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Background: Statins are lipid-lowering agents with anti-inflammatory effects. Data surrounding the benefits of statins in patients with coronavirus disease 2019 (COVID-19) are conflicting. We sought to better understand the impact of statins in the context of COVID-19-related inflammation., Methods: We leveraged the International Study of Inflammation in COVID-19, a prospective multicenter cohort of patients hospitalized for COVID-19 between February 2020 and October 2022. Participants underwent systematic assessment of biomarkers of inflammation. We used logistic regression modeling and inverse probability-of-treatment weighting (IPTW) to examine the association between prior statin use and the composite outcome of in-hospital death, need for mechanical ventilation, and need for renal replacement therapy., Results: A total of 4464 patients were included in the study, of whom 1364 (27.5%) were taking a statin prior to admission. There were 1061 primary outcome events, including 540 deaths, 854 mechanical ventilation and 313 renal replacement therapy. Amongst biomarkers of inflammation, statin use was associated solely with lower levels of soluble urokinase plasminogen activator receptor (suPAR) after adjusting for known confounders. In multivariable logistic regression analysis, statin use was associated with lower odds of the composite outcome (adjusted odds ratio (aOR) 0.63, 95% CI [0.53-0.76]) compared to patients not on statins. Findings were consistent with IPTW (aOR 0.92, 95% CI [0.89- 0.95]). The proportion of the effect of statin on the primary outcome mediated by suPAR was estimated at 31.5%., Conclusion: Prior-statin use is associated with improved outcomes and lower inflammation as measured by suPAR levels in patients hospitalized for COVID-19., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Introduction: It is unclear whether moderate-to-vigorous physical activity (MVPA) is associated with a lower mortality risk, over and above its contribution to total physical activity volume., Methods: 46,682 adults (mean age: 64 years) were included in a meta-analysis of nine prospective cohort studies. Each cohort generated tertiles of accelerometry-measured physical activity volume and volume-adjusted MVPA. Hazard ratios (HR, with 95% confidence intervals) for mortality were estimated separately and in joint models combining volume and MVPA. Data was collected between 2001 and 2019 and analyzed in 2023., Results: During a mean follow-up of 9 years, 4,666 deaths were recorded. Higher physical activity volume, and a greater contribution from volume-adjusted MVPA, were each associated with lower mortality hazard in multivariable-adjusted models. Compared to the least active tertile, higher physical activity volume was associated with a lower mortality (HRs: 0.62; 0.58, 0.67 and 0.50; 0.42, 0.60 for ascending tertiles). Similarly, a greater contribution from MVPA was associated with a lower mortality (HRs: 0.94; 0.85, 1.04 and 0.88; 0.79, 0.98). In joint analysis, a lower mortality from higher volume-adjusted MVPA was only observed for the middle tertile of physical activity volume., Conclusions: The total volume of physical activity was associated with a lower risk of mortality to a greater extent than the contribution of MVPA to physical activity volume. Integrating any intensity of physical activity into daily life may lower mortality risk in middle-aged and older adults, with a small added benefit if the same amount of activity is performed with a higher intensity., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

The National Heart, Lung, and Blood Institute convened a virtual workshop in September 2022 to discuss "Optimal Instruments for Measurement of Diet, Physical Activity, and Sleep." This report summarizes the proceedings, identifying current research gaps and future directions for measuring different lifestyle behaviors in adult population-based studies. Key discussions centered on integrating report-based methods, like questionnaires, with device-based assessments, including wearables and physiological measures such as biomarkers and omics to enhance self-reported metrics and better understand the underlying biologic mechanisms of chronic diseases. Emphasis was placed on the need for data harmonization, including the adoption of standard terminology, reproducible metrics, and accessible raw data, to enhance the analysis through artificial intelligence and machine learning techniques. The workshop highlighted the importance of standardizing procedures for integrated behavioral phenotypes using time-series data. These efforts aim to refine data accuracy and comparability across studies and populations, thereby advancing our understanding of lifestyle behaviors and their impact on chronic disease outcomes over the life course.

This paper introduces functional quantile principal component analysis (FQPCA), a dimensionality reduction technique that extends the concept of functional principal components analysis (FPCA) to the examination of participant-specific quantiles curves. Our approach borrows strength across participants to estimate patterns in quantiles, and uses participant-level data to estimate loadings on those patterns. As a result, FQPCA is able to capture shifts in the scale and distribution of data that affect participant-level quantile curves, and is also a robust methodology suitable for dealing with outliers, heteroscedastic data or skewed data. The need for such methodology is exemplified by physical activity data collected using wearable devices. Participants often differ in the timing and intensity of physical activity behaviors, and capturing information beyond the participant-level expected value curves produced by FPCA is necessary for a robust quantification of diurnal patterns of activity. We illustrate our methods using accelerometer data from the National Health and Nutrition Examination Survey, and produce participant-level 10%, 50%, and 90% quantile curves over 24 h of activity. The proposed methodology is supported by simulation results, and is available as an R package., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. [br]For permissions, please e-mail: journals.permissions@oup.com.)

Background: Provoked anger is associated with an increased risk of cardiovascular disease events. The underlying mechanism linking provoked anger as well as other core negative emotions including anxiety and sadness to cardiovascular disease remain unknown. The study objective was to examine the acute effects of provoked anger, and secondarily, anxiety and sadness on endothelial cell health., Methods and Results: Apparently healthy adult participants (n=280) were randomized to an 8-minute anger recall task, a depressed mood recall task, an anxiety recall task, or an emotionally neutral condition. Pre-/post-assessments of endothelial health including endothelium-dependent vasodilation (reactive hyperemia index), circulating endothelial cell-derived microparticles (CD62E+, CD31+/CD42-, and CD31+/Annexin V+) and circulating bone marrow-derived endothelial progenitor cells (CD34+/CD133+/kinase insert domain receptor+ endothelial progenitor cells and CD34+/kinase insert domain receptor+ endothelial progenitor cells) were measured. There was a group×time interaction for the anger versus neutral condition on the change in reactive hyperemia index score from baseline to 40 minutes ( P =0.007) with a mean±SD change in reactive hyperemia index score of 0.20±0.67 and 0.50±0.60 in the anger and neutral conditions, respectively. For the change in reactive hyperemia index score, the anxiety versus neutral condition group by time interaction approached but did not reach statistical significance ( P =0.054), and the sadness versus neutral condition group by time interaction was not statistically significant ( P =0.160). There were no consistent statistically significant group×time interactions for the anger, anxiety, and sadness versus neutral condition on endothelial cell-derived microparticles and endothelial progenitor cells from baseline to 40 minutes., Conclusions: In this randomized controlled experimental study, a brief provocation of anger adversely affected endothelial cell health by impairing endothelium-dependent vasodilation.

Accelerometers have been used to objectively quantify physical activity, but they can pose a high burden. This study was conducted to determine the feasibility of using a single-item smartphone-based ecological momentary assessment (EMA) in lieu of accelerometers in long-term assessment of daily exercise. Data were collected from a randomized controlled trial of intermittently exercising, otherwise healthy adults (N = 79; 57% female, mean age: 31.9 ± 9.5 years) over 365 days. Smartphone-based EMA self-reports of exercise entailed daily end-of-day responses about physical activity; the participants also wore a Fitbit device to measure physical activity. The Kappa statistic was used to quantify the agreement between accelerometer-determined (24 min of moderate-to-vigorous physical activity [MVPA] within 30 min) and self-reported exercise. Possible demographic predictors of agreement were assessed. Participants provided an average of 164 ± 87 days of complete data. The average within-person Kappa was κ = 0.30 ± 0.22 (range: -0.15-0.73). Mean Kappa ranged from 0.16 to 0.30 when the accelerometer-based definition of an exercise bout varied in duration from 15 to 30 min of MVPA within any 30 min period. Among the correlates examined, sex was significantly associated with agreement; mean agreement was higher among women ( κ = 0.37) than men ( κ = 0.20). Agreement between EMA self-reported and accelerometer-measured exercise was fair, suggesting that long-term exercise monitoring through a single-item EMA may be acceptable.

