Age and beta amyloid deposition impact gait speed, stride length, and gait smoothness while transitioning from an even to an uneven walking surface in older adults.

BACKGROUND: Capturing a measure of movement quality during a complex walking task may indicate the earliest signs of detrimental changes to the brain due to beta amyloid (Aß) deposition and be a potential differentiator of older adults at elevated and low risk of developing Alzheimer's disease. This study aimed to determine: 1) age-related differences in gait speed, stride length, and gait smoothness while transitioning from an even to an uneven walking surface, by comparing young adults (YA) and older adults (OA), and 2) if gait speed, stride length, and gait smoothness in OA while transitioning from an even to an uneven walking surface is influenced by the amount of Aß deposition present in an OA's brain. METHODS: Participants included 56 OA (>70 years of age) and 29 YA (25-35 years of age). In OA, Aß deposition in the brain was quantified by PET imaging. All participants completed a series of cognitive assessments, a functional mobility assessment, and self-report questionnaires. Then participants performed two sets of walking trials on a custom-built walkway containing a mixture of even and uneven surface sections, including three trials with a grass uneven surface and three trials with a rocks uneven surface. Gait data were recorded using a wireless inertial measurement unit system. Stride length, gait speed, and gait smoothness (i.e., log dimensionless lumbar jerk) in the anteroposterior (AP), mediolateral (ML), and vertical (VT) directions were calculated for each stride. Outcomes were retained for five stride locations immediately surrounding the surface transition. RESULTS: OA exhibited slower gait (Grass: p < 0.001; Rocks: p = 0.006), shorter strides (Grass: p < 0.001; Rocks: p = 0.008), and smoother gait (Grass AP: p < 0.001; Rocks AP: p = 0.002; Rocks ML: p = 0.02) than YA, but they also exhibited greater reductions in gait speed and stride length than YA while transitioning to the uneven grass and rocks surfaces. Within the OA group, those with greater Aß deposition exhibited decreases in smoothness with age (Grass AP: p = 0.02; Rocks AP: p = 0.03; Grass ML: p = 0.04; Rocks ML: p = 0.03), while those with lower Aß deposition exhibited increasing smoothness with age (Grass AP: p = 0.01; Rocks AP: p = 0.02; Grass ML: p = 0.08; Rocks ML: p = 0.07). Better functional mobility was associated with less smooth gait (Grass ML: p = 0.02; Rocks ML: p = 0.05) and with less variable gait smoothness (Grass and Rocks AP: both p = 0.04) in the OA group. CONCLUSION: These results suggest that, relative to YA, OA may be adopting more cautious, compensatory gait strategies to maintain smoothness when approaching surface transitions. However, OA with greater Aß deposition may have limited ability to adopt compensatory gait strategies to increase the smoothness of their walking as they get older because of neuropathological changes altering the sensory integration process and causing worse dynamic balance (i.e., jerkier gait). Functional mobility, in addition to age and Aß deposition, may be an important factor of whether or not an OA chooses to employ compensatory strategies to prioritize smoothness while walking and what type of compensatory strategy an OA chooses.

Bacterial and Viral Diversity of Didelphid Opossums from Brazil.

Marsupials belonging to the Didelphis genus are widely distributed in the American Continent, and Didelphis albiventris and Didelphis aurita, are common in all of their areas of distribution in Brazil. Here we describe the bacterial and viral diversity of samples from opossums captured in three forest fragments in the State of São Paulo, Brazil. Microbiomes from the same body site were more similar across species and sampling sites while oral swabs presented higher bacterial diversity than rectal swabs. We also identified sequences related to bacterial species involved in zoonotic diseases. The detection of pathogens in such abundant mammal species warns for the possibility of emergence in other species.

HIV-1 Nef Changes the Proteome of T Cells Extracellular Vesicles Depleting IFITMs and Other Antiviral Factors.

