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ObjectiveAge-related hippocampal atrophy is associated with memory loss in older adults, and certain hippocampal subfields are more vulnerable to age-related atrophy than others. Cardiorespiratory fitness (CRF) may be an important protective factor for preserving hippocampal volume, but little is known about how CRF relates to the volume of specific hippocampal subfields, and whether associations between CRF and hippocampal subfield volumes are related to episodic memory performance. To address these gaps, the current study evaluates the associations among baseline CRF, hippocampal subfield volumes, and episodic memory performance in cognitively unimpaired older adults from the Investigating Gains in Neurocognition Trial of Exercise (IGNITE) (NCT02875301).MethodsParticipants (N = 601, ages 65–80, 72% female) completed assessments including a graded exercise test measuring peak oxygen comsumption (VO2peak) to assess CRF, cognitive testing, and high-resolution magnetic resonance imaging of the hippocampus processed with Automated Segmentation of Hippocampal Subfields (ASHS). Separate linear regression models examined whether CRF was associated with hippocampal subfield volumes and whether those assocations were moderated by age or sex. Mediation models examined whether hippocampal volumes statistically mediated the relationship between CRF and episodic memory performance. Covariates included age, sex, years of education, body mass index, estimated intracranial volume, and study site.ResultsHigher CRF was significantly associated with greater total left (B = 5.82, p = 0.039) and total right (B = 7.64, p = 0.006) hippocampal volume, as well as greater left CA2 (B = 0.14, p = 0.022) and dentate gyrus (DG; B = 2.34, p = 0.031) volume, and greater right CA1 (B = 3.99, p = 0.011), CA2 (B = 0.15, p = 0.002), and subiculum (B = 1.56, p = 0.004) volume. Sex significantly moderated left DG volume (B = −4.26, p = 0.017), such that the association was positive and significant only for males. Total left hippocampal volume [indirect effect = 0.002, 95% CI (0.0002, 0.00), p = 0.027] and right subiculum volume [indirect effect = 0.002, 95% CI (0.0007, 0.01), p = 0.006] statistically mediated the relationship between CRF and episodic memory performance.DiscussionWhile higher CRF was significantly associated with greater total hippocampal volume, CRF was not associated with all underlying subfield volumes. Our results further demonstrate the relevance of the associations between CRF and hippocampal volume for episodic memory performance. Finally, our results suggest that the regionally-specific effects of aging and Alzheimer’s disease on hippocampal subfields could be mitigated by maintaining higher CRF in older adulthood.

Background/objectiveTo examine the cognitive benefits of 6 months of prescribed intermittent exercise (10-min bouts totaling 150 weekly minutes) in community-dwelling older adults, comparing effects of low-intensity movement (LIM) and moderate-intensity aerobic exercise (aerobic exercise; AE) training; and exploring biological mechanisms of exercise-related cognitive improvement.MethodTwenty-five adults (>60 years old) participated in a 6-month controlled trial and were randomized into LIM or AE intermittent training. Cognition was assessed using a neuropsychological test battery including the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), California Verbal Learning Test, 2nd Edition (CVLT-II), and Delis-Kaplan Executive Function System (D-KEFS). Neuroimaging measures were collected using a 7 T human MRI scanner. Serologic neurotrophic and inflammatory factors were analyzed using Luminex multiplex assays [brain derived neurotrophic factor (BDNF); vascular endothelial growth factor (VEGF)]; interleukin-6 (IL-6), C-reactive protein (CRP), plasminogen activator inhibitor (PAI-1).ResultsLIM and AE intermittent training had dissociable effects on cognition, with LIM resulting in improved learning and memory and AE resulting in improved executive functioning. Intervention groups differed on change in cognitive performance on CVLT-II learning and D-KEFS trail making test. Increase in right dorsolateral prefrontal cortex (DLPFC) surface area was linked to executive improvement (i.e., phonemic fluency) regardless of intervention group. A decline in circulating PAI-1 was linked to learning and memory improvement in response to LIM over 6 months.ConclusionModerate-intensity AE and LIM intermittent training likely have distinct cognitive benefits, though low-intensity activity is often included as a control group in exercise trials in aging.