Purpose: The purpose of this study was to examine whether engagement in health behaviors changed from pre-pandemic (2019) to during the pandemic (2020)., Methods: The combined 2019-2020 National Survey of Children's Health (NSCH) was used to inform this study. The NSCH is an annual survey designed to provide national estimates of key indicators of childhood health and well-being. Physical activity (number of days/week with >60 min of activity), screen-time (hours/day of TV viewing and computer use), and sleep (hours/day) were assessed by parental report. Adjusted binomial and multinomial logistic regression models were used to determine the association between survey year and health behaviors., Results: Children and adolescents were 36% more likely to be physically inactive in 2020 compared to 2019. Additionally, children and adolescents were 14% more likely to meet sleep guidelines and 39% less likely to meet screen-time guidelines in 2020 compared to 2019, independent of age, sex, race/ethnicity, and poverty level. Children (6-13 year) and adolescents (14-17 years) were 10% and 15% less likely to get below the recommended amount of sleep in 2020 compared to 2019, respectively., Conclusion: Prevalence of meeting sleep guidelines increased among children and adolescents in 2020 but decreased for physical activity and screen-time. Initiatives targeting activity and screen-time may be urgently needed. Whether rates of these health behaviors return to pre-pandemic levels over the next few years should be closely assessed., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Evidence guiding the pre-hematopoietic stem cell transplantation (HSCT) cardiovascular evaluation is limited. We sought to derive and validate a pre-HSCT score for the cardiovascular risk stratification of HSCT candidates., Methods and Results: We leveraged the CARE-BMT (Cardiovascular Registry in Bone Marrow Transplantation) study, a contemporary multicenter observational study of adult patients who underwent autologous or allogeneic HSCT between 2008 and 2019 (N=2435; mean age at transplant of 55 years; 4.9% Black). We identified the subset of variables most predictive of post-HSCT cardiovascular events, defined as a composite of cardiovascular death, myocardial infarction, heart failure, stroke, atrial fibrillation or flutter, and sustained ventricular tachycardia. We then developed a point-based risk score using the hazard ratios obtained from Cox proportional hazards modeling. The score was externally validated in a separate cohort of 919 HSCT recipients (mean age at transplant 54 years; 20.4% Black). The risk score included age, transplant type, race, coronary artery disease, heart failure, peripheral artery disease, creatinine, triglycerides, and prior anthracycline dose. Risk scores were grouped as low-, intermediate-, and high-risk, with the 5-year cumulative incidence of cardiovascular events being 4.0%, 10.3%, and 22.4%, respectively. The area under the receiver operating curves for predicting cardiovascular events at 100 days, 5 and 10 years post-HSCT were 0.65 (95% CI, 0.59-0.70), 0.73 (95% CI, 0.69-0.76), and 0.76 (95% CI, 0.69-0.81), respectively. The model performed equally well in autologous and allogeneic recipients, as well as in the validation cohort., Conclusions: The CARE-BMT risk score is easy to calculate and could help guide referrals of high-risk HSCT recipients to cardiovascular specialists before transplant and guide long-term monitoring.

Background: Rest-activity rhythms (RARs), a measure of circadian rhythmicity in the free-living setting, are related to mortality risk, but evidence is limited on associations with cardiovascular disease (CVD) and its risk factors., Methods and Results: Participants included 4521 adults from the 2013 to 2014 National Health and Nutrition Examination Survey physical activity monitoring examination. Wrist-worn ActiGraph GT3X+ data were used to estimate RARs. Multivariable logistic models evaluated associations of RARs with prevalent CVD, hypertension, obesity, and central adiposity. Participants (mean age, 49 years) in the highest versus lowest tertile of relative amplitude (greater circadian rhythmicity) had 39% to 62% lower odds of prevalent CVD, hypertension, obesity, and central adiposity. A more active wake period was associated with 19% to 72% lower CVD, hypertension, obesity, and central adiposity odds. Higher interdaily stability (regular sleep-wake and rest-activity patterns) was related to 52% and 23% lower CVD and obesity odds, respectively. In contrast, participants in the highest versus lowest tertile of intradaily variability (fragmented RAR and inefficient sleep) had >3-fold and 24% higher CVD and obesity odds, respectively. A later and less restful sleep period was associated with 36% to 2-fold higher CVD, hypertension, obesity, and central adiposity odds. A statistically significant linear trend was observed for all associations ( P -trend<0.05)., Conclusions: A robust, stable, and less fragmented RAR, an active wake period, and an earlier and more restful sleep period are associated with lower prevalent CVD, hypertension, obesity, and central adiposity, with evidence of a dose-response relationship. The magnitude, timing, and regularity of sleep-wake and rest-activity patterns may be important targets for reducing cardiovascular risk.

Objective: Posttraumatic stress symptoms (PSS) due to acute cardiac events are common and may lead patients to avoid secondary prevention behaviors. However, patients' daily experience of cardiac event-induced PSS has not been studied after a potentially traumatic cardiac hospitalization., Method: In an observational cohort study, 108 mostly male patients with coronary heart disease were recruited after evaluation for suspected acute coronary syndrome (ACS). One month later, PSS were assessed via telephone-administered PTSD Checklist for DSM-5 (PCL-5). The exposure of interest was elevated (PCL-5 ≥ 20) vs. non-elevated PSS (PCL-5 ≤ 5). The occurrence and severity of cardiac-related intrusive thoughts were assessed 5 times daily for 2 weeks via electronic surveys on a wrist-worn device., Results: Moderate-to-severe intrusive thoughts were experienced by 48.1% of patients but more commonly by elevated-PSS (n = 36; 66.7%) than non-elevated-PSS (n = 72; 38.9%) patients. After adjustment for demographic and clinical characteristics, elevated- vs. non-elevated-PSS patients had a 9-fold higher odds of experiencing a moderate-to-severe intrusive thought during each 2-h assessment interval (adjusted OR = 9.14, 95% CI [2.99, 27.92], p < .01). After adjustment, intrusive thoughts on a 0-to-6 point scale were over two times as intense for elevated-PSS vs. non-elevated-PSS patients., Conclusions: Intrusive thoughts about cardiac risk were common in patients recently evaluated for ACS, but much more prevalent and intense in those with elevated vs non-elevated PSS., Competing Interests: Declaration of competing interest The authors declare no financial or other conflicts of interest., (Copyright © 2023. Published by Elsevier Inc.)

Purpose: Existing sedentary behavior interventions have largely achieved mixed results. Conventionally, interventions have attempted to reduce sedentary behavior using a full-day approach. An alternative strategy may be to target specific periods during the day and/or week. This study examined the day-of-the-week (Monday to Sunday) and time-of-the-day patterns (3-and 6-h periods) of sedentary behavior among U.S. Hispanics/Latinos adults., Methods: Participants ( n = 12,241) from the Hispanic Community Health Study/Study of Latinos, a multisite community-based prospective cohort study of Hispanic/Latino adults, were studied. Sedentary behavior was assessed for 1 wk using a hip-mounted accelerometer through total sedentary time, sedentary time in bouts ≥60 min, and total number of sedentary breaks. The temporal patterns of sedentary behavior metrics were evaluated using linear mixed effect models accounting for the Hispanic Community Health Study/Study of Latinos complex survey design., Results: There were statistically significant variations in temporal patterns across day-of-the-week and time-of-the-day periods for all three metrics ( P < 0.001). Adults were more sedentary on weekends than on weekdays and most sedentary on Sundays. The time-of-the-day patterns had a U-curve pattern wherein adults were most sedentary late at night, became less sedentary throughout the day, reached peak activeness around noon, then gradually became more sedentary into the evening. These patterns were largely robust across seasonality and most sociodemographic characteristics, including age, employment status, work shift schedule, acculturation, and field center., Conclusions: Our findings suggest that early mornings, evenings, and weekends were the more sedentary periods in this cohort of Hispanic/Latino adults, characterized by higher volumes of sedentary time, higher volumes of time in prolonged sedentary bouts, and fewer number of sedentary breaks than other time periods, highlighting important windows of opportunity to reduce sedentary behavior., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American College of Sports Medicine.)

Background: Growing evidence has implicated sedentary behavior is associated with cardiovascular and all-cause mortality, independent of moderate to vigorous physical activity (MVPA). Contrary to national physical activity guidelines, reductions in sedentary behavior are not promoted as a lifestyle modification in hypertensive adults. This may be in part because of a paucity of evidence demonstrating that sedentary behavior confers morbidity and mortality risk in hypertensive adults., Purpose: To examine the association between device-measured sedentary behavior and risk of cardiovascular and all-cause mortality and in hypertensive adults., Methods: Data for this analysis come from the 2003 to 2006 National Health and Nutrition Examination Survey, a nationally representative survey of US adults. Sedentary behavior and MVPA were assessed with an ActiGraph 7164 accelerometer. Hypertension was classified as blood pressure at least 140/≥90 mmHg or antihypertensive medication use., Results: Median follow-up was 14.5 years. After adjusting for covariates and MVPA, greater time spent in sedentary behavior was associated with an increased risk of cardiovascular mortality [quartile 1: REF, quartile 2: hazard ratio = 1.41 [95% confidence interval (95% CI) 0.83-2.38], quartile 3: hazard ratio = 1.25 (95% CI 0.81-1.94), quartile 4: hazard ratio = 2.14 (95% CI 1.41-3.24); P trend <0.001]. Greater sedentary behavior was also associated with an increased risk of all-cause mortality [quartile 1: REF: quartile 2: hazard ratio = 1.13 (95% CI 0.83-1.52), quartile 3: hazard ratio = 1.33 (95% CI 1.00-1.78), quartile 4: hazard ratio = 2.06 (95% CI 1.60, 2.64); P trend <0.001]., Conclusion: Greater sedentary behavior is associated with increased risk of cardiovascular mortality and all-cause mortality among US adults with hypertension. These findings suggest reductions in sedentary behavior should be considered to reduce mortality risk in hypertensive adults., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Background There is limited evidence on the potential negative metabolic health impacts of prolonged and uninterrupted sedentary bouts in structurally disadvantaged youth. This study investigated associations between sedentary bout variables and metabolic health markers in the Hispanic Community Health Study/SOL Youth (Study of Latino Youth). Methods and Results SOL Youth was a population-based cohort of 1466 youth (age range, 8-16 years; 48.5% female); 957 youth were included in the analytic sample based on complete data. Accelerometers measured moderate-to-vigorous physical activity (MVPA), total sedentary time, and sedentary bout patterns (daily time spent in sedentary bouts ≥30 minutes, median sedentary bout duration, and number of daily breaks from sedentary time). Clinical measures included body mass index, waist circumference, fasting glucose, glycated hemoglobin, fasting insulin, and the homeostasis model assessment of insulin resistance. After adjusting for sociodemographics, total sedentary time, and MVPA, longer median bout durations and fewer sedentary breaks were associated with a greater body mass index percentile (b bouts =0.09 and b breaks =-0.18), waist circumference (b bouts =0.12 and b breaks =-0.20), and fasting insulin (b bouts =0.09 and b breaks =-0.21). Fewer breaks were also associated with a greater homeostasis model assessment of insulin resistance (b=-0.21). More time in bouts lasting ≥30 minutes was associated with a greater fasting glucose (b=0.18) and glycated hemoglobin (b=0.19). Conclusions Greater accumulation of sedentary time in prolonged and uninterrupted bouts had adverse associations with adiposity and glycemic control over and above total sedentary time and MVPA. Findings suggest interventions in Hispanic/Latino youth targeting both ends of the activity spectrum (more MVPA and less prolonged/uninterrupted sedentary patterns) may provide greater health benefits than those targeting only MVPA.

