling, hypercapnic reactivity, and cerebral autoregulation. RESULTS: We observed no change in resting MCAv in response to either training intervention (pre vs post, mean (95% confidence interval), land walking: 65 (59-70) to 63 (57-68) cm·s-1, P = 0.33; water walking: 63 (58-69) to 61 (55-67) cm·s-1, P = 0.92) compared with controls and no change in neurovascular coupling (land walking: P = 0.18, water walking: P = 0.17). There was a significant but modest improvement in autoregulatory normalized gain after the intervention in the water-walking compared with the land-walking group (P = 0.03). Hypercapnic MCAv reactivity was not different based on exercise group (land: P = 087, water: P = 0.83); however, when data were pooled from the exercise groups, increases in fitness were correlated with decreases in hypercapnic reactivity (r2 = 0.25, P = 0.003). CONCLUSIONS: Although exercise was not associated with systematic changes across multiple domains of cerebrovascular function, our data indicate that exercise may induce modest changes in autoregulation and CO2 reactivity. These findings should encourage further studies of the longer-term implications of exercise training on cerebrovascular health.

The Support Person's Preferences and Perspectives of Physical Activity Programs for Older Adults With Cognitive Impairment.

Objectives: Physical activity (PA) is beneficial for older adults' cognition. There is limited research investigating perspectives of support persons (SPs) of next-of-kins (NOKs) with cognitive impairment. This exploratory study aimed to investigate perspectives of SPs of older adults with Alzheimer's Dementia (AD) or Mild Cognitive Impairment (MCI). Methods: A telephone survey of 213 SPs of NOKs from the Australian Imaging, Biomarkers and Lifestyle Flagship Study of Ageing (AIBL) was undertaken to quantitatively assess SPs' beliefs and knowledge about PA benefits, current PA level of their NOK, and PA program preferences. The contribution of age, gender, diagnosis and mental health symptoms was assessed using multiple logistic regression analyses. Results: Many SPs were aware of PA benefits for memory (64%) and believed it would help their NOK (72%). Older SP age was associated with less awareness of benefits (p = 0.016). SPs caring for male NOKs were more likely to believe that PA would be helpful than those caring for female NOKs (p = 0.049). NOK AD diagnosis (rather than MCI) (p = 0.014), older age (p = 0.005) and female gender (p = 0.043) were associated with lower PA levels. SPs were mixed regarding preference for their NOKs to participate in individual (45%) or group (54%) PA. Many SPs wanted to participate in PA with their NOK (63%). Conclusions: The results highlight that SPs have high levels of awareness of the cognitive benefits of PA, and describe their preferences regarding PA programs. The findings provide new information to inform targeted public health messaging, PA prescribers and providers, and future research directions.

A Randomized Controlled Trial on the Effects of a 6-Month Home-Based Physical Activity Program with Individual Goal-Setting and Volunteer Mentors on Physical Activity, Adherence, and Physical Fitness in Inactive Older Adults at Risk of Cognitive Decline: The INDIGO Study.

BACKGROUND: Increasing physical activity (PA) in those who have memory concerns requires innovative approaches. OBJECTIVE: To compare in this randomized controlled trial (RCT) the effects on PA, adherence, and fitness of two approaches to deliver a 6-month home-based PA program in older, inactive individuals at risk of cognitive decline. METHODS: Individuals (n = 52) aged 60-85 years, inactive with mild cognitive impairment or subjective cognitive decline were recruited from the community and memory clinics. Randomization was to 6 months of 150 min/week moderate intensity PA with either: goal-setting with mentor support; or education and peer contact. A subset of participants (n = 36) continued for a further 6 months. PA, moderate and vigorous PA, and secondary outcomes, fitness, goal performance/satisfaction and self-efficacy were assessed at baseline, 6 and 12 months. Modelling of primary and secondary outcomes was conducted with linear mixed models. RESULTS: Participants were mean age (±sd) 70.1 (6.4) years. Six-month retention was 88.5%(n = 46). No significant between-group differences were observed for PA or fitness. Post-hoc combined group data showed a significant, moderate-large effect size increase in PA with time. PA increased by a mean 1,662 (943, 2383) steps/day (95%CI) and 1,320 (603, 2037) steps/day at 6 and 12 months (p < 0.001). Median (quartiles Q1-Q3) 6 and 6-12 month combined group adherence was 88.9 (74.4-95.7)%and 84.6 (73.9-95.4)%respectively. CONCLUSION: In this target group, no differences were detected between groups both intervention strategies were highly effective in increasing PA and fitness.