IntroductionOlder adults are not protected from obesity, which has been linked to frailty, cognitive impairment, and other aging-related factors. Intensive lifestyle interventions have been shown to be effective for weight loss in older adults; however, these have typically been highly intensive and less feasible for dissemination. This analysis describes weight loss in a large-scale, commercially available, digital intervention in a subset of older adults.MethodsOlder adults (N = 20,443, males = 6,238; females = 14,205) between 65 and 85 years of age with overweight (43.3%) or obesity (46.7%) participated in an online, self-directed weight loss program. Behavioral-based content was delivered through weekly video lessons within an online platform that included weight and physical activity tracking, an online community, a reference library, and access to coaching support. Self-reported measures taken at the time of entry into the program were used for this analysis (demographics, height, body weight, and health status). Weight was reported across weeks of engagement in the curriculum.ResultsThe average weight loss was −3.15 kg (95% CI: [−3.20, −3.11]) at 15.5 weeks. Weight loss was significantly greater in male individuals (−3.79 kg [95% CI: −3.89, −3.71]) versus female individuals (−2.87 kg [95% CI: −2.94, −2.82]) (p < 0.001), with a similar engagement in curriculum weeks. Percent weight loss was statistically significant for all age categories (p < 0.05) and self-reported health conditions (p < 0.05).DiscussionShort-term weight loss was observed in older adults exposed to a low-touch, self-guided, and digital behavioral-based weight loss program. Weight loss was also observed even in the presence of various chronic health conditions.

Assessing physical activity is important in the treatment of chronic conditions, including chronic low back pain (cLBP). ActiGraph™, a widely used physical activity monitor, collects raw acceleration data, and processes these data through proprietary algorithms to produce physical activity measures. The purpose of this study was to replicate ActiGraph™ algorithms in MATLAB and test the validity of this method with both healthy controls and participants with cLBP. MATLAB code was developed to replicate ActiGraph™’s activity counts and step counts algorithms, to sum the activity counts into counts per minute (CPM), and categorize each minute into activity intensity cut points. A free-living validation was performed where 24 individuals, 12 cLBP and 12 healthy, wore an ActiGraph™ GT9X on their non-dominant hip for up to seven days. The raw acceleration data were processed in both ActiLife™ (v6), ActiGraph™’s data analysis software platform, and through MATLAB (2022a). Percent errors between methods for all 24 participants, as well as separated by cLBP and healthy, were all less than 2%. ActiGraph™ algorithms were replicated and validated for both populations, based on minimal error differences between ActiLife™ and MATLAB, allowing researchers to analyze data from any accelerometer in a manner comparable to ActiLife™.

PurposeTo determine if race and sex differences exist in determinants and timing of dropout among individuals enrolled in an exercise and/or caloric restriction intervention.MethodsA total of 947 adults with dyslipidemia (STRRIDE I, STRRIDE AT/RT) or prediabetes (STRRIDE-PD) were randomized to either inactive control or to 1 of 10 exercise interventions, ranging from doses of 8–23 kcal/kg/week, intensities of 50%–75% V˙O2 peak, and durations of 6–8 months. Two groups included resistance training, and one included a dietary intervention (7% weight loss goal). Dropout was defined as an individual withdrawn from the study, with the reasons for dropout aggregated into determinant categories. Timing of dropout was defined as the last session attended and aggregated into phases (i.e., “ramp” period to allow gradual adaptation to exercise prescription). Utilizing descriptive statistics, percentages were generated according to categories of determinants and timing of dropout to describe the proportion of individuals who fell within each category.ResultsBlack men and women were more likely to be lost to follow-up (Black men: 31.3% and Black women: 19.6%), or dropout due to work responsibilities (15.6% and 12.5%), “change of mind” (12.5% and 8.9%), transportation issues (6.3% and 3.6%), or reported lack of motivation (6.3% and 3.6%). Women in general noted lack of time more often than men as a reason for dropout (White women: 22.4% and Black women: 22.1%). Regardless of race and sex, most participants dropped out during the ramp period of the exercise intervention; with Black women (50%) and White men (37.1%) having the highest dropout rate during this period.ConclusionThese findings emphasize the importance of targeted retention strategies when aiming to address race and sex differences that exist in determinants and timing of dropout among individuals enrolled in an exercise and/or caloric restriction intervention.