Objective: We evaluated the prospective association of midlife leisure-time physical activity (LTPA) and sedentary behavior (SB), and their temporal patterns, with MRI-measured carotid atherosclerotic morphology., Methods: Participants enrolled in the Carotid MRI substudy (2004-2006) of the Atherosclerosis Risk in Communities (ARIC) Study and with self-reported assessments of LTPA and SB at visits 1 (1987-1989) and 3 (1993-1995) were included in this study. LTPA was ascertained using the ARIC/Baecke physical activity questionnaire and categorized according to the American Heart Association's metric of poor, intermediate, or ideal physical activity. SB, measured as TV viewing frequency, was categorized as high, medium, and low. We used multivariable adjusted linear and logistic regression models to examine the associations between midlife (visit 3 only) and persistent (visit 1 to 3) LTPA and TV viewing with carotid artery plaque burden and components., Results: Among the 1,582 (mean age: 59 years, 43% male, 18% Black) participants, 45.7%, 21.7%, and 32.6% reported ideal, intermediate, or poor LTPA, respectively. High TV viewing was reported in 33.8% of participants, with 46.4% and 19.8% reporting medium or low TV viewing, respectively. Compared to poor LTPA, ideal LTPA in midlife was not associated with total wall volume ( ß =0.01, 95% CI: -0.01, 0.03), maximum carotid wall thickness ( ß =0.06, 95% CI: -0.08, 0.21), normalized wall index ( ß =-0.01, 95% CI: -0.03, 0.01), or maximum stenosis ( ß =-0.11, 95% CI: -1.98, 1.76). Low or middle, compared to high, TV viewing was also not associated with carotid artery measures of plaque burden. Compared to poor LTPA or high TV viewing, ideal LTPA (odds ratio (OR): 0.82, 95% CI: 0.55, 1.23) and low TV viewing (OR=0.90, 95% CI: 0.56, 1.44) was not associated with odds of lipid core presence, respectively., Conclusion: Overall, this study does not provide strong evidence for an association between LTPA and SB with carotid plaque measures., Competing Interests: The authors have no conflicts of interest., (© 2023 The Authors. Published by Elsevier B.V.)

Purpose: Sedentary time is ubiquitous in developed nations and is associated with deleterious health outcomes. Physical activity guidelines recommend reductions in sedentary time; however, quantitative guidelines that inform how often and how long sedentary time should be interrupted have not been provided. The purpose of this study was to examine the acute effects of multiple doses of a sedentary break intervention on cardiometabolic risk factors, concurrently evaluating efficacy of varying frequencies and durations of sedentary breaks., Methods: In a randomized crossover study, middle- and older-age adults ( n = 11) completed the following 8-h conditions on five separate days: 1 uninterrupted sedentary (control) condition and four acute (experimental) trials that entailed different sedentary break frequency/duration combinations: every 30 min for 1 min, every 30 min for 5 min, every 60 min for 1 min, and every 60 min for 5 min. Sedentary breaks entailed light-intensity walking. Glucose and blood pressure (BP) were measured every 15 and 60 min, respectively., Results: Compared with control, glucose incremental area under the curve was significantly attenuated only for the every 30 min for 5-min dose (-11.8[4.7]; P = 0.017). All sedentary break doses yielded significant net decreases in systolic BP from baseline compared with control ( P < 0.05). The largest reductions in systolic BP were observed for the every 60 min for 1 min (-5.2 [1.4] mm Hg) and every 30 min for 5 min (-4.3[1.4] mm Hg) doses., Conclusions: The present study provides important information concerning efficacious sedentary break doses. Higher-frequency and longer-duration breaks (every 30 min for 5 min) should be considered when targeting glycemic responses, whereas lower doses may be sufficient for BP lowering., (Copyright © 2023 by the American College of Sports Medicine.)

We formulate the estimation of monotone response surface of multiple factors as the inverse of an iteration of partially ordered classifier ensembles. Each ensemble (called PIPE-classifiers) is a projection of Bayes classifiers on the constrained space. We prove the inverse of PIPE-classifiers (iPIPE) exists, and propose algorithms to efficiently compute iPIPE by reducing the space over which optimisation is conducted. The methods are applied in analysis and simulation settings where the surface dimension is higher than what the isotonic regression literature typically considers. Simulation shows iPIPE-based credible intervals achieve nominal coverage probability and are more precise compared to unconstrained estimation., Competing Interests: conflict of interest The authors have no conflicts of interest to disclose.

While prenatal screening and testing have expanded substantially over the past decade and provide access to more genetic information, expectant parents are more likely to describe the diagnosis experience as negative than positive. In addition, the conversations that take place during these experiences sometimes reflect unconscious bias against people with disabilities. Consequently, an interdisciplinary committee of experts, including people with disabilities, family members, disability organization leaders, healthcare and genetics professionals, and bioethicists, reviewed selected published and gray literature comparing the current state of the administration of prenatal testing to the ideal state. Subsequently, the interdisciplinary team created recommendations for clinicians, public health agencies, medical organizations, federal agencies, and other stakeholders involved with administering prenatal screening and testing to create better patient experiences; conduct training for healthcare professionals; create, enforce, and fund policies and guidelines; and engage in more robust data collection and research efforts., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Introduction/purpose: Physical activity studies often utilize wearable devices to measure participants' habitual activity levels by averaging values across several valid observation days. These studies face competing demands-available resources and the burden to study participants must be balanced with the goal to obtain reliable measurements of a person's longer-term average. Information about the number of valid observation days required to reliably measure targeted metrics of habitual activity is required to inform study design., Methods: To date, the number of days required to achieve a desired level of aggregate long-term reliability (typically 0.80) has often been estimated by applying the Spearman-Brown Prophecy formula to short-term test-retest reliability data from studies with single, relatively brief observation windows. Our work, in contrast, utilizes a resampling-based approach to quantify the long-term test-retest reliability of aggregate measures of activity in a cohort of 79 participants who were asked to wear a FitBit Flex every day for approximately one year., Results: The conventional approach can produce reliability estimates that substantially overestimate the actual test-retest reliability. Six or more valid days of observation for each participant appear necessary to obtain 0.80 reliability for the average amount of time spent in light physical activity; 8 and 10 valid days are needed for sedentary time and moderate/vigorous activity respectively., Conclusion: Protocols that result in 7-10 valid observation days for each participant may be needed to obtain reliable measurements of key physical activity metrics., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Hilden et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Importance: Breath analysis has been explored as a noninvasive means to detect COVID-19. However, the impact of emerging variants of SARS-CoV-2, such as Omicron, on the exhaled breath profile and diagnostic accuracy of breath analysis is unknown., Objective: To evaluate the diagnostic accuracies of breath analysis on detecting patients with COVID-19 when the SARS-CoV-2 Delta and Omicron variants were most prevalent., Design, Setting, and Participants: This diagnostic study included a cohort of patients who had positive and negative test results for COVID-19 using reverse transcriptase polymerase chain reaction between April 2021 and May 2022, which covers the period when the Delta variant was overtaken by Omicron as the major variant. Patients were enrolled through intensive care units and the emergency department at the University of Michigan Health System. Patient breath was analyzed with portable gas chromatography., Main Outcomes and Measures: Different sets of VOC biomarkers were identified that distinguished between COVID-19 (SARS-CoV-2 Delta and Omicron variants) and non-COVID-19 illness., Results: Overall, 205 breath samples from 167 adult patients were analyzed. A total of 77 patients (mean [SD] age, 58.5 [16.1] years; 41 [53.2%] male patients; 13 [16.9%] Black and 59 [76.6%] White patients) had COVID-19, and 91 patients (mean [SD] age, 54.3 [17.1] years; 43 [47.3%] male patients; 11 [12.1%] Black and 76 [83.5%] White patients) had non-COVID-19 illness. Several patients were analyzed over multiple days. Among 94 positive samples, 41 samples were from patients in 2021 infected with the Delta or other variants, and 53 samples were from patients in 2022 infected with the Omicron variant, based on the State of Michigan and US Centers for Disease Control and Prevention surveillance data. Four VOC biomarkers were found to distinguish between COVID-19 (Delta and other 2021 variants) and non-COVID-19 illness with an accuracy of 94.7%. However, accuracy dropped substantially to 82.1% when these biomarkers were applied to the Omicron variant. Four new VOC biomarkers were found to distinguish the Omicron variant and non-COVID-19 illness (accuracy, 90.9%). Breath analysis distinguished Omicron from the earlier variants with an accuracy of 91.5% and COVID-19 (all SARS-CoV-2 variants) vs non-COVID-19 illness with 90.2% accuracy., Conclusions and Relevance: The findings of this diagnostic study suggest that breath analysis has promise for COVID-19 detection. However, similar to rapid antigen testing, the emergence of new variants poses diagnostic challenges. The results of this study warrant additional evaluation on how to overcome these challenges to use breath analysis to improve the diagnosis and care of patients.

