Relationship of device measured physical activity type and posture with cardiometabolic health markers: pooled dose-response associations from the Prospective Physical Activity, Sitting and Sleep Consortium

AIMS/HYPOTHESIS

The aim of this study was to examine the dose-response associations of device-measured physical activity types and postures (sitting and standing time) with cardiometabolic health.

METHODS

We conducted an individual participant harmonised meta-analysis of 12,095 adults (mean ± SD age 54.5±9.6 years; female participants 54.8%) from six cohorts with thigh-worn accelerometry data from the Prospective Physical Activity, Sitting and Sleep (ProPASS) Consortium. Associations of daily walking, stair climbing, running, standing and sitting time with a composite cardiometabolic health score (based on standardised z scores) and individual cardiometabolic markers (BMI, waist circumference, triglycerides, HDL-cholesterol, HbA1c and total cholesterol) were examined cross-sectionally using generalised linear modelling and cubic splines.

RESULTS

We observed more favourable composite cardiometabolic health (i.e. z score <0) with approximately 64 min/day walking (z score [95% CI] -0.14 [-0.25, -0.02]) and 5 min/day stair climbing (-0.14 [-0.24, -0.03]). We observed an equivalent magnitude of association at 2.6 h/day standing. Any amount of running was associated with better composite cardiometabolic health. We did not observe an upper limit to the magnitude of the dose-response associations for any activity type or standing. There was an inverse dose-response association between sitting time and composite cardiometabolic health that became markedly less favourable when daily durations exceeded 12.1 h/day. Associations for sitting time were no longer significant after excluding participants with prevalent CVD or medication use. The dose-response pattern was generally consistent between activity and posture types and individual cardiometabolic health markers.

CONCLUSIONS/INTERPRETATION

In this first activity type-specific analysis of device-based physical activity, ~64 min/day of walking and ~5.0 min/day of stair climbing were associated with a favourable cardiometabolic risk profile. The deleterious associations of sitting time were fully attenuated after exclusion of participants with prevalent CVD and medication use. Our findings on cardiometabolic health and durations of different activities of daily living and posture may guide future interventions involving lifestyle modification.

Feasibility and acceptability of a cohort study baseline data collection of device-measured physical behaviors and cardiometabolic health in Saudi Arabia: expanding the Prospective Physical Activity, Sitting and Sleep consortium (ProPASS) in the Middle East

BACKGROUND

Physical behaviors such physical activity, sedentary behavior, and sleep are associated with mortality, but there is a lack of epidemiological data and knowledge using device-measured physical behaviors.

PURPOSE

To assess the feasibility of baseline data collection using the Prospective Physical Activity, Sitting, and Sleep consortium (ProPASS) protocols in the specific context of Saudi Arabia. ProPASS is a recently developed global platform for collaborative research that aims to harmonize retrospective and prospective data on device-measured behaviors and health. Using ProPASS methods for collecting data to perform such studies in Saudi Arabia will provide standardized data from underrepresented countries.

METHOD

This study explored the feasibility of baseline data collection in Saudi Arabia between November and December 2022 with a target recruitment of 50 participants aged ≥ 30 years. Established ProPASS methods were used to measure anthropometrics, measure blood pressure, collect blood samples, carry out physical function test, and measure health status and context of physical behaviors using questionnaires. The ActivPal™ device was used to assess physical behaviors and the participants were asked to attend two sessions at (LHRC). The feasibility of the current study was assessed by evaluating recruitment capability, acceptability, suitability of study procedures, and resources and abilities to manage and implement the study. Exit interviews were conducted with all participants.

RESULT

A total of 75 participants expressed an interest in the study, out of whom 54 initially agreed to participate. Ultimately, 48 participants were recruited in the study (recruitment rate: 64%). The study completion rate was 87.5% of the recruited participants; 95% participants were satisfied with their participation in the study and 90% reported no negative feelings related to participating in the study. One participant reported experiencing moderate skin irritation related to placement of the accelerometer. Additionally, 96% of participants expressed their willingness to participate in the study again.

CONCLUSION

Based on successful methodology, data collection results, and participants' acceptability, the ProPASS protocols are feasible to administer in Saudi Arabia. These findings are promising for establishing a prospective cohort in Saudi Arabia.

Occupational physical activity, all-cause, cardiovascular disease, and cancer mortality in 349,248 adults: Prospective and longitudinal analyses of the MJ Cohort

BACKGROUND

Evidence on the health benefits of occupational physical activity (OPA) is inconclusive. We examined the associations of baseline OPA and OPA changes with all-cause, cardiovascular disease (CVD), and cancer mortality and survival times.

METHODS

This study included prospective and longitudinal data from the MJ Cohort, comprising adults over 18 years recruited in 1998-2016. 349,248 adults (177,314 women) with baseline OPA, of whom 105,715 (52,503 women) had 2 OPA measures at 6.3 ± 4.2 (mean ± SD) years apart. Exposures were baseline OPA, OPA changes, and baseline leisure-time physical activity.

RESULTS

Over a mean mortality follow-up of 16.2 ± 5.5 years for men and 16.4 ± 5.4 years for women, 11,696 deaths (2033 of CVD and 4631 of cancer causes) in men and 8980 deaths (1475 of CVD and 3689 of cancer causes) in women occurred. Combined moderately heavy/heavy baseline OPA was beneficially associated with all-cause mortality in men (multivariable-adjusted hazard ratio (HR) = 0.93, 95% confidence interval (95%CI): 0.89-0.98 compared to light OPA) and women (HR = 0.86, 95%CI: 0.79-0.93). Over a mean mortality follow-up of 12.5 ± 4.6 years for men and 12.6 ± 4.6 years for women, OPA decreases in men were detrimentally associated (HR = 1.16, 95%CI: 1.01-1.33) with all-cause mortality, while OPA increases in women were beneficially (HR = 0.83, 95%CI: 0.70-0.97) associated with the same outcome. Baseline or changes in OPA showed no associations with CVD or cancer mortality.

CONCLUSION

Higher baseline OPA was beneficially associated with all-cause mortality risk in both men and women. Our longitudinal OPA analyses partly confirmed the prospective findings, with some discordance between sex groups.

Do the associations of daily steps with mortality and incident cardiovascular disease differ by sedentary time levels? A device-based cohort study

OBJECTIVES

This study aims to examine the associations of daily step count with all-cause mortality and incident cardiovascular disease (CVD) by sedentary time levels and to determine if the minimal and optimal number of daily steps is modified by high sedentary time.

METHODS

Using data from the UK Biobank, this was a prospective dose-response analysis of total daily steps across low (<10.5 hours/day) and high (≥10.5 hours/day) sedentary time (as defined by the inflection point of the adjusted absolute risk of sedentary time with the two outcomes). Mortality and incident CVD was ascertained through 31 October 2021.

RESULTS

Among 72 174 participants (age=61.1±7.8 years), 1633 deaths and 6190 CVD events occurred over 6.9 (±0.8) years of follow-up. Compared with the referent 2200 steps/day (5th percentile), the optimal dose (nadir of the curve) for all-cause mortality ranged between 9000 and 10 500 steps/day for high (HR (95% CI)=0.61 (0.51 to 0.73)) and low (0.69 (0.52 to 0.92)) sedentary time. For incident CVD, there was a subtle gradient of association by sedentary time level with the lowest risk observed at approximately 9700 steps/day for high (0.79 (0.72 to 0.86)) and low (0.71 (0.61 to 0.83)) sedentary time. The minimal dose (steps/day associated with 50% of the optimal dose) of daily steps was between 4000 and 4500 steps/day across sedentary time groups for all-cause mortality and incident CVD.

CONCLUSIONS

Any amount of daily steps above the referent 2200 steps/day was associated with lower mortality and incident CVD risk, for low and high sedentary time. Accruing 9000-10 500 steps/day was associated with the lowest mortality risk independent of sedentary time. For a roughly equivalent number of steps/day, the risk of incident CVD was lower for low sedentary time compared with high sedentary time.

Leisure-time physical activity and all-cause mortality and cardiovascular disease in adults with type 2 diabetes: Cross-country comparison of cohort studies

PURPOSE

This study aimed to quantify the dose-response association and the minimal effective dose of leisure-time physical activity (PA) to prevent mortality and cardiovascular disease in adults with type 2 diabetes.

METHODS

Cross-country comparison of 2 prospective cohort studies including 14,913 and 17,457 population-based adults with type 2 diabetes from the UK and China. Baseline leisure-time PA was self-reported and categorized by metabolic equivalent hours per week (MET-h/week) according to World Health Organization recommendations: none, below recommendation (>0-7.49 MET-h/week); at recommended level (7.5-14.9 MET-h/week); above recommendation (≥15 MET-h/week). Mortality and cardiovascular disease data were obtained from national registries.