Effects of Land versus Water Walking Interventions on Vascular Function in Older Adults.

PURPOSE: Endothelial dysfunction is an early and integral atherogenic event. Interventions that improve endothelial function also reduce cardiovascular risk. Due largely to the direct hemodynamic effects of repetitive exercise on the artery wall, exercise training has shown to enhance endothelial function. Land walking (LW) and water walking (WW) induce distinct hemodynamic responses, so the comparison of their effects provides an approach to study shear stress effects on endothelial function. We hypothesized that LW and WW training would have different effects on peripheral artery endothelial function. METHODS: Fifty-one sedentary, older (age = 61.9 ± 6.6 yr, 23.5% male) individuals were randomized into one of three groups: control (n = 16), or one of two exercise groups consisting of 3 × 50 min supervised and individually tailored walking sessions per week for 24 consecutive weeks, performed either on LW (n = 17) or on WW (n = 18). Brachial artery endothelial function (flow-mediated dilation) and smooth muscle cell function (glyceryl trinitrate administration) were tested in all participants before (week 0) and after (week 24) the intervention. RESULTS: Differences were apparent in flow-mediated dilation change between the LW group (week 0, 5.39% ± 0.71%, to week 24, 7.77% ± 0.78%; P = 0.009) and the control group (week 0, 5.87% ± 0.73%, to week 24, 5.78% ± 0.78%). No differences in artery dilation response were found after glyceryl trinitrate administration (all P > 0.05). CONCLUSION: This study suggests that 6-month center-based LW may be superior to WW in terms of improvement in arterial endothelial function in older sedentary individuals.

Effects of a physical activity intervention on brain atrophy in older adults at risk of dementia: a randomized controlled trial.

Lack of physical activity is a risk factor for dementia, however, the utility of interventional physical activity programs as a protective measure against brain atrophy and cognitive decline is uncertain. Here we present the effect of a randomized controlled trial of a 24-month physical activity intervention on global and regional brain atrophy as characterized by longitudinal voxel-based morphometry with T1-weighted MRI images. The study sample consisted of 98 participants at risk of dementia, with mild cognitive impairment or subjective memory complaints, and having at least one vascular risk factor for dementia, randomized into an exercise group and a control group. Between 0 and 24 months, there was no significant difference detected between groups in the rate of change in global, or regional brain volumes.

Land- versus water-walking interventions in older adults: Effects on body composition.

OBJECTIVES: Increasing physical activity is a priority worldwide, including for older adults who may have difficulty performing traditional forms of exercise, and for whom retention of muscle mass is an important consideration. Water-based exercise may provide an alternative if benefits are comparable. We compared the impact on body composition of 24-week water- versus land-walking interventions in healthy but inactive older adults. DESIGN: Randomised, controlled trial. METHODS: 72 participants (62.5±6.8yr) were randomised to a land-walking (LW), water-walking (WW) or control (C) group in a supervised centre-based program. The exercise groups trained 3 times/week at matched intensity (%HRR), increasing from 40-45% to 55-65% heart rate reserve (HRR). Height, weight, body mass index (BMI), waist and hip girths were recorded; dual X-ray absorptiometry (DXA) provided fat and lean tissue masses. Participants were re-assessed 24 weeks after completion of the intervention. RESULTS: There were no significant changes in body mass or BMI following either exercise protocol, however central adiposity was reduced in both exercise groups, and the WW group increased lower limb lean mass. These benefits did not persist over the follow-up period. CONCLUSIONS: Exercise can confer beneficial effects on body composition which are not evident when examining weight or BMI. Both WW and LW improved body composition. Water walking can be recommended as an exercise strategy for this age group due to its beneficial effects on body composition which are similar to, or exceed, those associated with land-walking. For benefits to persist, it appears that exercise needs to be maintained.