Introduction: Klotho is a protein associated with protection from aging-related diseases and health conditions. Obesity is associated with lower Klotho concentrations. Thus, this secondary analysis of adults with obesity examined 1) the change in serum Klotho concentration in response to a behavioral weight loss intervention by the magnitude of weight loss achieved; and 2) the association among serum Klotho concentration and weight, body composition, and cardiorespiratory fitness.Methods: Participants were randomized to either diet alone (DIET), diet plus 150 min of physical activity per week (DIET + PA150), or diet plus 250 min of physical activity per week (DIET + PA250). Participants [n = 152; age: 45.0 ± 7.9 years; body mass index (BMI): 32.4 ± 3.8 kg/m2] included in this secondary analysis provided blood samples at baseline, 6-, and 12 months, and were classified by weight loss response (Responder: achieved ≥10% weight loss at 6 or 12 months; Non-responder: achieved

IntroductionThe social and behavioral effects of the COVID-19 pandemic have impacted the health and physiology of most people, including those never diagnosed with COVID-19. While the impact of the pandemic has been felt across the lifespan, its effects on cardiorespiratory fitness (commonly considered a reflection of total body health) of older adults and children may be particularly profound due to social distancing and stay-at-home advisories, as well as the closure of sport facilities and non-essential businesses. The objective of this investigation was to leverage baseline data from two ongoing clinical trials to determine if cardiorespiratory fitness and body mass index were different during COVID-19 relative to before COVID-19 in older adults and children.MethodsHealthy older individuals (N = 593; 65–80 years) and 200 typically developing children (8–10 years) completed a graded maximal exercise test and had their height and weight measured.ResultsResults revealed that older adults and children tested during COVID-19 had significantly lower cardiorespiratory fitness levels than those tested before COVID-19 shutdowns (older adults: 30% lower; children: 53% lower; p's ≤ 0.001). In addition, older adults and children tested during COVID-19 had significantly higher BMI (older adults: 31.34 ± 0.57 kg/m2, p = 0.004; children: 19.27 ± 0.44 kg/m2, p = 0.05) than those tested before COVID-19 shutdowns (older adults: 29.51 ± 0.26 kg/m2, children: 18.13 ± 0.35 kg/m2). However, these differences in BMI did not remain significant when controlling for cardiorespiratory fitness.DiscussionResults from this investigation indicate that the COVID-19 pandemic, and behavior changes taken to reduce potential exposure, may have led to lower cardiorespiratory fitness levels in older adults and children, as well as higher body mass index. These findings provide relevant public health information as lower cardiorespiratory fitness levels and higher body mass indexes recorded during the pandemic could have far-reaching and protracted health consequences. Public health guidance is needed to encourage physical activity to maintain cardiorespiratory fitness and healthy body composition.Clinical trial registrationOlder adults: https://clinicaltrials.gov/ct2/show/NCT02875301, identifier: NCT02875301; Children: https://clinicaltrials.gov/ct2/show/NCT03592238, identifier: NCT03592238.

ObjectiveThe apolipoprotein E ε4 (APOE ε4) allele and midlife obesity are independent risk factors for Alzheimer’s disease (AD). Both of these risk factors are also associated with differences in brain activation, as measured by blood oxygenation level-dependent (BOLD) responses, in the absence of detectable cognitive deficits. Although the presence of these risk factors may influence brain activity during working memory tasks, no study to date has examined whether the presence of the ε4 allele explains variation in working memory brain activity while matching for levels of overweight/obesity. The primary aim of this study was to determine whether the presence of the ε4 allele is associated with differences in task-functional magnetic resonance imaging (fMRI) brain activation in adults with overweight/obesity. We predicted that ε4 carriers would have greater brain activation in regions that support working memory.MethodsThis ancillary study included 48 (n = 24 APOE ε4 carriers; n = 24 APOE ε4 non-carriers), sedentary middle-aged adults (Mean age = 44.63 ± 8.36 years) with overweight/obesity (Mean BMI = 32.43 ± 4.12 kg/m2) who were matched on demographic characteristics. Participants were a subsample enrolled in 12-month randomized clinical trial examining the impact of energy-restricted diet and exercise on cardiovascular health outcomes. Participants completed a n-back working memory task with fMRI, which were completed within one month of the start of the intervention. Participants also underwent pseudo-continuous arterial spin labeling scans, a MRI measure of cerebral blood flow (CBF).ResultsCompared to non-ε4 carriers with overweight/obesity, ε4 carriers with overweight/obesity had lower fMRI brain activity in the middle frontal gyrus, pre and post central gyrus, supramarginal gyrus, superior temporal gyrus, lateral occipital cortex, and angular gyrus (z range = 2.52–3.56) during the n-back working memory task. Differences persisted even when controlling for CBF in these brain regions.ConclusionThese results indicate that presence of the APOE ε4 allele in middle-aged adults with overweight/obesity is related to altered brain activity during a working memory paradigm, which may confer risk for accelerated neurocognitive decline in late adulthood. Future research is needed to clarify the clinical implications of these findings in the context of risk for AD.