Background: Daily 24-h sleep-wake cycles have important implications for health, however researcher preferences in choice and location of wearable devices for behavior measurement can make 24-h cycles difficult to estimate. Further, missing data due to device malfunction, improper initialization, and/or the participant forgetting to wear one or both devices can complicate construction of daily behavioral compositions. The Method for Activity Sleep Harmonization (MASH) is a process that harmonizes data from two different devices using data from women who concurrently wore hip (waking) and wrist (sleep) devices for ≥ 4 days., Methods: MASH was developed using data from 1285 older community-dwelling women (ages: 60-72 years) who concurrently wore a hip-worn ActiGraph GT3X + accelerometer (waking activity) and a wrist-worn Actiwatch 2 device (sleep) for ≥ 4 days (N = 10,123 days) at the same time. MASH is a two-tiered process using (1) scored sleep data (from Actiwatch) or (2) one-dimensional convolutional neural networks (1D CNN) to create predicted wake intervals, reconcile sleep and activity data disagreement, and create day-level night-day-night pairings. MASH chooses between two different 1D CNN models based on data availability (ActiGraph + Actiwatch or ActiGraph-only). MASH was evaluated using Receiver Operating Characteristic (ROC) and Precision-Recall curves and sleep-wake intervals are compared before (pre-harmonization) and after MASH application., Results: MASH 1D CNNs had excellent performance (ActiGraph + Actiwatch ROC-AUC = 0.991 and ActiGraph-only ROC-AUC = 0.983). After exclusions (partial wear [n = 1285], missing sleep data proceeding activity data [n = 269], and < 60 min sleep [n = 9]), 8560 days were used to show the utility of MASH. Of the 8560 days, 46.0% had ≥ 1-min disagreement between the devices or used the 1D CNN for sleep estimates. The MASH waking intervals were corrected (median minutes [IQR]: -27.0 [-115.0, 8.0]) relative to their pre-harmonization estimates. Most correction (-18.0 [-93.0, 2.0] minutes) was due to reducing sedentary behavior. The other waking behaviors were reduced a median (IQR) of -1.0 (-4.0, 1.0) minutes., Conclusions: Implementing MASH to harmonize concurrently worn hip and wrist devices can minimizes data loss and correct for disagreement between devices, ultimately improving accuracy of 24-h compositions necessary for time-use epidemiology.

Objectives: Derive latent profiles of accelerometry-measured moderate-vigorous physical activity (MVPA) for Hispanic/Latino adults, examine associations between latent MVPA profiles and neurocognition, and describe profiles via self-reported MVPA., Methods: Complex survey design methods were applied to cross-sectional data from 7,672 adults ages 45-74 years in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL; 2008-2011). MVPA was measured via hip-worn accelerometers. Latent profile analysis was applied to derive latent MVPA profiles (minutes/day of week). Neurocognition was assessed with the Brief-Spanish English Verbal Learning Test (B-SEVLT) Sum, B-SEVLT Recall, Controlled Oral Word Association Test (word fluency), and Digit Symbol Substitution (DSS) test. All tests were z-scored, and a global neurocognition score was generated by averaging across scores. Survey linear regression models were used to examine associations between latent MVPA profiles and neurocognitive measures. Self-reported MVPA domains were estimated (occupational, transportation, and recreational) for each latent profile., Results: Four latent MVPA profiles from the overall adult target population (18-74 years) were derived and putatively labeled: No MVPA, low, moderate, and high. Only the high MVPA profile (compared to moderate) was associated with lower global neurocognition. Sensitivity analyses using latent MVPA profiles with only participants aged 45-74 years showed similar profiles, but no associations between latent MVPA profiles and neurocognition. The occupational MVPA domain led in all latent MVPA profiles., Discussion: We found no consistent evidence to link accelerometry-measured MVPA profiles to neurocognitive function. Research to better characterize the role of high occupational MVPA in relation to neurocognition among Hispanic/Latino adults are needed., (Published by Oxford University Press on behalf of The Gerontological Society of America 2022.)

Purpose: Sedentary behavior is associated with poor physical function in older adults, which can lead to accelerated skeletal muscle aging (sarcopenia) and premature mortality. We examined the independent and joint effects of sedentary behavior and moderate to vigorous intensity physical activity (MVPA) with measures of physical functioning., Methods: We studied 5408 participants in the REasons for Geographic and Racial Differences in Stroke study who wore a hip-mounted accelerometer over seven consecutive days (2009-2013) and had self-reported and directly observed physical function (time walk, chair stand test) measured during an in-home visit conducted from 2013 to 2016., Results: Greater sedentary time was significantly associated with poorer chair stand and timed walk scores. Substituting 30 min of sedentary time with 30 min of MVPA was associated with significant improvements in chair stands (β -0.57; P = 0.007) and timed walk (β -0.36; P = 0.01). Similar, but less robust, findings were observed for reallocations of sedentary time to light-intensity physical activity. In joint association analyses, high sedentary time in combination with low MVPA (but not in combination with high MVPA) was associated with poorer physical function compared with the referent group (low sedentary time/high MVPA; P < 0.001 for all)., Conclusions: Greater time spent being sedentary was associated with worse physical functioning outcomes. However, reallocations of sedentary time to light-intensity physical activity, and especially MVPA, were associated with more favorable physical functioning. Interventions aimed to increase MVPA and reduce sedentary behavior should be a priority, especially among populations at greatest risk for sarcopenia and physical function decline., (Copyright © 2022 by the American College of Sports Medicine.)

Recent studies have revealed a critical role for natural Abs (NAbs) in antitumor immune responses. However, the role of NAbs in cancer immunosurveillance remains unexplored, mainly because of the lack of in vivo models that mimic the early recognition and elimination of transforming cells. In this article, we propose a role for NAbs in alerting the immune system against precancerous neoantigen-expressing cells immediately after they escape intrinsic tumor suppression mechanisms. We identify four distinct reproducible, trackable, MHC-matched neoantigen-expressing cell models that do not form tumors as the end point. This amplified readout in the critical window prior to tumor formation allows investigation of new mediators of cancer immunosurveillance. We found that neoantigen-expressing cells adoptively transferred in NAb-deficient mice persisted, whereas they were eliminated in wild-type mice, indicating that the circulating NAb repertoire alerts the immune system to the presence of transformed cells. Moreover, immunity is mounted against immunogenic and nonimmunogenic neoantigens contained in the NAb-tagged cells, regardless of whether the NAb directly recognizes the neoantigens. Beyond these neoantigen-expressing model systems, we observed a significantly greater tumor burden in chemically and virally induced tumor models in NAb-deficient mice compared with wild-type mice. Restoration of the NAb repertoire in NAb-deficient mice elicited the recognition and elimination of neoantigen-expressing cells and cancer. These data show that NAbs are required and sufficient for elimination of transformed cells early in tumorigenesis. These models can now be used to investigate how NAbs stimulate immunity via recognition receptors to eliminate precancerous cells., (Copyright © 2022 by The American Association of Immunologists, Inc.)