Extracellular vesicles (EVs) are biomolecule carriers for intercellular communication in health and disease. Nef is a HIV virulence factor that is released from cells within EVs and is present in plasma EVs of HIV-1 infected individuals. We performed a quantitative proteomic analysis to fully characterize the Nef-induced changes in protein composition of T cell-derived EVs and identify novel host targets of HIV. Several proteins with well-described roles in infection or not previously associated with HIV pathogenesis were specifically modulated by Nef in EVs. Among the downregulated proteins are the interferon-induced transmembrane 1, 2, and 3 (IFITM1-3) proteins, broad-spectrum antiviral factors known to be cell-to-cell transferable by EVs. We demonstrate that Nef depletes IFITM1-3 from EVs by excluding these proteins from the plasma membrane and lipid rafts, which are sites of EVs biogenesis in T cells. Our data establish Nef as a modulator of EVs' global protein content and as an HIV factor that antagonizes IFITMs.

The relationship between visual function and physical performance in the Study of Muscle, Mobility and Aging (SOMMA).

PURPOSE: The relationship of types of visual function to different aspects of physical function, especially strength and coordination, has been understudied, but delineation of these relationships could suggest potentially modifiable targets prior to the onset of disability. METHODS: Cross-sectional analysis of visual function (self-reported eyesight and eye disease, visual acuity, contrast sensitivity) and physical function tests in 877 older adults (mean age 76.36±5.01 years, 59.2% women, and 13.3% Black race). Separate linear regression models were constructed for short physical performance battery (SPPB), expanded SPPB (eSPPB), their components (gait speed, chair stand, balance, narrow walk), stair climb, four-square step, leg extension peak power and strength, and grip strength. RESULTS: In adjusted models, worse acuity, worse contrast sensitivity, and self-reported poor vision were significantly associated with worse performance on the eSPPB and four-square step test. Worse contrast sensitivity, but not acuity, was significantly associated with shorter balance times, slower chair stand pace, longer stair climb time, and worse SPPB score. Associations of worse acuity and contrast sensitivity with weaker leg extension power, leg strength, and grip strength were attenuated by covariate adjustment. Self-reported macular degeneration, but not cataract or glaucoma, was associated with worse performance on SPPB, eSPPB, balance, stair climb, and four-square step tests in adjusted models. Worse contrast sensitivity and macular degeneration remained associated with worse SPPB and balance after controlling for visual acuity and self-reported eyesight. CONCLUSIONS: Poor contrast sensitivity was more strongly associated with worse physical performance than acuity, especially for complex tasks that dynamically challenge coordination and balance. Future studies should examine if older adults with contrast sensitivity impairment would benefit from targeted intervention to decrease their risk of disability.

Anti-Toxoplasma gondii activity of Trametes versicolor (Turkey tail) mushroom extract.

Toxoplasma gondii (T. gondii) infection continues to rise globally in humans and animals with high socioeconomic and public health challenges. Current medications used against T. gondii infection are limited in efficacy, safety, and affordability. This research was conducted to assess the higher fungi extract effect on T. gondii tachyzoites growth in vitro and possibly decipher its mechanism of action. Furthermore, we evaluated the extract's effect on human foreskin fibroblast viability. The methanol extracts of Turkey tail (TT) mushroom was tested against T. gondii tachyzoites growth using an RH-RFP type I strain that expresses red fluorescent protein throughout culture in a dose-dependent manner using a fluorescent plate reader. Similarly, we tested the effect of the extract on host cell viability. We observed that TT extract inhibited tachyzoites growth with a 50% minimum inhibitory concentration (IC50s), IC50 = 5.98 ± 1.22 µg/mL, and 50% cytotoxic concentration (CC50s), CC50 ≥ 100 µg/mL. It was discovered that TT extract induced strong mitochondria superoxide and  reactive oxygen species production and disrupted mitochondria membrane potential in T. gondii tachyzoites. Additionally, scanning electron microscopy depicted that TT extract and pyrimethamine (PY) caused a morphological deformation of tachyzoites in vitro. In conclusion, TT methanol extract made up of phytosterols, bioactive sphingolipids, peptides, phenolic acids, and lactones could be a promising source of new compounds for the future development of anti-Toxoplasma gondii drugs. Extracts were non-cytotoxic, even at higher concentrations.