RESULTS

During a median follow-up of 12.4 and 9.7 years, in the UK and China cohorts, repectively, higher levels of leisure-time PA were inversely associated with all-cause (1571 and 2351 events) and cardiovascular mortality (392 and 1060 events), mostly consistent with a linear dose-response relationship. PA below, at, and above recommendations, compared with no activity, yielded all-cause mortality hazard ratios of 0.94 (95% confidence interval (95%CI): 0.79-1.12), 0.90 (95%CI: 0.74-1.10), and 0.85 (95%CI: 0.70-1.02) in British adults and 0.87 (95%CI: 0.68-1.10), 0.88 (95%CI: 0.74-1.03), and 0.77 (95%CI: 0.70-0.85) in Chinese adults. Associations with cardiovascular mortality were more pronounced in British adults (0.80 (95%CI: 0.58-1.11), 0.75 (95%CI: 0.52-1.09), and 0.69 (95%CI: 0.48-0.97)) but less pronounced in Chinese adults (1.06 (95%CI: 0.76-1.47), 1.01 (95%CI: 0.80-1.28), and 0.79 (95%CI: 0.69-0.92)). PA at recommended levels was not associated with lower rates of major adverse cardiovascular events (2345 and 4458 events).

CONCLUSION

Leisure-time PA at the recommended levels was not convincingly associated with lower mortality and had no association with risk of major adverse cardiovascular events in British or Chinese adults with type 2 diabetes. Leisure-time PA above current recommendations may be needed to prevent cardiovascular disease and premature mortality in adults with type 2 diabetes.

Global prevalence of cardiovascular risk factors based on the Life's Essential 8 score: an overview of systematic reviews and meta-analysis

Cardiovascular health (CVH) is a critical issue for global health. However, no previous study has determined the prevalence of cardiovascular risk factors based on the American Heart Association's (AHA) Life's Essential 8 (LE8). Therefore, we aimed to estimate the global prevalence of the eight cardiovascular risk factors identified in the LE8. A systematic search of systematic reviews with meta-analysis on cardiovascular risk factors covering data reported between 2000 and 2019 was conducted on PubMed, Epistemonikos, and the Cochrane Library until 1 May 2023. After applying exclusion criteria, 79 studies remained in the final selection for the narrative synthesis in the systematic review, of which 33 of them were used in the meta-analysis which included 2 555 639 participants from 104 countries. The overall pooled prevalence of cardiovascular risk factors was as follows: insufficient physical activity, 26.3% (95% CI 2.3%-63.4%), no adherence to a healthy diet, 34.1% (95% CI 5.8%-71.2%), nicotine exposure, 15.4% (95% CI 10.4%-21.2%), insufficient sleep quality, 38.5% (95% CI 14.0%-66.7%), obesity, 17.3% (95% CI 6.1%-32.6%), dyslipidemia, 34.1% (95% CI 33.8%-34.4%), diabetes, 12.0% (95% CI 7.0%-18.2%), and hypertension, 29.4% (95% CI 23.3%-35.8%). These results warrant prevention strategies aimed at reducing insufficient sleep quality, and no adherence to a healthy diet as leading cardiovascular risk factors worldwide. The high prevalence of hypertension among children and adults is concerning and should also be adequately addressed through global policies.

Effect of exercise for depression: systematic review and network meta-analysis of randomised controlled trials

OBJECTIVE

To identify the optimal dose and modality of exercise for treating major depressive disorder, compared with psychotherapy, antidepressants, and control conditions.

DESIGN

Systematic review and network meta-analysis.

METHODS

Screening, data extraction, coding, and risk of bias assessment were performed independently and in duplicate. Bayesian arm based, multilevel network meta-analyses were performed for the primary analyses. Quality of the evidence for each arm was graded using the confidence in network meta-analysis (CINeMA) online tool.

DATA SOURCES

Cochrane Library, Medline, Embase, SPORTDiscus, and PsycINFO databases.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Any randomised trial with exercise arms for participants meeting clinical cut-offs for major depression.

RESULTS

218 unique studies with a total of 495 arms and 14 170 participants were included. Compared with active controls (eg, usual care, placebo tablet), moderate reductions in depression were found for walking or jogging (n=1210, κ=51, Hedges' g -0.62, 95% credible interval -0.80 to -0.45), yoga (n=1047, κ=33, g -0.55, -0.73 to -0.36), strength training (n=643, κ=22, g -0.49, -0.69 to -0.29), mixed aerobic exercises (n=1286, κ=51, g -0.43, -0.61 to -0.24), and tai chi or qigong (n=343, κ=12, g -0.42, -0.65 to -0.21). The effects of exercise were proportional to the intensity prescribed. Strength training and yoga appeared to be the most acceptable modalities. Results appeared robust to publication bias, but only one study met the Cochrane criteria for low risk of bias. As a result, confidence in accordance with CINeMA was low for walking or jogging and very low for other treatments.

CONCLUSIONS

Exercise is an effective treatment for depression, with walking or jogging, yoga, and strength training more effective than other exercises, particularly when intense. Yoga and strength training were well tolerated compared with other treatments. Exercise appeared equally effective for people with and without comorbidities and with different baseline levels of depression. To mitigate expectancy effects, future studies could aim to blind participants and staff. These forms of exercise could be considered alongside psychotherapy and antidepressants as core treatments for depression.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018118040.

Joint associations of device-measured physical activity and abdominal obesity with incident cardiovascular disease: a prospective cohort study

OBJECTIVE

To examine the joint associations between physical activity and abdominal obesity with the risk of cardiovascular disease (CVD) events.

METHODS

We included 70 830 UK Biobank participants (mean age±SD=61.6 ± 7.9 years; 56.4% women) with physical activity measured by wrist-worn accelerometers and without major chronic diseases. Participants were jointly categorised into six groups based on their physical activity level (tertiles of total volume and specific intensity levels) and presence or absence of abdominal obesity based on measured waist circumference. Associations with incident CVD (fatal and non-fatal events) were determined using proportional subdistribution hazard models with multivariable adjustment.

RESULTS

After excluding events during the first 2 years of follow-up, participants were followed for a median of 6.8 years, during which 2795 CVD events were recorded. Compared with the low abdominal adiposity and highest tertile of physical activity, abdominal obesity was associated with higher risk of incident CVD, especially in those with low levels of vigorous-intensity physical activity (HR 1.42, 95% CI 1.22 to 1.64). Approximately 500 min per week of moderate-to-vigorous intensity and approximately 30-35 min of vigorous-intensity physical activity offset the association of abdominal obesity and the risk of having a CVD event.

CONCLUSION

Physical activity equivalent to approximately 30-35 min of vigorous intensity per week appears to offset the association between abdominal obesity and incident CVD. About 15 times more physical activity of at least moderate intensity is needed to achieve similar results.

Association of physical behaviours with sarcopenia in older adults: a systematic review and meta-analysis of observational studies

BACKGROUND

Physical behaviours (ie, physical activity and sedentary behaviour) might have a role in the development of sarcopenia, although the evidence is unclear. We aimed to explore the association of total and intensity-specific levels of physical activity and sedentary behaviour with sarcopenia and its components (ie, muscle mass, muscle strength, and physical performance) in older adults.

METHODS

We conducted a systematic review and meta-analysis and searched MEDLINE (via PubMed), Scopus, and Web of Science from inception to July 26, 2022, for peer-reviewed, observational studies or baseline data from randomised clinical trials conducted in older adults (ie, individual age ≥60 years or mean age ≥65 years) and published in English that reported on the association of physical activity or sedentary behaviour or both with sarcopenia (or its determinants: muscle mass or strength, and physical performance). Physical activity and sedentary behaviour were measured by any method. The main outcome was sarcopenia, which could be diagnosed by any means. Estimates were extracted and pooled using Bayesian meta-analytic models and publication bias was assessed using the Egger's test. This study is registered with PROSPERO, CRD42022315865.

FINDINGS

We identified 15 766 records, of which 124 studies (230 174 older adults; 121 301 [52·7%] were female and 108 873 [47·3%] were male) were included in the systematic review. 86 studies were subsequently included in the meta-analysis. Higher levels of total physical activity were inversely associated with sarcopenia both cross-sectionally (21 studies, n=59 572; odds ratio 0·49, 95% credible interval 0·37-0·62) and longitudinally (four studies, n=7545; 0·51, 0·27-0·94). A protective association was also identified for moderate-to-vigorous physical activity in cross-sectional research (five studies, n=6787; 0·85, 0·71-0·99), whereas no association was identified for the remaining physical behaviours (ie, steps, light physical activity, or sedentary behaviour).

INTERPRETATION

Total and moderate-to-vigorous physical activity are inversely associated with sarcopenia. These findings might support the importance of moderate-to-vigorous, rather than light, intensity physical activity-based interventions to prevent sarcopenia.

FUNDING

None.

TRANSLATION

For the Spanish translation of the abstract see Supplementary Materials section.

Optimal Dose and Type of Physical Activity to Improve Glycemic Control in People Diagnosed With Type 2 Diabetes: A Systematic Review and Meta-analysis

BACKGROUND

The optimal dose or type of physical activity to control glycosylated hemoglobin (HbA1c) in people with diabetes remains unknown. Current guidelines do not include consideration of baseline HbA1c for activity prescription.

PURPOSE

To examine the dose-response relationship between physical activity and HbA1c (%) in individuals with type 2 diabetes.

DATA SOURCES

A systematic search was performed in Embase, MEDLINE, Scopus, CINAHL, SPORTDiscus, and Web of Science.

STUDY SELECTION

We included trials that involved participants diagnosed with type 2 diabetes that included any type of physical activity as intervention.

DATA EXTRACTION

Pre- and postintervention HbA1c data, population and interventions characteristics, and descriptive statistics were collected to calculate change scores for each study arm.