In this article we address the problem of estimating minimum effective doses in dose-finding clinical trials of multidimensional treatment. We are motivated by a behavioral intervention trial where we introduce sedentary breaks to subjects with a goal to reduce their glucose level monitored over 8 hours. Each sedentary break regimen is defined by two elements: break frequency and break duration. The trial aims to identify minimum combinations of frequency and duration that shift mean glucose, that is, the minimum effective dose (MED) combinations. The means of glucose reduction associated with the dose combinations are only partially ordered. To circumvent constrained estimation due to partial ordering, we propose estimating the MED by maximizing a weighted product of combinationwise posterior gains. The estimation adopts an asymmetric gain function, indexed by a decision parameter ϵ , which defines the relative gains of a true negative decision and a true positive decision. We also introduce an adaptive ϵ -tapering algorithm to be used in conjunction with the estimation method. Simulation studies show that using asymmetric gain with a carefully chosen ϵ is critical to keeping false discoveries low, while ϵ -tapering adds to the probability of identifying truly effective doses (i.e., true positives). Under an ensemble of scenarios for the sedentary break study, ϵ -tapering yields consistently high true positive rates across scenarios and achieves about 90% true positive rate, compared to 68% by a nonadaptive design with comparable false discovery rate.

Background: The joint associations of total and intensity-specific physical activity with obesity in relation to all-cause mortality risk are unclear., Methods: We included 34 492 adults (72% women, median age 62.1 years, 2034 deaths during follow-up) in a harmonised meta-analysis of eight population-based prospective cohort studies with mean follow-up ranging from 6.0 to 14.5 years. Standard body mass index categories were cross-classified with sample tertiles of device-measured total, light-to-vigorous and moderate-to-vigorous physical activity and sedentary time. In five cohorts with waist circumference available, high and low waist circumference was combined with tertiles of moderate-to-vigorous physical activity., Results: There was an inverse dose-response relationship between higher levels of total and intensity-specific physical activity and mortality risk in those who were normal weight and overweight. In individuals with obesity, the inverse dose-response relationship was only observed for total physical activity. Similarly, lower levels of sedentary time were associated with lower mortality risk in normal weight and overweight individuals but there was no association between sedentary time and risk of mortality in those who were obese. Compared with the obese-low total physical activity reference, the HRs were 0.59 (95% CI 0.44 to 0.79) for normal weight-high total activity and 0.67 (95% CI 0.48 to 0.94) for obese-high total activity. In contrast, normal weight-low total physical activity was associated with a higher risk of mortality compared with the obese-low total physical activity reference (1.28; 95% CI 0.99 to 1.67)., Conclusions: Higher levels of physical activity were associated with lower risk of mortality irrespective of weight status. Compared with obesity-low physical activity, there was no survival benefit of being normal weight if physical activity levels were low., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Importance: The amount and intensity of physical activity required to prevent stroke are yet to be fully determined because of previous reliance on self-reporting measures. Furthermore, the association between objectively measured time spent being sedentary as an independent risk factor for stroke is unknown., Objective: To investigate the associations of accelerometer-measured sedentary time and physical activity of varying intensity and duration with the risk of incident stroke., Design, Setting, and Participants: This cohort study involved participants who were enrolled in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study from February 5, 2003, to October 30, 2007. Accelerometer data were collected from 7607 Black and White adults 45 years or older in the contiguous US between May 12, 2009, and January 5, 2013. Data on other races and ethnicities were not collected for scientific and clinical reasons. By design, Black adults and residents of the southeastern US stroke belt and stroke buckle were oversampled. Data were analyzed from May 5, 2020, to November 11, 2021., Exposures: Sedentary time, light-intensity physical activity (LIPA), and moderate- to vigorous-intensity physical activity (MVPA) were measured using a hip-mounted accelerometer worn for 7 consecutive days and stratified by tertile for the analyses., Main Outcomes and Measures: Incident stroke., Results: Among 7607 participants, the mean (SD) age was 63.4 (8.5) years; 4145 participants (54.5%) were female, 2407 (31.6%) were Black, and 5200 (68.4%) were White. A total of 2523 participants (33.2%) resided in the stroke belt, and 1638 (21.5%) resided in the stroke buckle. Over a mean (SD) of 7.4 (2.5) years of follow-up, 286 incident stroke cases (244 ischemic [85.3%]) occurred. The fully adjusted hazard ratios (HRs) for incident stroke in the highest tertile compared with the lowest tertile were 0.74 (95% CI, 0.53-1.04; P = .08) for LIPA and 0.57 (95% CI, 0.38-0.84; P = .004) for MVPA. Higher sedentary time was associated with a 44% greater risk of incident stroke (HR, 1.44; 95% CI, 0.99-2.07; P = .04). When comparing the highest with the lowest tertile, mean sedentary bout duration was associated with a significantly greater risk of incident stroke (HR, 1.53; 95% CI, 1.10-2.12; P = .008). After adjustment for sedentary time, the highest tertile of unbouted MVPA (shorter bouts [1-9 minutes]) was associated with a significantly lower risk of incident stroke compared with the lowest tertile (HR, 0.62; 95% CI, 0.41-0.94; P = .02); however, bouted MVPA (longer bouts [at least 10 minutes]) was not (HR, 0.78; 95% CI, 0.53-1.15; P = .17). When expressed as continuous variables, sedentary time was positively associated with incident stroke risk (HR per 1-hour/day increase in sedentary time: 1.14; 95% CI, 1.02-1.28; P = .02), and LIPA was negatively associated with incident stroke risk (HR per 1-hour/day increase in LIPA: 0.86; 95% CI, 0.77-0.97; P = .02)., Conclusions and Relevance: In this cohort study, objectively measured LIPA, MVPA, and sedentary time were significantly and independently associated with incident stroke risk. Longer sedentary bout duration was also independently associated with an increased risk of incident stroke. These findings suggest that replacing sedentary time with LIPA, or even very short bouts of MVPA, may lower stroke risk, supporting the concept of moving more and sitting less as a beneficial stroke risk reduction strategy among adults.

Purpose of Review: Review the most recent evidence on the role of sedentary behavior in the prevention of cardiovascular disease (CVD)., Recent Findings: Prospective cohort studies continue to suggest a relationship between sedentary behavior and CVD, but the dose-response association, and the implications of sedentary pattern (vs. total volume) and context on CVD risk require further investigation. Most recent evidence suggests that physical activity influences the association between sedentary time and CVD risk, and that replacing sedentary time with other movement behaviors yields cardiometabolic benefits. Short-term intervention studies have further demonstrated that interrupting prolonged sitting with bouts of physical activity can elicit acute improvements on cardiometabolic biomarkers and vascular function relative to prolonged, uninterrupted sitting, albeit limited evidence exists on the long-term effects. More conclusive evidence regarding the implications of sedentary time on CVD risk is warranted before the optimal sedentary behavior reduction prescription for the prevention of CVD can be elucidated., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background and Purpose: We examined differences in the volume and pattern of physical activity (PA) and sedentary behavior between adults with and without stroke., Methods: We studied cohort members with an adjudicated or self-reported stroke (n=401) and age-, sex-, race-, region of residence-, and body mass index-matched participants without a history of stroke (n=1203) from the REGARDS study (Reasons for Geographic and Racial Differences in Stroke). Sedentary behavior (total volume and bouts), light-intensity PA, and moderate-to-vigorous-intensity PA were objectively measured for 7 days via hip-worn accelerometer., Results: Sedentary time (790.5±80.4 versus 752.4±81.9 min/d) and mean sedentary bout duration (15.7±12.6 versus 11.9±8.1 min/d) were higher and PA (light-intensity PA: 160.5±74.6 versus 192.9±73.5 min/d and moderate-to-vigorous-intensity PA: 9.0±11.9 versus 14.7±17.0 min/d) lower for stroke survivors compared with controls (P<0.001). Stroke survivors also accrued fewer activity breaks (65.5±21.9 versus 73.31±18.9 breaks/d) that were shorter (2.4±0.7 versus 2.7±0.8 minutes) and lower in intensity (188.4±60.8 versus 217.9±72.2 counts per minute) than controls (P<0.001)., Conclusions: Stroke survivors accrued a lower volume of PA, higher volume of sedentary time, and exhibited accrual patterns of more prolonged sedentary bouts and shorter, lower intensity activity breaks compared with persons without stroke.

Objective: To examine the joint associations of daily time spent in different intensities of physical activity, sedentary behaviour and sleep with all-cause mortality., Methods: Federated pooled analysis of six prospective cohorts with device-measured time spent in different intensities of physical activity, sedentary behaviour and sleep following a standardised compositional Cox regression analysis., Participants: 130 239 people from general population samples of adults (average age 54 years) from the UK, USA and Sweden., Main Outcome: All-cause mortality (follow-up 4.3-14.5 years)., Results: Studies using wrist and hip accelerometer provided statistically different results (I 2 =92.2%, Q-test p<0.001). There was no association between duration of sleep and all-cause mortality, HR=0.96 (95% CI 0.67 to 1.12). The proportion of time spent in moderate to vigorous physical activity was significantly associated with lower risk of all-cause mortality (HR=0.63 (95% CI 0.55 to 0.71) wrist; HR=0.93 (95% CI 0.87 to 0.98) hip). A significant association for the ratio of time spent in light physical activity and sedentary time was only found in hip accelerometer-based studies (HR=0.5, 95% CI 0.42 to 0.62). In studies based on hip accelerometer, the association between moderate to vigorous physical activity and mortality was modified by the balance of time spent in light physical activity and sedentary time., Conclusion: This federated analysis shows a joint dose-response association between the daily balance of time spent in physical activity of different intensities and sedentary behaviour with all-cause mortality, while sleep duration does not appear to be significant. The strongest association is with time spent in moderate to vigorous physical activity, but it is modified by the balance of time spent in light physical activity relative to sedentary behaviour., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY. Published by BMJ.)