Associations of physical function and body mass index with functional brain networks in community-dwelling older adults.

Deficits in physical function that occur with aging contribute to declines in quality of life and increased mortality. There has been a growing interest in examining associations between physical function and neurobiology. Whereas high levels of white matter disease have been found in individuals with mobility impairments in structural brain studies, much less is known about the relationship between physical function and functional brain networks. Even less is known about the association between modifiable risk factors such as body mass index (BMI) and functional brain networks. The current study examined baseline functional brain networks in 192 individuals from the Brain Networks and mobility (B-NET) study, an ongoing longitudinal, observational study in community-dwelling adults aged 70 and older. Physical function and BMI were found to be associated with sensorimotor and dorsal attention network connectivity. There was a synergistic interaction such that high physical function and low BMI were associated with the highest network integrity. White matter disease did not modify these relationships. Future work is needed to understand the causal direction of these relationships.

Corrigendum: Examining the intersection of cognitive and physical function measures: Results from the brain networks and mobility (B-NET) study.

[This corrects the article DOI: 10.3389/fnagi.2023.1090641.].

Examining the intersection of cognitive and physical function measures: Results from the brain networks and mobility (B-NET) study.

Background and objectives: Although evidence exists that measures of mobility and cognition are correlated, it is not known to what extent they overlap, especially across various domains. This study aimed to investigate the intersection of 18 different objective cognitive and physical function measures from a sample of unimpaired adults aged 70 years and older. Research design and methods: Canonical correlation analysis was utilized to explore the joint cross-sectional relationship between 13 cognitive and 6 physical function measures in the baseline visit of the Brain Networks and Mobility Function (B-NET) Study (n = 192). Results: Mean age of participants was 76.4 years. Two synthetic functions were identified. Function 1 explained 26.3% of the shared variability between the cognition and physical function variables, whereas Function 2 explained 19.5%. Function 1 termed "cognitive and physical speed" related the expanded Short Physical Performance Battery (eSPPB), 400-m walk speed, and Dual Task gait speed measures of physical function to semantic fluency animals scores, Digit Symbol Coding (DSC), and Trail Making Test B. Function 2 termed "complex motor tasks and cognitive tasks" related the Force Plate Postural Sway Foam Task and Dual Task to the following cognitive variables: MoCA Adjusted Score, Verbal Fluency L words, Craft story immediate and delayed recall, and Trail Making Test B. Discussion and implications: We identified groups of cognitive and physical functional abilities that were linked in cross-sectional analyses, which may suggest shared underlying neural network pathway(s) related to speed (Function 1) or complexity (Function 2). Translational significance: Whether such neural processes decline before measurable functional losses or may be important targets for future interventions that aim to prevent disability also remains to be determined.

Association Between Contrast Sensitivity and Physical Function in Cognitively Healthy Older Adults: The Brain Networks and Mobility Function Study.