BackgroundThe single nucleotide polymorphism (SNP) rs9939609 in the fat mass and obesity associated fat mass and obesity associated gene (FTO) gene has been linked with increased BMI in adults. Higher BMI has been associated with poor brain health and may exert deleterious effects on neurocognitive health through cerebral hypoperfusion. However, it is unclear if there is a relationship between the FTO genotype and cerebral perfusion, or whether FTO genotype moderates the effects of weight loss on cerebral perfusion. Using data from a randomized controlled behavioral weight loss trial in adults with overweight and obesity, we tested (1) whether carriers of the A allele for FTO rs9939609 demonstrate different patterns of resting cerebral blood flow (rCBF) compared to T carriers, and (2) whether the FTO genotype moderates the effects of weight loss on rCBF. We hypothesized that carriers of the A allele would exhibit lower resting CBF in frontal brain areas compared to T/T homozygotes at baseline, and that intervention-induced weight loss may partially remediate these differences.Methods and resultsOne hundred and five adults (75.2% female, mean age 44.9 years) with overweight or obesity were included in the analyses. These participants represent a subsample of participants in a larger randomized controlled trial (NCT01500356). A resting pseudo-continuous arterial spin labeling (pCASL) scan was acquired to examine rCBF. Age, sex, and BMI were included as covariates. At baseline, A carriers had greater rCBF in a diffuse cluster extending into the brainstem, motor cortex, and occipital lobe, but lower perfusion in the temporal lobe. We found no evidence that FTO moderated the effect of the intervention group assignment on rCBF changes.ConclusionOverall, these results indicate that (a) individual variation in rCBF within a sample with overweight and obesity may be attributed to a common FTO variant, but (b) a weight loss intervention is effective at increasing rCBF, regardless of FTO genotype.

Summary Introduction Little is known about the influence of children in the home on physical activity and weight among adults in weight loss interventions. This study evaluated the association between number of children in the home, weight loss, and weight regain in a behavioural weight loss intervention, and whether those relationships were mediated in sequence by physical activity barriers and physical activity changes. Methods The sample included 267 participants from a randomized trial who had complete data on study variables. Variables at baseline, 6, and 18 months included physical activity barriers, objectively measured minutes of moderate‐to‐vigorous physical activity (MVPA), and objectively measured weight used to calculate percent weight loss (PWL) from baseline to 6 months and percent weight regained (PWG) from 6 to 18 months. Results A greater number of children in the home was associated with less PWL at 6 months. This relationship was mediated by greater baseline physical activity barriers and a smaller increase in MVPA at 6 months. The mediated effect was no longer significant when controlling for changes in dietary intake. There was no relationship between number of children and PWG from 6 to 18 months. Conclusions Parents may need unique intervention supports to overcome barriers to initiation of physical activity to help them reach optimal weight loss.

Summary Objective Left ventricular mass (LVM) is a clinical prognostic indicator of cardiovascular disease. Left ventricular mass is associated with body size (body mass index [BMI], weight, and body surface area [BSA]). This study examined if the association between body size (weight, BMI, and BSA) and LVM is influenced by body composition and cardiorespiratory fitness in adults who are overweight or obese. Methods This study included cross‐sectional baseline data from a randomized clinical trial. Participants included 379 adults (age, 45.6 ± 7.9 y) who were overweight or obese (BMI, 32.4 ± 3.8 kg·m−2). Measures included weight, height, BMI, BSA, body composition, cardiorespiratory fitness, and LVM by cardiac magnetic resonance imaging (CMR). Results Left ventricular mass was positively associated with weight, BMI, BSA, and fitness (P < .0001) and inversely associated with percent body fat (P < .0001). Stepwise multiple regression models showed that body fatness was inversely associated and cardiorespiratory fitness was positively associated with LVM even after considering weight, BMI, or BSA in the analyses. Conclusions These cross‐sectional findings support that in adults who are overweight or obese but otherwise relatively healthy, LVM is associated with both body composition and cardiorespiratory fitness. This may indicate the need to reduce body fatness and improve fitness for patients with obesity to enhance cardiovascular structure and function.