DATA SYNTHESIS

We used Bayesian random-effects meta-analyses to summarize high-quality evidence from 126 studies (6,718 participants). The optimal physical activity dose was 1,100 MET min/week, resulting in HbA1c reductions, ranging from -1.02% to -0.66% in severe uncontrolled diabetes, from -0.64% to -0.49% in uncontrolled diabetes, from -0.47% to -0.40% in controlled diabetes, and from -0.38% to -0.24% in prediabetes.

LIMITATIONS

The time required to achieve these HbA1c reductions could not be estimated due to the heterogeneity between interventions' duration and protocols and the interpersonal variability of this outcome.

CONCLUSIONS

The result of this meta-analysis provide key information about the optimal weekly dose of physical activity for people with diabetes with consideration of baseline HbA1c level, and the effectiveness of different types of active interventions. These results enable clinicians to prescribe tailored physical activity programs for this population.

An umbrella review of the benefits and risks associated with youths' interactions with electronic screens

The influence of electronic screens on the health of children and adolescents and their education is not well understood. In this prospectively registered umbrella review (PROSPERO identifier CRD42017076051 ), we harmonized effects from 102 meta-analyses (2,451 primary studies; 1,937,501 participants) of screen time and outcomes. In total, 43 effects from 32 meta-analyses met our criteria for statistical certainty. Meta-analyses of associations between screen use and outcomes showed small-to-moderate effects (range: r = -0.14 to 0.33). In education, results were mixed; for example, screen use was negatively associated with literacy (r = -0.14, 95% confidence interval (CI) = -0.20 to -0.09, P ≤ 0.001, k = 38, N = 18,318), but this effect was positive when parents watched with their children (r = 0.15, 95% CI = 0.02 to 0.28, P = 0.028, k = 12, N = 6,083). In health, we found evidence for several small negative associations; for example, social media was associated with depression (r = 0.12, 95% CI = 0.05 to 0.19, P ≤ 0.001, k = 12, N = 93,740). Limitations of our review include the limited number of studies for each outcome, medium-to-high risk of bias in 95 out of 102 included meta-analyses and high heterogeneity (17 out of 22 in education and 20 out of 21 in health with I2 > 50%). We recommend that caregivers and policymakers carefully weigh the evidence for potential harms and benefits of specific types of screen use.

Dose-response association between cardiovascular health and mortality in cancer survivors

BACKGROUND

There is little knowledge on the dose-response association between cardiovascular health (CVH) and risk of all-cause, cardiovascular disease (CVD) and cancer deaths among cancer survivors.

AIMS

We aimed to examine the dose-response association of CVH with all-cause, CVD, and cancer mortality.

METHODS

A total of 1701 US adult cancer survivors were followed-up during a median of 7.3 (IQR 4.0-10.2) years from 2007 to 2018 through the National Health and Nutrition Examination Survey (NHANES). We used the American Heart Association´s (AHA) Life´s Essential 8 (LE8) as a proxy for CVH.

RESULTS

Restricted cubic spline models indicated a close to inverse linear shape for the dose-response association between LE8 score and all-cause mortality with significant risk reductions within the range between 61.25 (Hazard ratio [HR]: 0.76, 95% CI, 0.59-0.98) and 100 points (HR: 0.28, 95%CI, 0.12-0.62), and a curvilinear shape for the dose-response association between LE8 score and CVD deaths with significant risk reductions within the range between 50.25 (HR: 0.72, 95% CI, 0.52-0.99) and 90.25 points (HR: 0.15, 95%CI, 0.02-0.98). No significant dose-response association was observed between LE8 and cancer deaths.

CONCLUSIONS

Our study showed a close to inverse relationship between higher LE8 and risk of death from all cause, an inverse curvilinear relationship between higher LE8 and the risk for CVD death, and a non-significant association between higher LE8 and the risk of cancer death among US adult cancer survivors, which may translate to a substantial number of annual averted deaths and thus important public health implications.

The Equality Paradox: Gender Equality Intensifies Male Advantages in Adolescent Subjective Well-Being

Individuals' subjective well-being (SWB) is an important marker of development and social progress. As psychological health issues often begin during adolescence, understanding the factors that enhance SWB among adolescents is critical to devising preventive interventions. However, little is known about how institutional contexts contribute to adolescent SWB. Using Programme for International Student Assessment (PISA) 2015 and 2018 data from 78 countries (N = 941,475), we find that gender gaps in adolescents' SWB (life satisfaction, positive and negative affect) are larger in more gender-equal countries. Results paradoxically indicated that gender equality enhances boys' but not girls' SWB, suggesting that greater gender equality may facilitate social comparisons across genders. This may lead to an increased awareness of discrimination against females and consequently lower girls' SWB, diluting the overall benefits of gender equality. These findings underscore the need for researchers and policy-makers to better understand macro-level factors, beyond objective gender equality, that support girls' SWB.

Moderate and vigorous leisure time physical activity in older adults and Alzheimer's disease-related mortality in the USA: a dose-response, population-based study

BACKGROUND

Data for the dose-response associations of moderate physical activity (MPA) and vigorous physical activity (VPA) with Alzheimer's disease-related mortality are scarce. We aimed to examine the prospective associations of such activity with Alzheimer's disease-related mortality.

METHODS

In this dose-response, population-based study, we pooled data from 22 consecutive waves of the US National Health Interview Survey (from 1997 to 2018). Participants aged 68 years or older were included in the study if they had full data for physical or muscle-strengthening activity, chronic conditions, functional limitations, marital status, education level, alcohol consumption, smoking status, and BMI, and follow-up time after study entry. Participants were linked to the National Death Index until Dec 31, 2019. We defined Alzheimer's disease-related mortality as a leading cause by using the G-30 code of the International Statistical Classification of Diseases and Related Health Problems tenth revision. Information on MPA and VPA was self-reported, with participants asked to answer four questions on the frequency and duration of both types of physical activity. We calculated hazard ratios (HRs) and used restricted cubic splines models to assess dose-response associations, and we estimated the annual number of Alzheimer's disease-related deaths that could be prevented through physical activity using adjusted population attributable fractions.

FINDINGS

After excluding 21 377 participants, 91 298 adults were included in the analysis. The weighted mean participant age was 75·8 years (SE 0·0); 55 658 (56·7%) were female and 76 796 (87·6%) were White (weighted percentages). The median follow-up was 6·5 years (IQR 3·6-10·7), corresponding to 703 393 person-years. 2176 (2·4%) participants died due to Alzheimer's disease as the leading cause. For MPA, we did not find a significant dose-response association with Alzheimer's disease-related mortality, whereas for VPA, we observed a significant L-shaped association between 20 weekly min and 190 weekly min. For VPA, we identified a minimal amount (ie, 50% of the optimal amount) at 40 min/week (HR 0·91, 95% CI 0·84-0·95) and an optimal amount (ie, the nadir of the curve) at 140 min/week (0·79, 0·66-0·95) for reducing Alzheimer's disease-related mortality. For the USA, we estimated that 40 weekly min of VPA would prevent 12 238 deaths per year (95% CI 89-23 172) and 140 weekly min of VPA would prevent 37 710 deaths per year (311-63 567), compared with a scenario in which US adults did not do any VPA.

INTERPRETATION

These findings might inform future guidelines for preventing Alzheimer's disease-related mortality by emphasising the importance of VPA over MPA and providing specific VPA targets.

FUNDING

None.

Optimal dose and type of physical activity to improve functional capacity and minimise adverse events in acutely hospitalised older adults: a systematic review with dose-response network meta-analysis of randomised controlled trials

OBJECTIVE

To identify the optimal dose and type of physical activity to improve functional capacity and reduce adverse events in acutely hospitalised older adults.

DESIGN

Systematic review and Bayesian model-based network meta-analysis.

DATA SOURCES

Four databases were searched from inception to 20 June 2022.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised controlled trials that assessed the effectiveness of a physical activity-based intervention on at least one functional outcome in people aged ≥50 years hospitalised due to an acute medical condition were included. Pooled effect estimates (ie, standardised mean differences for functional capacity and the ratio of means for adverse events) were calculated using random treatment effects network meta-analysis models.

RESULTS

Nineteen studies (3842 participants) met the inclusion criteria. Approximately 100 Metabolic Equivalents of Task per day (METs-min/day) (~40 min/day of light effort or ~25 min/day of moderate effort activities) was the minimal dose to improve the functional capacity of acute hospitalised older adults (standardised mean difference (SMD)=0.28, 95% credible interval (CrI) 0.01 to 0.55). The optimal dose was estimated at 159 METs-min/day (~70 min/day of light effort or ~40 min/day of moderate effort activities; SMD=0.41, 95% CrI 0.08 to 0.72). Ambulation was deemed the most efficient intervention, and the optimal dose was reached at 143 METs-min/day (~50 min/day of slow-paced walking; SMD=0.76, 95% CrI 0.35 to 1.16), showing a high evidential power (87.68%). The minimal effective ambulation dose was estimated at 74 METs-min/day (~25 min/day of slow-paced walking; SMD=0.25, 95% CrI 0.01 to 0.41). Physical activity interventions resulted in a decrease in the rate of adverse events compared with usual care at discharge (ratio of means=0.96, 95% CrI 0.95 to 0.97; median time 7 days).