BACKGROUND: To evaluate whether contrast sensitivity is associated with lower extremity physical function in cognitively intact older adults. METHODS: Cross-sectional analysis of the relationship of binocular and worse eye log contrast sensitivity (LCS) to expanded Short Physical Performance Battery (eSPPB) and its components (gait speed, narrow walking speed, chair stand pace, and balance) in 192 cognitively healthy older adults. The association of LCS with postural sway and gait was also tested with tasks that further challenged functional reserve. RESULTS: Mean age was 76.4 years with 56% identifying as female and over 98.5% having good corrected visual acuity. Lower LCS was significantly associated with worse performance on the eSPPB, 4-M gait speed, narrow walking speed, and balance time in unadjusted and adjusted models. The relationship between worse eye LCS and larger postural sway was 3 times greater on a foam surface (beta 1.07, 95% CI [0.35, 1.80]) than a firm surface (beta 0.35, 95% CI [0.05, 0.65]), and both were robust to adjustment for confounders; similar findings were observed with binocular LCS. Lower binocular LCS had a greater decremental effect on gait velocity during the fast pace (beta -0.58, 95% CI [-0.90, -0.27]) than the usual pace (Beta -0.39 [-0.63, -0.15]) gait task. CONCLUSIONS: These findings suggest that cognitively unimpaired older adults without significant visual acuity impairment can have subtle preclinical deficits in contrast sensitivity and physical function that could place them at risk of mobility and balance issues. Future studies should determine whether this subset of older adults may benefit from targeted intervention to prevent disability.

Relationship of Self-reported and Performance-based Visual Function With Performance-based Measures of Physical Function: The Health ABC Study.

BACKGROUND: To assess the relationship between self-reported and performance-based visual impairment (VI) and lower extremity physical function. METHODS: Cross-sectional analysis of 2 219 Health ABC participants who completed vision testing and the Short Physical Performance Battery (SPPB). Linear regression models used either self-reported (weighted visual function question [VFQ] score) or performance-based (visual acuity [VA], log contrast sensitivity [LCS], Frisby stereoacuity [SA]) to predict SPPB or its components-gait speed, chair stands, or standing balance-with and without covariate adjustment. RESULTS: Mean age was 73.5 years (range 69-80); 52.4% were female and 37.4% African American. All VI measures were strongly associated with SPPB in unadjusted and adjusted models (p < .001). A self-reported VFQ score 1 standard deviation lower than the mean (mean 87.8 out of 100) demonstrated a -0.241 (95% confidence interval [CI]: -0.325, -0.156) adjusted difference in SPPB. After controlling for covariates, VA of <20/40 (41%) demonstrated a -0.496 (-0.660, -0.331) lower SPPB score while SA score>85 arcsec (30%) had a -0.449 (-0.627, -0.271) adjusted SPPB score versus those with better visual function. LCS < 1.55 (28.6%) was associated with a -0.759 (-0.938, -0.579) lower and LCS ≤ 1.30 (8%) with a -1.216 (-1.515, -0.918) lower adjusted SPPB score relative to better LCS. In a final multivariable model containing multiple vision measures, LCS remained independently associated with SPPB and all components, while SA remained associated with balance (all p < .05). CONCLUSIONS: Both self-reported and performance-based VI are strongly associated with poor lower extremity physical function. These findings may identify a subgroup of older adults with co-existing visual and physical dysfunction who may benefit from targeted screening and intervention to prevent disability.

Importance of primary care for underserved cancer patients with multiple chronic conditions.

PURPOSE: To understand the impact of pre-existing conditions on healthcare utilization among under- and uninsured patients in the transition from cancer treatment to post-treatment survivorship. METHODS: Using electronic health record data, we constructed a cohort of patients seen in an integrated county health system between 1/1/2010 and 12/31/2016. Six hundred thirty-one adult patients diagnosed with non-metastatic breast or colorectal cancer during this period (cases) were matched 1:1 on sex and Charlson comorbidity index to non-cancer patients who had at least two chronic conditions and with at least one visit to the health system during the study period (controls). Conditional fixed effects Poisson regression models compared number of primary care and emergency department (ED) visits and completed [vs. no show or missed] appointments between cancer and non-cancer patients. RESULTS: Cancer patients had significantly lower number of visits compared with non-cancer patients (N = 46,965 vs. 85,038). Cancer patients were less likely to have primary care (IRR = 0.25; 95% CI: 0.24, 0.27) and ED visits (IRR = 0.57; 95% CI: 0.50, 0.64) but more likely to complete a scheduled appointment (AOR = 4.83; 95% CI: 4.32, 5.39) compared with non-cancer patients. Cancer patients seen in primary care at a higher rate were more likely to visit the ED (IRR = 2.06; 95% CI: 1.52, 2.80) than those seen in primary care at a lower rate. CONCLUSION: Health systems need to find innovative, effective solutions to increase primary care utilization among cancer patients with chronic care conditions to ensure optimal management of both chronic conditions and cancer. IMPLICATIONS FOR CANCER SURVIVORS: Maintaining regular connections with primary care providers during active cancer treatment should be promoted.