Abstract Introduction This study sought to determine whether 10 years of assignment to intensive lifestyle intervention (ILI) relative to diabetes support and education leads to better cognition. We examine intervention effects overall and among clinical subgroups, and report correlations between computer‐administered and interviewer‐administered cognitive batteries. Methods The Action for Health in Diabetes (Look AHEAD) was a 16‐site randomized controlled trial with overweight/obese individuals (aged 45–76) who had type 2 diabetes. The NIH Toolbox Cognition Battery tests developed to measure cognition across the lifespan were used to evaluate cognition. Results were compared with standard paper‐and‐pencil tests. The Toolbox and paper‐and‐pencil tests were administered an average of 10.9 years after randomization to 1002 participants. Results Toolbox measures significantly correlated with interviewer‐administered measures, with the strongest correlations between the Toolbox Fluid Cognition Composite and Trails B (r = −0.64, P .05 for all). Subgroup analyses identified different intervention effects within baseline body mass index groups for Picture Sequence Memory (P = .01), within baseline cardiovascular disease groups for Picture Vocabulary (P = .01) and Fluid Cognition Composite (P = .02) measures, and within baseline age groups for Picture Vocabulary (P = .02). Discussion Correlations between Toolbox and interviewer‐administered outcomes provide a measure of internal validity. Findings suggest no overall effect of the intervention on cognition and that an ILI resulting in weight loss may have negative implications for cognition in individuals aged ≥60, with previous history of cardiovascular disease, and those with body mass index ≥40.

The primary aims of this paper were (1) to evaluate the influence of intensive lifestyle weight loss and exercise intervention (ILI) compared with diabetes support and education (DSE) upon Heart Rate Recovery (HRR) from graded exercise testing (GXT) and (2) to determine the independent and combined effects of weight loss and fitness changes upon HRR. In 4503 participants (45–76 years) who completed 1 year of intervention, HRR was measured after a submaximal GXT to compare the influence of (ILI) with (DSE) upon HRR. Participants assigned to ILI lost an average 8.6% of their initial weight versus 0.7% in DSE group (P

BackgroundSedentary behavior (SB) is prevalent after abdominal cancer surgery, and interventions targeting perioperative SB could improve postoperative recovery and outcomes. We conducted a pilot study to evaluate the feasibility and preliminary effects of a real-time mobile intervention that detects and disrupts prolonged SB before and after cancer surgery, relative to a monitoring-only control condition. ObjectiveOur aim was to evaluate the feasibility and preliminary effects of a perioperative SB intervention on objective activity behavior, patient-reported quality of life and symptoms, and 30-day readmissions. MethodsPatients scheduled for surgery for metastatic gastrointestinal cancer (n=26) were enrolled and randomized to receive either the SB intervention or activity monitoring only. Both groups used a Fitbit smartwatch and companion smartphone app to rate daily symptoms and collect continuous objective activity behavior data starting from at least 10 days before surgery through 30 days post discharge. Participants in the intervention group also received prompts to walk after any SB bout that exceeded a prespecified threshold, with less frequent prompts on days that patients reported more severe symptoms. Participants completed end-of-study ratings of acceptability, and we also examined adherence to assessments and to walking prompts. In addition, we examined effects of the intervention on objective SB and step counts, patient-reported quality of life and depressive and physical symptoms, as well as readmissions. ResultsAccrual (74%), retention (88%), and acceptability ratings (mean overall satisfaction 88.5/100, SD 9.1) were relatively high. However, adherence to assessments and engagement with the SB intervention decreased significantly after surgery and did not recover to preoperative levels after postoperative discharge. All participants exhibited significant increases in SB and symptoms and decreases in steps and quality of life after surgery, and participants randomized to the SB intervention unexpectedly had longer maximum SB bouts relative to the control group. No significant benefits of the intervention with regard to activity, quality of life, symptoms, or readmission were observed. ConclusionsPerioperative patients with metastatic gastrointestinal cancer were interested in a real-time SB intervention and rated the intervention as highly acceptable, but engagement with the intervention and with daily symptom and activity monitoring decreased significantly after surgery. There were no significant effects of the intervention on step counts, patient-reported quality of life or symptoms, and postoperative readmissions, and there was an apparent adverse effect on maximum SB. Results highlight the need for additional work to modify the intervention to make reducing SB and engaging with mobile health technology after abdominal cancer surgery more feasible and beneficial. Trial RegistrationClinicalTrials.gov NCT03211806; https://tinyurl.com/3napwkkt