CONCLUSIONS

This meta-analysis yielded low to moderate evidence supporting the use of in-hospital supervised physical activity programmes in acutely hospitalised older adults. As little as ~25 min/day of slow-paced walking is sufficient to improve functional capacity and minimise adverse events in this population.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42021271999.

Accelerometer-measured intensity-specific physical activity, genetic risk and incident type 2 diabetes: a prospective cohort study

OBJECTIVE

Although 30 min/day of moderate-intensity physical activity is suggested for preventing type 2 diabetes (T2D), the current recommendations exclusively rely on self-reports and rarely consider the genetic risk. We examined the prospective dose-response relationships between total/intensity-specific physical activity and incident T2D accounting for and stratified by different levels of genetic risk.

METHODS

This prospective cohort study was based on 59 325 participants in the UK Biobank (mean age=61.1 years in 2013-2015). Total/intensity-specific physical activity was collected using accelerometers and linked to national registries until 30 September 2021. We examined the shape of the dose-response association between physical activity and T2D incidence using restricted cubic splines adjusted for and stratified by a polygenic risk score (based on 424 selected single nucleotide polymorphisms) using Cox proportional hazards models.

RESULTS

During a median follow-up of 6.8 years, there was a strong linear dose-response association between moderate-to-vigorous-intensity physical activity (MVPA) and incident T2D, even after adjusting for genetic risk. Compared with the least active participants, the HRs (95% CI) for higher levels of MVPA were: 0.63 (0.53 to 0.75) for 5.3-25.9 min/day, 0.41 (0.34 to 0.51) for 26.0-68.4 min/day and 0.26 (0.18 to 0.38) for >68.4 min/day. While no significant multiplicative interaction between physical activity measures and genetic risk was found, we found a significant additive interaction between MVPA and genetic risk score, suggesting larger absolute risk differences by MVPA levels among those with higher genetic risk.

CONCLUSION

Participation in physical activity, particularly MVPA, should be promoted especially in those with high genetic risk of T2D. There may be no minimal or maximal threshold for the benefits. This finding can inform future guidelines development and interventions to prevent T2D.

Leisure-Time Physical Activity and Risk of Microvascular Complications in Individuals With Type 2 Diabetes: A UK Biobank Study

OBJECTIVE

The aim of this study was to determine dose-response associations, including the minimal effective level, between leisure-time physical activity and risk of incident neuropathy, nephropathy, and retinopathy.

RESEARCH DESIGN AND METHODS

This cohort study included 18,092 individuals with type 2 diabetes from the UK Biobank. Self-reported leisure-time physical activity was converted into MET-hours per week. Participants were categorized into no physical activity (0 MET-h/week), below recommendations (0-7.49 MET-h/week), at recommendations (7.5-14.9 MET-h/week), and above recommendations (≥15 MET-h/week). Microvascular complications were identified from hospital inpatient records using diagnosis codes. We used Cox proportional hazards regression analysis to calculate adjusted hazard ratios (aHRs) and restricted cubic splines to identify the minimal effective level of physical activity.

RESULTS

During a median follow-up of 12.1 years, 672 individuals (3.7%) were diagnosed with neuropathy, 1,839 (10.2%) with nephropathy, and 2,099 (11.7%) with retinopathy. Any level of physical activity was associated with a lower risk of neuropathy and nephropathy but not retinopathy. Compared with those reporting no physical activity, the aHR of neuropathy was 0.71 (95% CI 0.53, 0.90) below recommendations, 0.73 (0.56, 0.96) at recommendations, and 0.67 (0.52, 0.87) above recommendations. Corresponding aHRs for nephropathy were 0.79 (0.68, 0.92), 0.80 (0.67, 0.95), and 0.80 (0.68, 0.95). The association with retinopathy was weaker, with aHRs of 0.91 (0.78, 1.06), 0.91 (0.77, 1.08), and 0.98 (0.84, 1.15), respectively.

CONCLUSIONS

Any level of leisure-time physical activity was associated with a lower risk of neuropathy and nephropathy but not retinopathy in individuals with type 2 diabetes. For both neuropathy and nephropathy, the minimal effective physical activity level may correspond to <1.5 h of walking per week.

Trends in adherence to the muscle-strengthening activity guidelines in the US over a 20-year span

PURPOSE

Purpose to evaluate the prevalence and temporal trends in adherence to muscle-strengthening activity (MSA) guidelines among the US population from 1997 to 2018 (pre-Covid 19).

METHODS

We used nationally representative data from the National Health Interview Survey of the US (NHIS; a cross-sectional household interview survey). We pooled data from 22 consecutive cycles (1997 to 2018) and estimated prevalence and trends of adherence to MSA guidelines among adults aged 18-24 years, 25-34 years, 35-44 years, 45-64 years, and ≥ 65 years.

RESULTS

A total of 651,682 participants (mean age 47.7 years [SD = 18.0], 55.8% women) were included. The overall prevalence of adherence to MSA guidelines significantly increased (p < .001) from 1997 to 2018 (19.8% to 27.2%, respectively). Adherence levels significantly increased (p < .001) for all age groups from 1997 to 2018. Compared with their white non-Hispanic counterparts, the odds ratio for Hispanic females was 0.5 (95% CI = 0.4-0.6).

CONCLUSIONS

It is over a 20-year span, adherence to MSA guidelines increased across all age groups, although the overall prevalence remained below 30%. Future intervention strategies to promote MSA are required with a particular focus on older adults, women, Hispanic women, current smokers, those with low educational levels, and those with functional limitations or chronic conditions.

Socioeconomic position as a predictor of youth's movement trajectory profiles between ages 10 and 14 years

BACKGROUND

Combinations of movement behaviors (i.e., physical activity, sedentary behavior, sleep) are associated with health and developmental outcomes in youth. Youth vary in how they accumulate these behaviors, both in volume and specific domains (e.g., sedentary time spent on recreational screen activities vs homework). The aim of this study was to examine how youth's combined general and domain-specific movement trajectories differ by socioeconomic position.

METHODS

We conducted a longitudinal, group-based multi-trajectory analysis to identify general and domain-specific movement trajectory profiles for 2457 youth from age 10 to 14 years from the Longitudinal Study of Australian Children from 2014-2018. We used multinomial logistic regression to test if socioeconomic position predicted profile membership.

RESULTS

We identified three general movement trajectory profiles for both sexes, four domain-specific profiles for males, and five for females. For general movement trajectories, females from lower socioeconomic positions were more likely to be a combination of less active and more sedentary than females from higher socioeconomic positions. Males across socioeconomic positions spend similar amounts of time in physical activity, sedentary time, and sleep. For domain-specific movement trajectories, youth from lower socioeconomic positions were likely to spend a combination of less time in education-based sedentary behavior and more time in recreational screen activities than their higher socioeconomic position peers.

CONCLUSION

Our results indicate that socioeconomic position predicted in which domains youth accumulate their movements. Future observational research and interventions targeting different socioeconomic groups should therefore consider domain-specific movement trajectories.

Arabic translation and cultural adaptation of sedentary behavior, dietary habits, and preclinical mobility limitation questionnaires: A cognitive interview study

BACKGROUND

Developing global evidence on the influence of health-related behaviors (e.g., sedentary behavior, diet) and mobility limitations on health requires global consortia from diverse sets of countries. Thus, the purpose was to translate and culturally adapt (i) the Sedentary Behavior Questionnaire (SBQ); (ii) the Dietary Habits Questionnaire adapted from the Survey of Health, Aging and Retirement in Europe (SHARE) study; (iii) the Preclinical Mobility Limitation questionnaire for use in the Saudi Arabian context.

METHOD

50 adult Saudi participants (mean age 41.7±9.6, 48% female) participated in this study. We followed a systematic cross-cultural adaptation process that involved forward translation, synthesis, back-translation, expert panel, and pre-testing (cognitive interviewing). Four rounds of cognitive interviews were held with 40 participants for the SBQ, SHARE questionnaire, and the Preclinical Mobility Limitation questionnaire, an additional round was needed for the Preclinical Mobility Limitation questionnaire. Descriptive data (means ± standard deviations and frequencies with percentages) were reported for characteristics.

RESULT

With some minor changes to the questionnaires, the SBQ, Dietary Habits, and Preclinical Mobility Limitation questionnaires were translated and cross-culturally adapted into Arabic. 100% of the participants confirmed that the resulting Arabic versions of the SBQ, Dietary Habits questionnaire, and Preclinical Mobility Limitation questionnaires were appropriate and fully understandable for Arabic speakers in communicating the intended meanings of the items in each. For example, item SBQ1, 'Watching television (including videos on VCR/DVD)' was changed to 'Sitting and watching television or videos (including smartphones, tablets)'.

CONCLUSION

The SBQ, Dietary Habits questionnaire, and Preclinical Mobility Limitation questionnaire were successfully cross-culturally adapted into Arabic and are now ready for use in Saudi Arabian.

Effects of physical exercise on physical function in older adults in residential care: a systematic review and network meta-analysis of randomised controlled trials

BACKGROUND

Physical exercise is effective at attenuating ageing-related physical decline in general, but evidence of its benefits for older adults in residential care, who often have functional dependency, multimorbidity, and polypharmacy, is inconclusive. We aimed to establish the effects of exercise interventions on the physical function of this population.