Effect of the STRIDE fall injury prevention intervention on falls, fall injuries, and health-related quality of life.

BACKGROUND: Falls are common in older adults and can lead to severe injuries. The Strategies to Reduce Injuries and Develop Confidence in Elders (STRIDE) trial cluster-randomized 86 primary care practices across 10 health systems to a multifactorial intervention to prevent fall injuries, delivered by registered nurses trained as falls care managers, or enhanced usual care. STRIDE enrolled 5451 community-dwelling older adults age ≥70 at increased fall injury risk. METHODS: We assessed fall-related outcomes via telephone interviews of participants (or proxies) every 4 months. At baseline, 12 and 24 months, we assessed health-related quality of life (HRQOL) using the EQ-5D-5L and EQ-VAS. We used Poisson models to assess intervention effects on falls, fall-related fractures, fall injuries leading to hospital admission, and fall injuries leading to medical attention. We used hierarchical longitudinal linear models to assess HRQOL. RESULTS: For recurrent event models, intervention versus control incidence rate ratios were 0.97 (95% confidence interval [CI], 0.93-1.00; p = 0.048) for falls, 0.93 (95% CI, 0.80-1.08; p = 0.337) for self-reported fractures, 0.89 (95% CI, 0.73-1.07; p = 0.205) for adjudicated fractures, 0.91 (95% CI, 0.77-1.07; p = 0.263) for falls leading to hospital admission, and 0.97 (95% CI, 0.89-1.06; p = 0.477) for falls leading to medical attention. Similar effect sizes (non-significant) were obtained for dichotomous outcomes (e.g., participants with ≥1 events). The difference in least square mean change over time in EQ-5D-5L (intervention minus control) was 0.009 (95% CI, -0.002 to 0.019; p = 0.106) at 12 months and 0.005 (95% CI, -0.006 to 0.015; p = 0.384) at 24 months. CONCLUSIONS: Across a standard set of outcomes typically reported in fall prevention studies, we observed modest improvements, one of which was statistically significant. Future work should focus on patient-, practice-, and organization-level operational strategies to increase the real-world effectiveness of interventions, and improving the ability to detect small but potentially meaningful clinical effects. CLINICALTRIALS: gov identifier: NCT02475850.

A Randomized Preference Trial Comparing Cognitive-Behavioral Therapy and Yoga for the Treatment of Late-Life Worry: Examination of Impact on Depression, Generalized Anxiety, Fatigue, Pain, Social Participation, and Physical Function.