Introduction: African Americans are disproportionately affected by high blood pressure, which may be associated with exposure to air pollutants, such as fine particulate matter and ozone., Methods: Among African American Jackson Heart Study participants, this study examined associations between 1-year and 3-year mean fine particulate matter and ozone concentrations with prevalent and incident hypertension at Visits 1 (2000-2004, n=5,191) and 2 (2005-2008, n=4,105) using log binomial regression. Investigators examined associations with systolic blood pressure, diastolic blood pressure, pulse pressure, and mean arterial pressure using linear regression and hierarchical linear models, adjusting for sociodemographic, behavioral, and clinical characteristics. Analyses were conducted in 2017-2019., Results: No associations were observed between fine particulate matter or ozone concentration and prevalent or incident hypertension. In linear models, an IQR increase in 1-year ozone concentration was associated with 0.67 mmHg higher systolic blood pressure (95% CI=0.27, 1.06), 0.42 mmHg higher diastolic blood pressure (95% CI=0.20, 0.63), and 0.50 mmHg higher mean arterial pressure (95% CI=0.26, 0.74). In hierarchical models, fine particulate matter was inversely associated with systolic blood pressure (-0.72, 95% CI= -1.31, -0.13), diastolic blood pressure (-0.69, 95% CI= -1.02, -0.36), and mean arterial pressure (-0.71, 95% CI= -1.08, -0.33). Attenuated associations were observed with 1-year concentrations and at Visit 1., Conclusions: Positive associations were observed between ozone and systolic blood pressure, diastolic blood pressure, and mean arterial pressure, and inverse associations between fine particulate matter and systolic blood pressure, diastolic blood pressure, and mean arterial pressure in an African American population with high (56%) prevalence of hypertension. Effect sizes were small and may not be clinically relevant., (Copyright © 2021. Published by Elsevier Inc.)

Wearable physical activity monitors (PAMs) have potential to positively influence physical activity. However, high rates of disengagement have been reported, which dampens enthusiasm, as these devices are unlikely to impact habitual physical activity if they are not worn for a sustained period of time. The purpose of this study was to identify demographic and device-use characteristics (e.g., data sharing) associated with sustained device engagement. Current PAM users (n = 418; mean age: 35.0 ± 12.5; 78% female) from across the USA were recruited online and completed a baseline web-based survey in 2015-2016 comprising questions about demographics and device use. Participants were followed-up again in 2017, at which time they reported whether or not they still used a PAM. Sustained PAM engagement was defined as those who continued use at follow-up. The median follow-up time was 15.5 (±3.7) months. In fully adjusted models, the following were significantly associated with long-term engagement: age (odds ratio [OR]: 1.03; 95% confidence interval [CI]: 1.01-1.05, p = .014), Hispanic ethnicity (OR: 3.67; 95% CI: 1.20-11.26, p = .023), running as a preferred exercise (OR: 1.82; 95% CI: 1.02-3.24, p = .043), wanting to monitor health variables as a reason for choosing to use a PAM (OR: 1.73; 95% CI: 1.02-2.92, p = .042), and sharing data from the PAM publicly on social media (e.g., Facebook and Twitter; OR: 5.11; 95% CI: 1.64-15.93, p = .005). A number of sociodemographic and use characteristics were associated with sustained device use over a median follow-up of 1.3 years. One modifiable factor that may lead to longer device engagement is encouraging users to share data publicly., (© Society of Behavioral Medicine 2019. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: Observational studies have linked occupational standing or walking to musculoskeletal pain. These prior studies, however, are flawed as few accounted for physical exertion; a potential confounder that accompanies many standing-based occupations. The purpose of this study was to examine the individual and joint associations of occupational standing/walking and exertion with musculoskeletal symptoms., Methods: Data for this analysis come from the 2015 National Health Interview Survey, a US nationally representative survey. Occupational standing/walking and exertion were assessed by self-report on a 5-point Likert scale. The presence of musculoskeletal symptoms (pain, aching and stiffness) for upper extremities (neck, shoulders, elbows, wrists and fingers), lower extremities (hips, knees, ankles and toes) and lower back was also assessed., Results: Occupational standing/walking was associated with a greater likelihood of upper extremity, lower extremity and lower back musculoskeletal symptoms; however, associations were attenuated and no longer significant with adjustment for exertion. When stratified by levels of occupational exertion, occupational standing/walking was associated with musculoskeletal symptoms only among the group with high exertion (eg, OR=1.69 (95% CI: 1.48 to 1.94) for lower back symptoms comparing high/high for standing or walking/exertion vs low/low). Among groups with low exertion, occupational standing/walking was not associated with musculoskeletal symptoms (eg, OR=1.00 (95% CI: 0.85 to 1.16) for lower back symptoms comparing high/low for standing or walking/exertion vs low/low)., Conclusion: Results from this US representative survey suggest that the association between occupational standing/walking and musculoskeletal symptoms is largely driven by the co-occurrence of occupational exertion and does not provide evidence that standing or walking incurs adverse musculoskeletal symptoms., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

The cross-stressor adaptation hypothesis of exercise training has not been investigated under real-life conditions. Using ecological momentary assessment, we tested whether usual exercise level moderates the relationship of self-reported anxiety to concurrent ambulatory heart rate (HR) and systolic/diastolic blood pressure (SBP/DBP). Participants (N = 832) completed 24-h ambulatory monitoring of HR/BP, using a brachial BP cuff that took readings at 28-min intervals. Anxiety levels were concurrently reported on a visual analog scale (VAS) using a Palm Pilot. Usual exercise behavior was assessed by a self-report questionnaire. Random coefficients linear regression models predicting momentary HR/BP readings from time-matched anxiety scores were estimated, yielding the average within-person effect (slope) of anxiety. The interaction of exercise level (i.e., no weekly exercise, 1-149, and ≥ 150 min/week; a between-person factor) with anxiety was added to the model in order to estimate the average anxiety slope for participants in each exercise category. The relationship of HR/BP to anxiety did not differ significantly among exercise categories, hence not providing evidence for the cross-stressor hypothesis. In an exploratory analysis of the difference in HR/BP between occasions when anxiety was in the top versus bottom person-specific quintiles of responses, the difference in HR (but not SBP or DBP) varied significantly by exercise level (F(2,625) = 4.92, p = 0.008). Though our pre-specified analysis did not support the hypothesis, we provide some post hoc evidence supporting the cross-stressor hypothesis of exercise training for the HR response to anxiety.

Objectives: To examine the joint associations of accelerometer-measured physical activity and sedentary time with all-cause mortality., Methods: We conducted a harmonised meta-analysis including nine prospective cohort studies from four countries. 44 370 men and women were followed for 4.0 to 14.5 years during which 3451 participants died (7.8% mortality rate). Associations between different combinations of moderate-to-vigorous intensity physical activity (MVPA) and sedentary time were analysed at study level using Cox proportional hazards regression analysis and summarised using random effects meta-analysis., Results: Across cohorts, the average time spent sedentary ranged from 8.5 hours/day to 10.5 hours/day and 8 min/day to 35 min/day for MVPA. Compared with the referent group (highest physical activity/lowest sedentary time), the risk of death increased with lower levels of MVPA and greater amounts of sedentary time. Among those in the highest third of MVPA, the risk of death was not statistically different from the referent for those in the middle (16%; 95% CI 0.87% to 1.54%) and highest (40%; 95% CI 0.87% to 2.26%) thirds of sedentary time. Those in the lowest third of MVPA had a greater risk of death in all combinations with sedentary time; 65% (95% CI 1.25% to 2.19%), 65% (95% CI 1.24% to 2.21%) and 263% (95% CI 1.93% to 3.57%), respectively., Conclusion: Higher sedentary time is associated with higher mortality in less active individuals when measured by accelerometry. About 30-40 min of MVPA per day attenuate the association between sedentary time and risk of death, which is lower than previous estimates from self-reported data., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The association between accelerometer-assessed physical activity and risk of diabetes remains unclear, especially among US Hispanic/Latino adults who have lower levels of physical activity and a higher diabetes burden compared with other racial/ethnical populations in the country., Objectives: To examine the association between accelerometer-assessed physical activity and incident diabetes in a US Hispanic/Latino population., Methods: We included 7280 participants of the Hispanic Community Health Study/Study of Latinos who aged 18-74 y and free of diabetes at baseline. Data on moderate-to-vigorous physical activity (MVPA) were collected using a 7-d accelerometer measurement. Incident diabetes was assessed after a mean ± SD of 6.0 ± 0.8 y using standard procedures including blood tests. RRs and 95% CIs of diabetes associated with MVPA were estimated using survey Poisson regressions. The associations of MVPA with 6-y changes in adiposity measures were also examined., Results: A total of 871 incident cases of diabetes were identified. MVPA was inversely and nonlinearly associated with risk of diabetes (P-nonlinearity = 0.006), with benefits accruing rapidly at the lower end of MVPA range (<30 min/d) and leveling off thereafter. The association differed by population age (P-interaction = 0.006). Higher MVPA was associated with lower risk of diabetes among individuals older than 50 y (RRQ4 versus Q1 = 0.50; 95% CI: 0.35, 0.73; P-trend < 0.001) but not among younger individuals (RRQ4 versus Q1 = 0.98; 95% CI: 0.66, 1.47; P-trend = 0.92). An inverse association between MVPA and 6-y gain in waist circumference was also limited to the older group (P-interaction with age < 0.001)., Conclusions: Among US Hispanic/Latino adults, baseline accelerometer-derived MVPA was inversely associated with incident diabetes only among individuals aged 50 y and older. Further studies are needed to confirm our findings and to clarify potential mechanisms underlying the possible age differences in the MVPA-diabetes association. This study was registered at clinicaltrials.gov as NCT02060344., (Copyright © The Author(s) on behalf of the American Society for Nutrition 2020.)