METHODS

For this systematic review and network meta-analysis, we searched PubMed, Web of Science, Cochrane Library, Rehabilitation & Sports Medicine Source, and SPORTDiscus to identify randomised controlled trials assessing the effects of exercise interventions (vs usual care) on physical function (ie, functional independence, physical performance, and other related measures, such as muscle strength, balance, or flexibility) in adults aged 60 years or older living in residential care. Relevant studies published in English or Spanish up to Jan 12, 2023, were included in the systematic review. The quality of studies was assessed using the Tool for the Assessment of Study Quality and Reporting in Exercise (TESTEX) score. A network meta-analysis was performed for physical function-related outcomes reported in at least ten studies, with subanalyses for specific intervention (ie, exercise type, training volume, and study duration) and participant (eg, having cognitive impairment or dementia, pre-frail or frail status, and being functionally dependent) characteristics. The study protocol was registered on PROSPERO (CRD42021247809).

FINDINGS

147 studies (11 609 participants, with mean ages ranging from 67 years [SD 9] to 92 years [2]) were included in the systematic review, and were rated as having overall good quality (median TESTEX score 9 [range 3-14]). In the meta-analysis (including 105 studies, n=7759 participants), exercise interventions were associated with significantly improved overall physical function, with a standardised mean difference [SMD] of 0·13 (95% credible interval [CrI] 0·04-0·21), which was confirmed in all analysed subpopulations. The strongest association was observed with 110-225 min per week of exercise, and the greatest improvements were observed with 170 min per week (SMD 0·36 [95% CrI 0·20-0·52]). No significant differences were found between exercise types. Subanalyses showed significant improvements for almost all analysed physical function-related outcomes (Barthel index, five-times sit-to-stand test, 30-s sit-to-stand test, knee extension, hand grip strength, bicep curl strength, Short Physical Performance Battery, 6-min walking test, walking speed, Berg balance scale, and sit-and-reach test). Large heterogeneity was found between and within studies in terms of population and intervention characteristics.

INTERPRETATION

Exercise interventions are associated with improved physical function in older adults in residential care, and should, therefore, be routinely promoted in long-term care facilities.

FUNDING

None.

TRANSLATION

For the Spanish translation of the abstract see Supplementary Materials section.

Body composition and mortality from middle to old age: a prospective cohort study from the UK Biobank

BACKGROUND

How the association between adiposity and the risk of death changes with age, and which is the optimal level of adiposity to reduce mortality in older ages, is still not completely understood. We aimed to ascertain the age-specific risks of mortality associated with different measures of adiposity.

METHODS

This was a prospective UK Biobank cohort study. Participants were categorized based on five different adiposity and body composition metrics. We explored the age-varying associations between body composition indices and all-cause mortality from 45 to 85 years of age at follow-up using hazard ratios (HR) from flexible parametric survival models with multivariable adjustment and age as timescale. Participants were followed from baseline (2006-2010) through 31 March 2020.

RESULTS

We included 369,752 participants (mean baseline age = 56.3 ± 8.1 years; range 38.9-73.7 years; 54.1% women) and 10,660 deaths during a median follow-up of 11.4 years. Associations between body mass index and mortality were similar when using the fat mass index in magnitude and shape. Compared to participants with normal weight, overweight was not associated with the risk of death regardless of age and the adiposity measure used. Participants with obesity class I showed an HR of 1.20 (95% confidence interval [CI]: 1.08, 1.33) and 1.14 (95%CI: 0.98, 1.30) at ages 60 and 80, respectively, and participants with obesity class II an HR about 1.55 across all age. More attenuated associations with higher age were found in individuals with the highest obesity using the fat mass index. Very high lean mass was associated with an increased risk of mortality in those aged 55-75 years (HR about 1.20 across all ages).

CONCLUSION

Obesity should be prevented at any age. Attenuated associations with older age were observed only among the individuals with the highest obesity, but the risk remained higher compared to normal-weight participants. Lean mass did not reduce mortality risk at any age.

Reference values for wrist-worn accelerometer physical activity metrics in England children and adolescents

BACKGROUND

Over the last decade use of raw acceleration metrics to assess physical activity has increased. Metrics such as Euclidean Norm Minus One (ENMO), and Mean Amplitude Deviation (MAD) can be used to generate metrics which describe physical activity volume (average acceleration), intensity distribution (intensity gradient), and intensity of the most active periods (MX metrics) of the day. Presently, relatively little comparative data for these metrics exists in youth. To address this need, this study presents age- and sex-specific reference percentile values in England youth and compares physical activity volume and intensity profiles by age and sex.

METHODS

Wrist-worn accelerometer data from 10 studies involving youth aged 5 to 15 y were pooled. Weekday and weekend waking hours were first calculated for youth in school Years (Y) 1&2, Y4&5, Y6&7, and Y8&9 to determine waking hours durations by age-groups and day types. A valid waking hours day was defined as accelerometer wear for ≥ 600 min·d^-1 and participants with ≥ 3 valid weekdays and ≥ 1 valid weekend day were included. Mean ENMO- and MAD-generated average acceleration, intensity gradient, and MX metrics were calculated and summarised as weighted week averages. Sex-specific smoothed percentile curves were generated for each metric using Generalized Additive Models for Location Scale and Shape. Linear mixed models examined age and sex differences.

RESULTS

The analytical sample included 1250 participants. Physical activity peaked between ages 6.5-10.5 y, depending on metric. For all metrics the highest activity levels occurred in less active participants (3^rd-50^th percentile) and girls, 0.5 to 1.5 y earlier than more active peers, and boys, respectively. Irrespective of metric, boys were more active than girls (p < .001) and physical activity was lowest in the Y8&9 group, particularly when compared to the Y1&2 group (p < .001).

CONCLUSIONS

Percentile reference values for average acceleration, intensity gradient, and MX metrics have utility in describing age- and sex-specific values for physical activity volume and intensity in youth. There is a need to generate nationally-representative wrist-acceleration population-referenced norms for these metrics to further facilitate health-related physical activity research and promotion.

Influence of poor sleep on cardiovascular disease-free life expectancy: a multi-resource-based population cohort study

BACKGROUND

The complexity of sleep hinders the formulation of sleep guidelines. Recent studies suggest that different unhealthy sleep characteristics jointly increase the risks for cardiovascular disease (CVD). This study aimed to estimate the differences in CVD-free life expectancy between people with different sleep profiles.

METHODS

We included 308,683 middle-aged adults from the UK Biobank among whom 140,181 had primary care data linkage. We used an established composite sleep score comprising self-reported chronotype, duration, insomnia complaints, snoring, and daytime sleepiness to derive three sleep categories: poor, intermediate, and healthy. We also identified three clinical sleep disorders captured by primary care and inpatient records within 2 years before enrollment in the cohort: insomnia, sleep-related breathing disorders, and other sleep disorders. We estimated sex-specific CVD-free life expectancy with three-state Markov models conditioning on survival at age 40 across different sleep profiles and clinical disorders.

RESULTS

We observed a gradual loss in CVD-free life expectancy toward poor sleep such as, compared with healthy sleepers, poor sleepers lost 1.80 [95% CI 0.96-2.75] and 2.31 [1.46-3.29] CVD-free years in females and males, respectively, while intermediate sleepers lost 0.48 [0.41-0.55] and 0.55 [0.49-0.61] years. Among men, those with clinical insomnia or sleep-related breathing disorders lost CVD-free life by 3.84 [0.61-8.59] or 6.73 [5.31-8.48] years, respectively. Among women, sleep-related breathing disorders or other sleep disorders were associated with 7.32 [5.33-10.34] or 1.43 [0.20-3.29] years lost, respectively.

CONCLUSIONS

Both self-reported and doctor-diagnosed poor sleep are negatively associated with CVD-free life, especially pronounced in participants with sleep-related breathing disorders.

Association of occupational physical activity and disability pension in 756,159 Spanish workers: A prospective cohort study with 13 years follow-up

Recent research from Nordic countries identified occupational physical activity (OPA) as a risk factor for disability pension, but further research accounting for exhaustive analyses in novel populations is warranted. Our objective was to assess the association between OPA and disability pension using administrative data. This prospective registry-based cohort study used data from the Spanish Continuous Working Life Sample (CWLS). Participants were followed up from baseline (January 1, 2006) to first event of disability pension, mortality, or end of follow-up (September 1, 2019). The assessment of OPA was based on registers of economic activity and their correspondence with a validated OPA index. To examine the association between OPA and disability pension, adjusted proportional hazard, and Fine-Gray models using mortality as competing risk were conducted. We retrieved data from 756,159 workers (57.7% men) with an average age of 38.5 years (SD 11.9). During 13.6 years from baseline to the end of follow-up (9,463,041 person-years), 18,191 men (4.2%) and 9631 (3.0%) women received a disability pension. In the fully adjusted model, participants exposed to higher levels of OPA showed higher risk for disability pension in an exposure-response fashion. Men and women exposed to very high OPA showed the highest HR for disability pension (2.31 [95% CI, 2.17 to 2.46] and 1.68 [95% CI, 1.56 to 1.81], respectively. These results warrant preventative measures to address early involuntary exit from the labour market in workers exposed to high physical work demands.

High Fragmented Physical Activity as an Early Risk Indicator of Frailty and Mortality in Adults Aged 50 Years and Over

INTRODUCTION

This study aimed to explore the associations of activity fragmentation with frailty status and all-cause mortality in a representative US sample of people 50 years and over.