Background: Depression, generalized anxiety, fatigue, diminished physical function, reduced social participation, and pain are common for many older adults and negatively impact quality of life. The purpose of the overall trial was to compare the effects of cognitive-behavioral therapy (CBT) and yoga on late-life worry, anxiety, and sleep; and examine preference and selection effects on these outcomes. Objective: The present analyses compared effects of the 2 interventions on additional outcomes (depressive symptoms, generalized anxiety symptoms, fatigue, pain interference/intensity, physical function, social participation); and examined whether there are preference and selection effects for these treatments. Methods: A randomized preference trial of CBT and yoga was conducted in adults ≥60 years who scored ≥26 on the Penn State Worry Questionnaire-Abbreviated (PSWQ-A), recruited from outpatient medical clinics, mailings, and advertisements. Cognitive-behavioral therapy consisted of 10 weekly telephone sessions. Yoga consisted of 20 bi-weekly group yoga classes. Participants were randomized to(1): a randomized controlled trial (RCT) of CBT or yoga (n = 250); or (2) a preference trial in which they selected their treatment (CBT or yoga; n = 250). Outcomes were measured at baseline and post-intervention. Results: Within the RCT, there were significant between-group differences for both pain interference and intensity. The pain interference score improved more for the CBT group compared with the yoga group [intervention effect of (mean (95% CI) = 2.5 (.5, 4.6), P = .02]. For the pain intensity score, the intervention effect also favored CBT over yoga [.7 (.2, 1.3), P < .01]. Depressive symptoms, generalized anxiety, and fatigue showed clinically meaningful within-group changes in both groups. There were no changes in or difference between physical function or social participation for either group. No preference or selection effects were found. Conclusion: Both CBT and yoga may be useful for older adults for improving psychological symptoms and fatigue. Cognitive-behavioral therapy may offer even greater benefit than yoga for decreasing pain.

Gradient and Acceleration of Decline in Physical and Cognitive Functions in Older Adults: A Disparity Analysis.

BACKGROUND: Substantive previous work has shown that both gait speed and global cognition decline as people age. Rates of their decline, as opposed to cross-sectional measurements, could be more informative of future functional status and other clinical outcomes because they more accurately represent deteriorating systems. Additionally, understanding the sex and racial disparity in the speed of deterioration, if any, is also important as ethnic minorities are at an increased risk of mobility disability and dementia. METHOD: Data from 2 large longitudinal intervention studies were integrated. Rates of decline were derived from individual-level measures of gait speed of 400-m walk and scores on the Modified Mini Mental State Examination (3MSE). We also assessed age-associated declines and accelerations in changes across the ages represented in the studies (age range 53-90). RESULTS: The mean rate of decline in 400-m gait speed across individuals was 0.03 m/s per year, and multivariable analysis showed a significant acceleration in decline of -0.0013 m/s/y2 (p < .001). Both race and sex moderated the rate of decline. For global cognition, the mean rate of decline was 0.05 of a point per year on the 3MSE scale, and acceleration in the rate of decline was significant (-0.017 point/y2, p < .001), but neither sex nor race moderated the decline. CONCLUSION: Rate of decline in physical but not cognitive function appears moderated by sex and race. This finding, as well as rates and accelerations of decline estimated herein, could inform future intervention studies. CLINICAL TRIALS REGISTRATION NUMBER: NCT00017953 (Look AHEAD); NCT01410097 (Look AHEAD ancillary); NCT00116194 (LIFE).

Long-Term Effects of Cognitive-Behavioral Therapy and Yoga for Worried Older Adults.

OBJECTIVES: Cognitive-behavioral therapy (CBT) and yoga decrease worry and anxiety. There are no long-term data comparing CBT and yoga for worry, anxiety, and sleep in older adults. The impact of preference and selection on these outcomes is unknown. In this secondary data analysis, we compared long-term effects of CBT by telephone and yoga on worry, anxiety, sleep, depressive symptoms, fatigue, physical function, social participation, and pain; and examined preference and selection effects. DESIGN: In this randomized preference trial, participants (N = 500) were randomized to a: 1) randomized controlled trial (RCT) of CBT or yoga (n = 250); or 2) preference trial (selected CBT or yoga; n = 250). Outcomes were measured at baseline and Week 37. SETTING: Community. PARTICIPANTS: Community-dwelling older adults (age 60+ years). INTERVENTIONS: CBT (by telephone) and yoga (in-person group classes). MEASUREMENTS: Penn State Worry Questionnaire - Abbreviated (worry);1,2 Insomnia Severity Index (sleep);3 PROMIS Anxiety Short Form v1.0 (anxiety);4,5 Generalized Anxiety Disorder Screener (generalized anxiety);6,7 and PROMIS-29 (depression, fatigue, physical function, social participation, pain).8,9 RESULTS: Six months after intervention completion, CBT and yoga RCT participants reported sustained improvements from baseline in worry, anxiety, sleep, depressive symptoms, fatigue, and social participation (no significant between-group differences). Using data combined from the randomized and preference trials, there were no significant preference or selection effects. Long-term intervention effects were observed at clinically meaningful levels for most of the study outcomes. CONCLUSIONS: CBT and yoga both demonstrated maintained improvements from baseline on multiple outcomes six months after intervention completion in a large sample of older adults. TRIAL REGISTRATION: www. CLINICALTRIALS: gov Identifier NCT02968238.