Background: A growing interest in reducing occupational sitting has resulted in public health efforts to encourage intermittent standing in workplaces. However, concerns have been raised that standing for prolonged periods may expose individuals to new health hazards, including lower limb atherosclerosis. These concerns have yet to be corroborated or refuted. The purpose of this study was to investigate the association between occupational standing and adverse changes in the Ankle-Brachial Index (ABI)., Methods: We studied 2121 participants from the Jackson Heart Study, a single-site community-based study of African-Americans residing in Jackson, MS. Occupational standing ('never/seldom', 'sometimes', 'often/always') was self-reported at baseline (2000-2004). ABI was measured at baseline and again at follow-up (2009-2013)., Results: Over a median follow-up of 8 years, 247 participants (11.6%) exhibited a significant decline in ABI (eg, ABI decline >0.15). In multivariable-adjusted models, higher occupational standing was not significantly associated with ABI decline (occupational standing sometimes vs never/seldom: OR 1.05; 95% CI 0.67, 1.66; occupational standing often/always vs never/seldom: OR 1.22; 95% CI 0.77, 1.94). Similarly, higher occupational standing was not associated with low ABI at follow-up reflective of peripheral artery disease (ABI <0.90) or high ABI at follow-up reflective of incompressible vessels (ABI >1.40)., Conclusions: In this community-based study of African-Americans, we found no evidence that occupational standing is deleteriously associated with adverse changes in ABI over a median follow-up of 8.0 years. These findings do not provide evidence implicating occupational standing as a risk factor for lower limb atherosclerosis., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The psychological factors underlying physical inactivity in vulnerable cardiac adult populations remain understudied. Anxiety sensitivity, a cognitive vulnerability defined as fear of the physical, cognitive, and social consequences of anxiety, may be an important modifiable determinant of physical inactivity. We examined the association of anxiety sensitivity, and each anxiety sensitivity subscale (physical, cognitive, and social concerns), with physical inactivity in adults with a history of myocardial infarction (MI)., Methods: Using cross-sectional data from a nationally representative survey of adults (N = 1417) in the USA who reported a health professional diagnosis of MI, we used weighted logistic regression models to evaluate the association between anxiety sensitivity (overall, and each subscale) and physical inactivity (self-reported exercise 0-1 day/week), with adjustment for age, gender, race, education, number of MIs, and depression., Results: Overall, 34.3% reported physical inactivity. Anxiety sensitivity was associated with greater odds of physical inactivity (OR = 1.01; 95% CI = 1.00, 1.02; p = .026). Of the subscales, only physical concerns were associated with physical inactivity (OR = 1.02; 95% CI = 1.01, 1.04; p = .008) in the final model. High vs. low fear of shortness of breath was most consistently associated with physical inactivity (OR = 1.49; 95% CI = 1.08, 2.06; p < .021)., Conclusion: Anxiety sensitivity, generally, and fear of the physical sensations of anxiety (i.e., "fear of shortness of breath"), specifically, are important correlates of physical inactivity in adults with a history of MI. Future research should replicate these findings and experimentally test whether cardiac rehabilitation interventions that include an adjunctive component targeting reduction of anxiety sensitivity overall, or specific somatic symptoms, improve physical activity in this population.

Introduction: Physical inactivity, high screen time, and short sleep are targets of public health initiatives for children. However, few data exist on how many U.S. children meet guidelines for these behaviors-data vital to inform which needs greater targeting. This study describes national prevalence estimates of U.S. children who meet physical activity, screen time, and sleep guidelines alone or in combination across each childhood year., Methods: This analysis (completed in 2019) used cross-sectional data from the 2016-2017 National Survey of Children's Health, a nationally representative sample of U.S. children. Child physical activity (days per week with ≥60 minutes), recreational screen time (hours per day of TV viewing and electronic device use), and sleep duration (hours per day) were assessed through parental report. Guidelines recommend ≥60 minutes per day of physical activity, ≤2 hours per day of screen time, and 9-12 hours per day of sleep for individuals aged 6-12 years (8-10 hours for those aged 13-17 years)., Results: Only 8.8% (95% CI=8.2%, 9.5%) of U.S. children meet all the 3 guidelines combined. Majority of children/adolescents attain the sleep guideline (86.0%, 95% CI=85.2%, 86.7%), but a lower proportion meet physical activity (23.0%, 95% CI=22.1%, 23.9%) or screen time (32.9%, 95% CI=31.9%, 33.8%) guidelines. A substantial age effect was identified, with prevalence of meeting each distinct guideline and all the 3 declining with age (p<0.001)., Conclusions: Few U.S. children meet all the 3 movement guidelines, with prevalence rates of children meeting guidelines declining with age. Although many meet sleep guidelines, few meet physical activity or screen time guidelines. Initiatives targeting physical activity and screen time, especially for adolescents, should be pursued., (Copyright © 2020 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.)

Endothelial dysfunction is a mechanism that may explain the link between prolonged sedentary time and cardiovascular disease. However, the relation between habitual sedentary behavior (SED) and endothelial function has yet to be explored., Purpose: The purpose of this study was to examine the association of accelerometer-measured SED with markers of endothelial cell health., Methods: Healthy adult participants (n=83; 43.4% male; 25.5 ± 5.8 years old) were examined. SED was measured for 7-days by accelerometer. Endothelial function measures included endothelium-dependent vasodilation (EDV); endothelial microparticles (EMPs) [CD62E+ and CD31+/CD42- EMPs]; and endothelial progenitor cells (EPCs) [CD34+/CD133+/KDR+ and CD34+/KDR+EPCs]. Participants were classified as having low or high SED based on a median split., Results: Participants in the low and high SED group spent a mean ± SD of 8.6 ± 1.1 and 11.1 ± 1.0 h/day in SED, respectively. No significant differences between the low and high SED groups were detected in mean [95% confidence interval (CI)] EDV (2.51 [2.21-2.81] vs. 2.36 [2.07-2.64], p =0.50), EMPs (CD62E+: 6.70 [6.55-6.84] vs. 6.56 [6.42-6.69], p =0.20; CD31+/CD42‒: 6.26 [6.10-6.42] vs. 6.18 [6.03-6.33], p =0.50), or EPCs (CD34+/KDR+: 11.91 [9.23-14.48]×10 -2 vs. 14.87 [12.41-17.32]×10 -2 , p =0.13); CD34+/CD133+/KDR+: 1.84 [1.28-2.39]×10 -2 vs. 2.17 [1.64-2.70]×10 -2 , p =0.43)., Conclusions: Among healthy adults, habitual SED was not associated with markers of endothelial cell health., Competing Interests: Disclosure of Interest: The authors report no conflict of interest. The results of the present study do not constitute endorsement by the American College of Sports Medicine.

Importance: Sedentary behavior is associated with several health outcomes, including diabetes, cardiovascular disease, and all-cause mortality. Less is known about the association between objectively measured sedentary behavior and cancer mortality, as well as the association with physical activity., Objective: To examine the association between accelerometer-measured sedentary behavior (total volume and accrual in prolonged, uninterrupted bouts) and cancer mortality., Design, Setting, and Participants: A prospective cohort study conducted in the contiguous US included 8002 black and white adults aged 45 years or older enrolled in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study. The present analysis was performed from April 18, 2019, to April 21, 2020., Exposures: Sedentary time, light-intensity physical activity (LIPA), and moderate- to vigorous-intensity physical activity (MVPA) were measured using a hip-mounted accelerometer worn for 7 consecutive days., Main Outcomes and Measures: Cancer mortality., Results: Of the 8002 study participants, 3668 were men (45.8%); mean (SD) age was 69.8 (8.5) years. Over a mean (SD) follow-up of 5.3 (1.5) years, 268 participants (3.3%) died of cancer. In multivariable-adjusted models, including MVPA, greater total sedentary time was associated with a greater risk of cancer mortality (tertile 2 vs tertile 1: hazard ratio [HR], 1.45; 95% CI, 1.00-2.11; tertile 3 vs tertile 1: HR, 1.52; 95% CI, 1.01-2.27). Longer sedentary bout duration was not significantly associated with greater cancer mortality risk: after adjustment for MVPA (tertile 2 vs tertile 1: HR, 1.26; 95% CI, 0.90-1.78; tertile 3 vs tertile 1: HR, 1.36; 95% CI, 0.96-1.93). Replacing 30 minutes of sedentary time with LIPA was significantly associated with an 8% (per 30 minutes: HR, 0.92; 95% CI, 0.86-0.97) lower risk of cancer mortality; MVPA was significantly associated with a 31% (per 30 minutes: HR, 0.69; 95% CI, 0.48-0.97) lower risk of cancer mortality., Conclusions and Relevance: In this cohort study, greater sedentary time, as measured with accelerometry, appeared to be independently associated with cancer mortality risk. Replacing sedentary time with either LIPA or MVPA may be associated with a lower risk of cancer mortality. These findings suggest that the total volume of sedentary behavior is a potential cancer mortality risk factor and support the public health message that adults should sit less and move more to promote longevity.