METHODS

This prospective study used data from the 2003-2006 waves of the National Health and Nutrition Examination Survey (NHANES). Participants 50 years or over were included in the study (n = 2,586). Frailty status was assessed using a valid modification of the Fried criteria. Linked data from the National Death Index registry were used to ascertain mortality. Physical activity fragmentation was measured by accelerometry. To calculate activity fragmentation, an active-to-sedentary transition probability was calculated as the number of physical activity bouts divided by the total sum of minutes spent in physical activity. Age, gender, ethnicity, education, mobility issues, drinking status, smoking status, BMI, and self-reported chronic diseases were reported in the NHANES study.

RESULTS

An increment of 1 SD in activity fragmentation was associated with an increased likelihood of frailty (odds ratio [95% confidence interval] = 1.36 [1.13-1.664]). Compared with participants in the high activity fragmentation/low physical activity category, participants in the low activity fragmentation/low physical activity and low activity fragmentation/high physical activity categories were associated with a lower likelihood of frailty. We found a nonlinear association between activity fragmentation and all-cause mortality. Compared with participants in the high activity fragmentation/low physical activity category, participants in the low activity fragmentation/low physical activity, low activity fragmentation/high physical activity, and high activity fragmentation/high physical activity categories were associated with a lower mortality risk. Participants with a low fragmented activity pattern may also overcome some of the detrimental effects associated with sedentary behavior.

CONCLUSIONS

Our results suggest that a high fragmented physical activity pattern is associated with frailty and risk of mortality in adults and older adults. This association was independent of total volume of physical activity and time spent sedentary.

Associations between Hospitalization and Device-Assessed Physical Activity in a Representative Sample of Older Adults

BACKGROUND

Evidence investigating associations between hospitalization and physical activity is scarce and limited to specific populations of older adults.

OBJECTIVE

The current study aimed to describe the impact of past hospitalization on current physical activity levels of a large representative sample of European older adults with accelerometry data.

METHODS

A representative sample of 856 European older adults aged 50 years and over was included in this study. Hospital admission and utilization (i.e., accumulated times and length of stay in hospital) in the last 12 months were self-reported retrospectively. Physical activity volume (mg) and distribution of intensity (intensity gradient) were assessed with thigh-worn accelerometers.

RESULTS

Multivariate linear regressions indicated that hospital admission (15% of the sample) was associated with reduced physical activity volume (-4.29 mg; 95% confidence interval (95% CI), -9.07 to 0.47) of participants. Each additional hospital admission was associated with lower volume (-2.29 mg; 95% CI, -4.65 to 0.06) and poorer distribution of intensity (-0.07; 95% CI, -0.11 to -0.04). Total length of stay was not associated with physical activity.

CONCLUSIONS

This study suggests that hospital admission and the number of times admitted, but not accumulated length of stay, may curb physical activity levels of older adults. Public health strategies to promote successful aging should target post-hospitalization physical activity.

Thresholds of handgrip strength for all-cause, cancer, and cardiovascular mortality: A systematic review with dose-response meta-analysis

BACKGROUND

While handgrip strength is associated with all-cause and cause-specific mortality, whether such associations are dose-dependent is largely unknown. Therefore, we conducted a systematic review on the dose-response relationship of handgrip strength with all-cause mortality, cancer, and cardiovascular mortality.

METHODS

The data source included three electronic databases (PubMed/MEDLINE, Web of Science and Scopus) from inception to 8 February 2022. Prospective cohort studies of healthy adults with objective measures of handgrip strength were included. Two researchers independently screened studies, extracted data, and assessed risk of bias. We used estimates regarding handgrip strength categories to conduct a random forest model, and a two-stage random-effects hierarchical meta-regression model pooling study-specific estimates for dose-response relationship. Outcomes included all-cause, cancer, and cardiovascular mortality.

REULTS

Forty-eight studies comprising 3,135,473 participants (49.6% women, age range 35-85 years) were included. Random forest models showed a significant inverse association between handgrip strength and all-cause and cause-specific mortality. Dose-response meta-analyses showed that higher levels of handgrip strength significantly reduced the risk of all-cause mortality within 26-50 kg (Higgin´s I² =45.7%) in a close-to-linear inverse fashion. Cancer and cardiovascular mortality displayed a trend towards a U-shaped association with a significant risk reduction between 16 and 33 kg (Higgin´s I² =77.4%), and a close-to-linear inverse shaped and significant risk reduction ranging from 24 to 40 kg (Higgin´s I² =79.7%) respectively.

CONCLUSION

There is strong evidence for an association between lower handgrip strength with higher all-cause, cancer, and cardiovascular mortality risk. The dose-response relationship of handgrip strength substantially varies depending on the cause of mortality.

Prospective Associations of Daily Step Counts and Intensity With Cancer and Cardiovascular Disease Incidence and Mortality and All-Cause Mortality

IMPORTANCE

Recommendations for the number of steps per day may be easier to enact for some people than the current time- and intensity-based physical activity guidelines, but the evidence to support steps-based goals is limited.

OBJECTIVE

To describe the associations of step count and intensity with all-cause mortality and cancer and cardiovascular disease (CVD) incidence and mortality.

DESIGN, SETTING, AND PARTICIPANTS

This population-based prospective cohort study used data from the UK Biobank for 2013 to 2015 (median follow-up, 7 years) and included adults 40 to 79 years old in England, Scotland, and Wales. Participants were invited by email to partake in an accelerometer study. Registry-based morbidity and mortality were ascertained through October 2021. Data analyses were performed during March 2022.

EXPOSURES

Baseline wrist accelerometer-measured daily step count and established cadence-based step intensity measures (steps/min): incidental steps, (<40 steps/min), purposeful steps (≥40 steps/min); and peak-30 cadence (average steps/min for the 30 highest, but not necessarily consecutive, min/d).

MAIN OUTCOMES AND MEASURES

All-cause mortality and primary and secondary CVD or cancer mortality and incidence diagnosis. For cancer, analyses were restricted to a composite cancer outcome of 13 sites that have a known association with reduced physical activity. Cox restricted cubic spline regression models were used to assess the dose-response associations. The linear mean rate of change (MRC) in the log-relative hazard ratio for each outcome per 2000 daily step increments were also estimated.

RESULTS

The study population of 78 500 individuals (mean [SD] age, 61 [8] years; 43 418 [55%] females; 75 874 [97%] White individuals) was followed for a median of 7 years during which 1325 participants died of cancer and 664 of CVD (total deaths 2179). There were 10 245 incident CVD events and 2813 cancer incident events during the observation period. More daily steps were associated with a lower risk of all-cause (MRC, -0.08; 95% CI, -0.11 to -0.06), CVD (MRC, -0.10; 95% CI, -0.15 to -0.06), and cancer mortality (MRC, 95% CI, -0.11; -0.15 to -0.06) for up to approximately 10 000 steps. Similarly, accruing more daily steps was associated with lower incident disease. Peak-30 cadence was consistently associated with lower risks across all outcomes, beyond the benefit of total daily steps.

CONCLUSIONS AND RELEVANCE

The findings of this population-based prospective cohort study of 78 500 individuals suggest that up to 10 000 steps per day may be associated with a lower risk of mortality and cancer and CVD incidence. Steps performed at a higher cadence may be associated with additional risk reduction, particularly for incident disease.

Longitudinal association of handgrip strength with all-cause and cardiovascular mortality in older adults using a causal framework

To date, there is no study addressing the time-varying confounding bias in the association of handgrip strength (HGS) with all-cause or cardiovascular mortality. Therefore, we conducted marginal structural models (MSM) to provide causal estimations on the associations of HGS with all-cause and cardiovascular mortality in a representative sample of adults aged 50 years or older. Data from 29 countries including 121,116 participants (276,994 observations; mean age 63.7 years; 56.3 % women) free from prior heart attack or stroke were retrieved from consecutive waves of the Survey of Health, Ageing and Retirement in Europe (SHARE). During a median of 7.7 years follow-up (interquartile range 3.8-11.8) and 1,009,862 person-years, 6407 participants (5.3 %) died due to all causes, and 2263 (1.9 %) died due to cardiovascular diseases. Using repeated measures of handheld dynamometry, we determined absolute and relative to body mass index HGS of each participant. We applied adjusted MSM to estimate hazard ratios (HRs) associated with changes over time in HGS addressing the time-varying confounding bias. An increase of 5 kg in HGS was associated with a reduced risk of all-cause [HR 0.86, 95 % confidence interval (CI), 0.86-0.90], overall cardiovascular (HR 0.86, 95 % CI 0.82-0.86), heart attack (HR 0.90, 95 % CI 0.86-0.95), and stroke (HR 0.86, 95 % CI 0.82-0.90) mortality. The associations of relative HGS were of stronger magnitude in all cases. Our findings provide critical evidence on the importance of increasing general muscle strength in older adults to reduce mortality risk, particularly concerning cardiovascular causes.