Predicting Future Mobility Limitation in Older Adults: A Machine Learning Analysis of Health ABC Study Data.

BACKGROUND: Mobility limitation in older adults is common and associated with poor health outcomes and loss of independence. Identification of at-risk individuals remains challenging because of time-consuming clinical assessments and limitations of statistical models for dynamic outcomes over time. Therefore, we aimed to develop machine learning models for predicting future mobility limitation in older adults using repeated measures data. METHODS: We used annual assessments over 9 years of follow-up from the Health, Aging, and Body Composition study to model mobility limitation, defined as self-report of any difficulty walking a quarter mile or climbing 10 steps. We considered 46 predictors, including demographics, lifestyle, chronic conditions, and physical function. With a split sample approach, we developed mixed models (generalized linear and Binary Mixed Model forest) using (a) all 46 predictors, (b) a variable selection algorithm, and (c) the top 5 most important predictors. Age was included in all models. Performance was evaluated using area under the receiver operating curve in 2 internal validation data sets. RESULTS: Area under the receiver operating curve ranged from 0.80 to 0.84 for the models. The most important predictors of mobility limitation were ease of getting up from a chair, gait speed, self-reported health status, body mass index, and depression. CONCLUSIONS: Machine learning models using repeated measures had good performance for identifying older adults at risk of developing mobility limitation. Future studies should evaluate the utility and efficiency of the prediction models as a tool in clinical settings for identifying at-risk older adults who may benefit from interventions aimed to prevent or delay mobility limitation.

Is Wrist Accelerometry Suitable for Threshold Scoring? A Comparison of Hip-Worn and Wrist-Worn ActiGraph Data in Low-Active Older Adults With Obesity.

BACKGROUND: Hip- and wrist-worn ActiGraph accelerometers are widely used in research on physical activity as they offer an objective assessment of movement intensity across the day. Herein we characterize and contrast key structured physical activities and common activities of daily living via accelerometry data collected at the hip and wrist from a sample of community-dwelling older adults. METHODS: Low-active, older adults with obesity (age 60+ years) were fit with an ActiGraph GT3X+ accelerometer on their nondominant wrist and hip before completing a series of tasks in a randomized order, including sitting/standing, sweeping, folding laundry, stair climbing, ambulation at different intensities, and cycling at different intensities. Participants returned a week later and completed the tasks once again. Vector magnitude counts/second were time-matched during each task and then summarized into counts/minute (CPM). RESULTS: Monitors at both wear locations similarly characterized standing, sitting, and ambulatory tasks. A key finding was that light home chores (sweeping, folding laundry) produced higher and more variable CPM values than fast walking via wrist ActiGraph. Regression analyses revealed wrist CPM values were poor predictors of hip CPM values, with devices aligning best during fast walking (R2 = 0.25) and stair climbing (R2 = 0.35). CONCLUSIONS: As older adults spend a considerable portion of their day in nonexercise activities of daily living, researchers should be cautious in the use of simply acceleration thresholds for scoring wrist-worn accelerometer data. Methods for better classifying wrist-worn activity monitor data in older adults are needed.

Predictors of preference for cognitive-behavioral therapy (CBT) and yoga interventions among older adults.