It is unclear whether children with Down syndrome have differing physical activity and sedentary behavior levels compared to typical children. This study addressed this evidence gap in a national sample. Physical activity/sedentary behavior were ascertained by parental report. Findings highlighted that children with Down syndrome were less likely to engage in regular physical activity compared to typical children and had the lowest likelihood of regular physical activity among all subgroups with developmental disabilities/special healthcare needs. Children with Down syndrome were also more likely to watch high volumes of television compared to typical children, although this was nonsignificant upon adjustment for general health. It was concluded that children with Down syndrome are in urgent need for interventions/programs that promote physical activity.

Background: Experimental evidence suggests that sedentary time (ST) may contribute to cardiovascular disease by eliciting detrimental hemodynamic changes in the lower limbs. However, little is known about objectively measured ST and lower extremity peripheral artery disease (PAD)., Methods: We included 7,609 Hispanic/Latinos (ages 45-74) from the Hispanic Community Health Study/Study of Latinos. PAD was measured using the ankle brachial index (≤0.9). ST was measured using accelerometry. We used multivariable logistic regression to assess associations of quartiles of ST and PAD, and then used the same logistic models with restricted cubic splines to investigate continuous nonlinear associations of ST and PAD. Models were sequentially adjusted for traditional PAD risk factors, leg pain, and moderate- to vigorous-intensity physical activity (MVPA)., Results: Median ST was 12.2 h/d, and 5.4% of individuals had PAD. In fully adjusted restricted cubic splines models accounting for traditional PAD risk factors, leg pain, and MVPA, ST had a significant overall (P = .048) and nonlinear (P = .024) association with PAD. A threshold effect was seen such that time spent above median ST was associated with higher odds of PAD. That is, compared to median ST, 1, 2, and 3 hours above median ST were associated with a PAD odds ratio of 1.16 (95% CI = 1.02-1.31), 1.44 (1.06-1.94), and 1.80 (1.11-2.90), respectively., Conclusions: Among Hispanic/Latino adults, ST was associated with higher odds of PAD, independent of leg pain, MVPA, and traditional PAD risk factors. Notably, we observed a threshold effect such that these associations were only observed at the highest levels of ST., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Adults with intellectual disabilities (IDs) have higher rates of morbidity and mortality compared with the general population, necessitating a need to identify modifiable targets for intervention to mitigate risk. While the benefits of leisure-time physical activity (PA) are well established in the general population; there is a dearth of evidence confirming its health benefits among adults with IDs. The purpose of this study was to examine the association between leisure-time PA and all-cause mortality among a population-based sample of adults with IDs., Methods: A total of 413 adults with IDs from 17 waves (1997-2014) of the National Health Interview Survey, a U.S. nationally representative survey, were studied. Minutes per week of leisure-time PA was ascertained by self-report and classified as poor, intermediate or ideal levels of PA., Results: Over a median follow-up of 7.2 years, 60 participants died. In a multivariable-adjusted model, higher levels of leisure-time PA were dose-dependently associated with a lower risk of all-cause mortality (P-trend = 0.008). The multivariable-adjusted hazard ratios (95% confidence interval) for all-cause mortality comparing participants with intermediate and ideal versus poor levels of PA were 0.43 (0.18, 1.04) and 0.30 (0.10, 0.87), respectively., Conclusion: These findings show that leisure-time PA confers mortality benefit in adults with IDs and should be considered as a priority target for promoting health and longevity in this population., (© 2019 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.)

Background: Emerging evidence suggests that parents of children with intellectual disabilities have poorer physical health than parents of typically developing children. However, it is unclear why. The purpose of this study was to examine differences in physical inactivity among a population-based sample of parents of children with and without Down syndrome., Methods: Data for this analysis come from 11 waves (2005-2016) of the National Health Interview Survey, a U.S. nationally representative survey. Minutes per week of leisure-time physical activity were ascertained by self-report with physical inactivity defined as reporting no leisure-time physical activity. Parents were classified as (1) parents of typically developing children, (2) parents of children with Down syndrome, (3) parents of children with a developmental disability that had a high functional impact (autism, cerebral palsy, vision impairment or hearing impairment), (4) parents of children with an intellectual or developmental disability, but who did not have Down syndrome or a high-impact developmental disabilities, and (5) parents of children with other special health care needs., Results: Parents of children with Down syndrome were more likely to be physically inactive compared with parents of typical children (odds ratio [OR]: 1.51 [95% confidence interval, CI: 1.08, 2.12]) and had the lowest likelihood among all subgroups of parents to children with developmental disabilities or special health care needs. Parents of children with Down syndrome also had a significantly greater likelihood of being physically inactive compared with parents of children with other special health care needs (OR: 1.56 [95% CI: 1.11, 2.19]), with developmental disabilities without high functional impact (OR: 1.58 [95% CI: 1.12, 2.24]) and with developmental disabilities with high functional impact (OR: 1.46 [95% CI: 1.03, 2.08])., Conclusion: Parents of children with Down syndrome are more likely to be physically inactive compared with parents of typically developing children and parents of children with other developmental disabilities or special health care needs. These findings suggest that parents of children with Down syndrome are a population in urgent need for interventions/programmes that promote physical activity, particularly as child well-being is linked to caregiver health., (© 2019 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.)

Objective: To examine the dose-response associations between accelerometer assessed total physical activity, different intensities of physical activity, and sedentary time and all cause mortality., Design: Systematic review and harmonised meta-analysis., Data Sources: PubMed, PsycINFO, Embase, Web of Science, Sport Discus from inception to 31 July 2018., Eligibility Criteria: Prospective cohort studies assessing physical activity and sedentary time by accelerometry and associations with all cause mortality and reported effect estimates as hazard ratios, odds ratios, or relative risks with 95% confidence intervals., Data Extraction and Analysis: Guidelines for meta-analyses and systematic reviews for observational studies and PRISMA guidelines were followed. Two authors independently screened the titles and abstracts. One author performed a full text review and another extracted the data. Two authors independently assessed the risk of bias. Individual level participant data were harmonised and analysed at study level. Data on physical activity were categorised by quarters at study level, and study specific associations with all cause mortality were analysed using Cox proportional hazards regression analyses. Study specific results were summarised using random effects meta-analysis., Main Outcome Measure: All cause mortality., Results: 39 studies were retrieved for full text review; 10 were eligible for inclusion, three were excluded owing to harmonisation challenges (eg, wrist placement of the accelerometer), and one study did not participate. Two additional studies with unpublished mortality data were also included. Thus, individual level data from eight studies (n=36 383; mean age 62.6 years; 72.8% women), with median follow-up of 5.8 years (range 3.0-14.5 years) and 2149 (5.9%) deaths were analysed. Any physical activity, regardless of intensity, was associated with lower risk of mortality, with a non-linear dose-response. Hazards ratios for mortality were 1.00 (referent) in the first quarter (least active), 0.48 (95% confidence interval 0.43 to 0.54) in the second quarter, 0.34 (0.26 to 0.45) in the third quarter, and 0.27 (0.23 to 0.32) in the fourth quarter (most active). Corresponding hazards ratios for light physical activity were 1.00, 0.60 (0.54 to 0.68), 0.44 (0.38 to 0.51), and 0.38 (0.28 to 0.51), and for moderate-to-vigorous physical activity were 1.00, 0.64 (0.55 to 0.74), 0.55 (0.40 to 0.74), and 0.52 (0.43 to 0.61). For sedentary time, hazards ratios were 1.00 (referent; least sedentary), 1.28 (1.09 to 1.51), 1.71 (1.36 to 2.15), and 2.63 (1.94 to 3.56)., Conclusion: Higher levels of total physical activity, at any intensity, and less time spent sedentary, are associated with substantially reduced risk for premature mortality, with evidence of a non-linear dose-response pattern in middle aged and older adults., Systematic Review Registration: PROSPERO CRD42018091808., Competing Interests: Competing interests: All authors have completed the ICMJE uniform disclosure form and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)