Physical activity phenotypes and mortality in older adults: a novel distributional data analysis of accelerometry in the NHANES

Physical activity is deemed critical to successful ageing. Despite evidence and progress, there is still a need to determine more precisely the direction, magnitude, intensity, and volume of physical activity that should be performed on a daily basis to effectively promote the health of individuals. This study aimed to assess the clinical validity of new physical activity phenotypes derived from a novel distributional functional analysis of accelerometer data in older adults. A random sample of participants aged between 65 and 80 years with valid accelerometer data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014 was used. Five major clinical phenotypes were identified, which provided a greater sensitivity for predicting 5-year mortality and survival outcomes than age alone, and our results confirm the importance of moderate-to-vigorous physical activity. The new clinical physical activity phenotypes are a promising tool for improving patient prognosis and for directing to more targeted intervention planning, according to the principles of precision medicine. The use of distributional representations shows clear advantages over more traditional metrics to explore the effects of the full spectrum of the physical activity continuum on human health.

Association of Daily Step Count and Intensity With Incident Dementia in 78 430 Adults Living in the UK

Importance

Step-based recommendations may be appropriate for dementia-prevention guidelines. However, the association of step count and intensity with dementia incidence is unknown.

Objective

To examine the dose-response association between daily step count and intensity and incidence of all-cause dementia among adults in the UK.

Design, Setting, and Participants

UK Biobank prospective population-based cohort study (February 2013 to December 2015) with 6.9 years of follow-up (data analysis conducted May 2022). A total of 78 430 of 103 684 eligible adults aged 40 to 79 years with valid wrist accelerometer data were included. Registry-based dementia was ascertained through October 2021.

Exposures

Accelerometer-derived daily step count, incidental steps (less than 40 steps per minute), purposeful steps (40 steps per minute or more), and peak 30-minute cadence (ie, mean steps per minute recorded for the 30 highest, not necessarily consecutive, minutes in a day).

Main Outcomes and Measures

Incident dementia (fatal and nonfatal), obtained through linkage with inpatient hospitalization or primary care records or recorded as the underlying or contributory cause of death in death registers. Spline Cox regressions were used to assess dose-response associations.

Results

The study monitored 78 430 adults (mean [SD] age, 61.1 [7.9] years; 35 040 [44.7%] male and 43 390 [55.3%] female; 881 [1.1%] were Asian, 641 [0.8%] were Black, 427 [0.5%] were of mixed race, 75 852 [96.7%] were White, and 629 [0.8%] were of another, unspecified race) over a median (IQR) follow-up of 6.9 (6.4-7.5) years, 866 of whom developed dementia (mean [SD] age, 68.3 [5.6] years; 480 [55.4%] male and 386 [54.6%] female; 5 [0.6%] Asian, 6 [0.7%] Black, 4 [0.4%] mixed race, 821 [97.6%] White, and 6 [0.7%] other). Analyses revealed nonlinear associations between daily steps. The optimal dose (ie, exposure value at which the maximum risk reduction was observed) was 9826 steps (hazard ratio [HR], 0.49; 95% CI, 0.39-0.62) and the minimal dose (ie, exposure value at which the risk reduction was 50% of the observed maximum risk reduction) was 3826 steps (HR, 0.75; 95% CI, 0.67-0.83). The incidental cadence optimal dose was 3677 steps (HR, 0.58; 95% CI, 0.44-0.72); purposeful cadence optimal dose was 6315 steps (HR, 0.43; 95% CI, 0.32-0.58); and peak 30-minute cadence optimal dose was 112 steps per minute (HR, 0.38; 95% CI, 0.24-0.60).

Conclusions and Relevance

In this cohort study, a higher number of steps was associated with lower risk of all-cause dementia. The findings suggest that a dose of just under 10 000 steps per day may be optimally associated with a lower risk of dementia. Steps performed at higher intensity resulted in stronger associations.

Association of accelerometer-derived step volume and intensity with hospitalizations and mortality in older adults: A prospective cohort study

PURPOSE

This study aimed to examine the associations of accelerometer-derived steps volume and intensity with hospitalizations and all-cause mortality in older adults.

METHODS

This prospective cohort study involved 768 community-dwelling Spanish older adults (78.8 ± 4.9 years, mean ± SD; 53.9% females) from the Toledo Study for Healthy Aging (2012-2017). The number of steps per day and step cadence (steps/min) were derived from a hip-mounted accelerometer worn for at least 4 days at baseline. Participants were followed-up over a mean period of 3.1 years for hospitalization and 5.7 years for all-cause mortality. Cox proportional hazards regression models were used to estimate the individual and joint associations between daily steps and stepping intensity with hospitalizations and all-cause mortality.

RESULTS

Included participants walked 5835 ± 3445 steps/day with an intensity of 7.3 ± 4.1 steps/min. After adjusting for age, sex, body mass index (BMI), education, income, marital status and comorbidities, higher step count (hazard ratio (HR) = 0.95, 95% confidence interval (95%CI: 0.90-1.00, and HR = 0.87, 95%CI: 0.81-0.95 per additional 1000 steps) and higher step intensity (HR = 0.95, 95%CI: 0.91-0.99, and HR = 0.89, 95%CI: 0.84-0.95 per each additional step/min) were associated with fewer hospitalizations and all-cause mortality risk, respectively. Compared to the group having low step volume and intensity, individuals in the group having high step volume and intensity had a lower risk of hospitalization (HR = 0.72, 95%CI: 0.52-0.98) and all-cause mortality (HR = 0.60, 95%CI: 0.37-0.98).

CONCLUSION

Among older adults, both high step volume and step intensity were significantly associated with lower hospitalization and all-cause mortality risk. Increasing step volume and intensity may benefit older people.

Optimal Number of Steps per Day to Prevent All-Cause Mortality in People With Prediabetes and Diabetes

OBJECTIVE

We aimed to examine the dose-response associations between the number of steps per day and all-cause mortality among adults with prediabetes and diabetes.

RESEARCH DESIGN AND METHODS

This prospective study used data from 1,194 U.S. adults with prediabetes and 493 with diabetes for whom accelerometer-derived steps per day could be retrieved. Mortality was ascertained through the National Death Index (February 25, 2019). Splines were used to assess the dose-response associations between steps per day and all-cause mortality.

RESULTS

Over ∼9 years of follow-up, 200 adults with prediabetes and 138 with diabetes died. Nonlinear associations akin to an L shape were observed. We estimated an optimal dose of ∼10,000 steps per day to reduce the risk of all-cause mortality for both individuals with prediabetes and those with diabetes.

CONCLUSIONS

Accumulating more steps per day up to ∼10,000 steps per day may lower the risk of all-cause mortality of adults with prediabetes and diabetes.

Community-based exercise enhanced by a self-management programme to promote independent living in older adults: a pragmatic randomised controlled trial

BACKGROUND

older adults face several modifiable barriers for engaging in physical activity (PA) programmes such as incontinence, loneliness and fear of falling. Enhancing PA programmes with behavioural components to support self-management of such barriers may increase the effectiveness to preserve functional capacity and independent living.

OBJECTIVE

this study aimed at assessing the effects of a complex active lifestyle intervention (CALSTI) on objective and self-report measures of functional capacity and disability in community-dwelling older adults.

SUBJECTS AND METHODS

about 215 older adults (79.9 ± 0.4 years) at increased risk of functional decline were randomly allocated to (i) CALSTI consisting of 12-weeks progressive explosive resistance training (24 sessions) enhanced by a 24-week multi-factorial self-management programme (8 sessions), or (ii) an extended version of the self-management intervention (SEMAI; 12 sessions) to reflect a reinforcement of usual care. The interventions were embedded in a nationally regulated preventive care pathway. Blinded assessors collected primary (the Short Physical Performance Battery; SPPB) and secondary outcome data (self-reported difficulty in activities of daily living, the short version of the Late-Life Function and Disability Index, and the EQ-health VAS scale) at baseline and after 12 and 24 weeks.

RESULTS

after 24 weeks, CALSTI led to a clinically superior increase in SPPB compared with SEMAI (+0.77 points, P < 0.01), and the CALSTI group also demonstrated improvements in selected self-reported outcomes.

CONCLUSIONS

a novel complex exercise and multi-factorial self-management intervention embedded in preventive care practice had large and clinically meaningful effects on a key measure of functional capacity and predictor of disability.

Occupational physical activity trends from 1987 to 2017: A nationally representative sample of 160,509 Spanish adults

AIMS

To estimate temporal and updated trends of OPA among Spanish adult population during the period between 1987 and 2017.

METHODS

We used all available rounds of the Spanish National Health Survey (160,509 adults, mean age 44.6 years [SD 16.6], 50.3% women) and multivariate regressions to determine temporal trends of high OPA from 1987 to 2017 in the general working population of Spain.

RESULTS

The highest OPA prevalence was observed for participants aged 31-49 years in the 2003 survey. The prevalence of high OPA was generally low, but increased slightly over time in the 18-30, 50-64, and 65-75 years old (p<0.001 for trend). In contrast, a general reduction in OPA was observed in the 16-17 years old (p<0.001 for trend). Men consistently showed higher OPA prevalence than women.

CONCLUSIONS

This study reports an increase in OPA prevalence in Spain from 1987 to 2017, which is low and significant in most socio-demographic groups, but small in absolute terms. The youngest group had a marked decreased in OPA prevalence over the course of the study. Men consistently showed higher OPA prevalence than women, but differences have become smaller in recent years. Our results may assist in the establishment of interventional strategies and future policies among specific subgroups.Highlights: There is an increase in OPA prevalence in Spain from 1987 to 2017.The youngest group had a marked decreased in OPA prevalence over the course of the study.Men consistently showed higher OPA prevalence than women, but differences have become smaller in recent years.Frequent national surveillance of OPA to monitor long-term development of the working environment should be mandatory.