The purpose of this study was to examine factors that influence a person's choice of cognitive-behavioral therapy (CBT) or yoga, the stability of these preferences, and the impact of preference on engagement and process measures. We conducted a randomized preference trial of CBT and yoga in 500 adults ≥60 years with symptoms of worry. Participants reported their intervention preference, strength of preference, and factors impacting preference. Engagement in the intervention (session completion and dropout rates) was assessed. Process measures included satisfaction with the intervention, therapeutic alliance, and intervention expectancy. Neither intervention preference (48% and 52% chose CBT and yoga, respectively) nor strength of preference differed significantly between the two preference trial groups. Intervention expectancies at baseline among those in the preference trial were approximately 4.5 units (40-point scale) higher for their preferred intervention (p < .0001 within each group). A principal component analysis of factors influencing preference identified three constructs. Using logistic regression, components focused on attitudes about CBT or yoga were predictive of ultimate preference (odds ratio = 11.5, 95% C.I.6.3-21.0 per 1SD difference in component 1 for choosing CBT; odds ratio = 7.8, 95% CI4.3-13.9 per 1SD difference in component 2 for choosing yoga). There were no significant differences between the randomized and preference trials on intervention adherence, completion of assessments, intervention satisfaction, or working alliance. Receiving a preferred treatment had no significant effects on intervention outcomes through participant engagement or process measures. When options are limited, providers may have confidence in offering the most readily available non-pharmacological treatments.

A case study of ascertainment bias for the primary outcome in the Strategies to Reduce Injuries and Develop Confidence in Elders (STRIDE) trial.

BACKGROUND/AIM: In clinical trials, there is potential for bias from unblinded observers that may influence ascertainment of outcomes. This issue arose in the Strategies to Reduce Injuries and Develop Confidence in Elders trial, a cluster randomized trial to test a multicomponent intervention versus enhanced usual care (control) to prevent serious fall injuries, originally defined as a fall injury leading to medical attention. An unblinded nurse falls care manager administered the intervention, while the usual care arm did not involve contact with a falls care manager. Thus, there was an opportunity for falls care managers to refer participants reporting falls to seek medical attention. Since this type of observer bias could not occur in the usual care arm, there was potential for additional falls to be reported in the intervention arm, leading to dilution of the intervention effect and a reduction in study power. We describe the clinical basis for ascertainment bias, the statistical approach used to assess it, and its effect on study power. METHODS: The prespecified interim monitoring plan included a decision algorithm for assessing ascertainment bias and adapting (revising) the primary outcome definition, if necessary. The original definition categorized serious fall injuries requiring medical attention into Type 1 (fracture other than thoracic/lumbar vertebral, joint dislocation, cut requiring closure) and Type 2 (head injury, sprain or strain, bruising or swelling, other). The revised definition, proposed by the monitoring plan, excluded Type 2 injuries that did not necessarily require an overnight hospitalization since these would be most subject to bias. These injuries were categorized into those with (Type 2b) and without (Type 2c) medical attention. The remaining Type 2a injuries required medical attention and an overnight hospitalization. We used the ratio of 2b/(2b + 2c) in intervention versus control as a measure of ascertainment bias; ratios > 1 indicated the likelihood of falls care manager bias. We determined the effect of ascertainment bias on study power for the revised (Types 1 and 2a) versus original definition (Types 1, 2a, and 2b). RESULTS: The estimate of ascertainment bias was 1.14 (95% confidence interval: 0.98, 1.30), providing evidence of the likelihood of falls care manager bias. We estimated that this bias diluted the hazard ratio from the hypothesized 0.80 to 0.86 and reduced power to under 80% for the original primary outcome definition. In contrast, adapting the revised definition maintained study power at nearly 90%. CONCLUSION: There was evidence of ascertainment bias in the Strategies to Reduce Injuries and Develop Confidence in Elders trial. The decision to adapt the primary outcome definition reduced the likelihood of this bias while preserving the intervention effect and study power.