Impact on adolescent mental health of replacing screen-use with exercise: A prospective cohort study

BACKGROUND

Screen-based device use could increase the risk of adolescent depression. Distinct modalities of screen-use may have differential effects on mental health. We used compositional data analysis to examine how theoretically replacing different screen-uses with exercise might influence future adolescent emotional distress.

METHODS

In 4,599 adolescents (55% female) from a nationally-representative, prospective cohort, we used time-use diary data at age 14 to estimate daily screen use (television, social media, video game, general computer use) and exercise (team sport and individual exercise). The outcome was emotional distress at age 17, assessed using the emotional symptoms subscale of the Strengths and Difficulties Questionnaire.

RESULTS

Theoretically replacing 60 min of total screen time with exercise at age 14 was associated with a 0.05 (95%CI -0.08, -0.02) score reduction on the emotional symptoms' subscale at 17 in fully-adjusted models. Replacing 60 min of television or social media use with team sports was associated with a reduction of 0.17 (95%CI, -0.31, -0.04) and 0.15 (95%CI, -0.29, -0.01) in emotional symptom scores, respectively. We found no change in emotional symptom scores when replacing video game or general computer use with team sport, or when replacing any screen time with individual exercise.

LIMITATIONS

No direct measure of depressive symptoms at follow-up.

CONCLUSIONS

Replacing any screen time with exercise could reduce emotional distress, but the largest effect sizes were associated with replacing time in television watching and social media with team sports. Recommendations to limit screen-use in adolescents may require a nuanced approach for protecting mental health.

Prospective Associations of Accelerometer-Assessed Physical Activity With Mortality and Incidence of Cardiovascular Disease Among Adults With Hypertension: The UK Biobank Study

Background Despite the well-established capacity of physical activity to reduce blood pressure, the associations between physical activity with cardiovascular disease (CVD) incidence and mortality in people living with hypertension are not well understood. We examine the dose-response associations of device-assessed physical activity with all-cause and CVD mortality and CVD incidence (total, stroke, and coronary heart disease) in adults with hypertension. Methods and Results This prospective study included data from 39 294 participants with hypertension in the UK Biobank study who had valid accelerometry data and for whom mortality and CVD followed-up data were available. We categorized moderate-to-vigorous physical activity and total physical activity volume into 4 categories based on the 10th, 50th, and 90th percentiles and used Cox regressions to estimate their associations with CVD mortality and incidence outcomes. Splines were used to assess the dose-response associations. During a median follow-up of 6.25 years (241 418 person-years), 1518 deaths (549 attributable to CVD) and 4933 CVD (fatal and nonfatal) incident events were registered. Compared with the lowest category of moderate-to-vigorous physical activity, the relative risks (hazard ratios and 95% CIs) of all-cause mortality for increasing categories were 0.53 (0.46-0.61), 0.41 (0.34-0.49), and 0.36 (0.26-0.49). We found associations of similar magnitude for total CVD incidence, stroke, and coronary heart disease; and for total physical activity volume across all outcomes. For all outcomes, there were linear or nearly linear inverse dose-response relationships with no evidence of harms with high levels of physical activity. Results were robust to removing participants who died within the first 2 years. Conclusions Our findings underscore the importance of physical activity for people living with hypertension and provide novel insights to support the development of physical activity guideline recommendations for this high-risk group.

Accuracy of different cutoffs of the waist-to-height ratio as a screening tool for cardiometabolic risk in children and adolescents: A systematic review and meta-analysis of diagnostic test accuracy studies

The present systematic review with meta-analysis sought to estimate the accuracy of different waist-to-height ratio (WHtR) cutoff ranges as risk indicators for cardiometabolic health in different populations of children and adolescents. Systematic searches were undertaken to identify studies in apparently healthy participants aged 3-18 years that conducted receiver operating characteristic curve analysis and reported area under the receiver operating characteristic curves for WHtR with any cardiometabolic biomarker. Forty-one cross-sectional studies were included in the meta-analysis, including 138,561 young individuals (50% girls). Higher area under summary receiver operating characteristic (AUSROC) values were observed in cutoffs between 0.46 and 0.50 (AUSROC = 0.83, 95%CI: 0.80-0.86) and ≥0.51 (AUSROC = 0.87, 95%CI: 0.84-0.90) (p < 0.001 in comparison with cutoffs 0.41 to 0.45), with similar results in both sexes. The AUSROC value increased in the East and Southeast Asian regions using a WHtR cutoff of ≥0.46 (AUSROC = 0.90, 95%CI: 0.87 to 0.92). A cutoff of ≥0.54 was optimal for the Latin American region (AUSROC = 0.96, 95%CI: 0.94-0.97). Our meta-analysis identified optimal cutoff values of WHtR for use in children and adolescents from different regions. Despite the widely accepted WHtR cutoff of 0.50, the present study indicated that a single cutoff value of WHtR may be inappropriate.

Can Physical Activity Make Up for the Self-Care Disability Effects of Too Much Sitting? A Moderation Analysis in Octogenarians Residing in Living Care Facilities

BACKGROUND AND PURPOSE

Physical activity can delay the progression of self-care disability in older adults residing in living care facilities. Nonetheless, older adults residing in living care facilities spend most of their time sedentary and do not meet the physical activity recommendation, which may result in increasing self-care disability in this population group. In this study, we aimed to determine whether the association between sedentary time and self-care disability was moderated by moderate-to-vigorous physical activity (MVPA) in older adults residing in living care facilities.

METHODS

Sedentary time and MVPA were both measured with accelerometers. Self-care disability was assessed with the Barthel Index. A multivariate regression model was used to ascertain the effects of the interaction between sedentary time and MVPA on the self-care disability of participants. The Johnson-Neyman technique was then used to estimate the exact MVPA threshold at which the effect of sedentary time on self-care disability became nonsignificant.

RESULTS

We found a significant effect of sedentary time on self-care disability (standardized β=-1.66; 95% CI -1.77 to -1.54, P = .013). Results indicated that MVPA moderates the relationship between self-care disability status and sedentary time (standardized β= 1.14; 95% CI 1.13 to 1.14, P = .032). The Johnson-Neyman technique determined that 51 min/day of MVPA would offset the negative effects of sedentary time on self-care disability.

CONCLUSIONS

Our results suggest physical therapists should focus on reducing sedentary time alongside physical activity to prevent the progression to dependency in octogenarians residing in living care facilities.

Light-Intensity Physical Activity and Life Expectancy: National Health and Nutrition Survey

INTRODUCTION

Quantifying the years of life gained associated with light-intensity physical activity may be important for risk communication in public health. Because no studies have examined the role of light-intensity physical activity in life expectancy, this study aims to quantify the years of life gained from light-intensity physical activity in a population-based U.S.

METHODS

This study used data from 6,636 participants in the National Health and Nutrition Examination Survey (2003-2006). Analyses were conducted in 2020. Light-intensity physical activity was categorized into low, medium, and high on the basis of tertiles, and survival models were applied to estimate the years of life gained from each light-intensity physical activity group. Analyses were repeated in participants with moderate-to-vigorous physical activity above or below the median.

RESULTS

During a mean follow-up of 11 years and at 55,520 person-years, 994 deaths were recorded. At age 20 years, participants with low, medium, and high light-intensity physical activity had a predicted life expectancy of 53.92 (95% CI=46.66, 61.18), 58.16 (95% CI=52.10, 65.22), and 58.44 (95% CI=51.29, 65.60) years, suggesting significant years of life gained from medium and high levels of light-intensity physical activity of 2.89 (95% CI=0.90, 4.12) and 3.07 (95% CI=0.84, 5.30) years. The corresponding years of life gained at age 45 years and 65 years were 2.51 (95% CI=0.40, 5.47) and 1.52 (95% CI=0.54, 2.50) years for the medium light-intensity physical activity group and 2.66 (95% CI=0.80, 4.52) and 1.62 (95% CI=0.49, 52.75) years for the high light-intensity physical activity group. This association was significant in participants with moderate-to-vigorous physical activity below the median but not for those with moderate-to-vigorous physical activity above the median.

CONCLUSIONS

Light-intensity physical activity may extend life expectancy. Given the low prevalence of moderate-to-vigorous physical activity in populations, physical activity promotion efforts may capitalize on emerging evidence on light-intensity physical activity, particularly among the most inactive groups.

Associations Between Movement Behaviors and Emotional Changes in Toddlers and Preschoolers During Early Stages of the COVID-19 Pandemic in Chile

Background: There is limited evidence about emotional and behavioral responses in toddlers and preschoolers during the novel coronavirus (COVID-19) pandemic, particularly in Latin America. Objective: To assess associations between changes in movement behaviors (physical activity, screen time and sleeping) and emotional changes in toddlers and preschoolers during early stages of the pandemic in Chile. Methods: A cross-sectional study conducted from March 30th to April 27th, 2020. Main caregivers of 1- to 5-year-old children living in Chile answered an online survey that included questions about sociodemographic characteristics, changes in the child's emotions and behaviors, movement behaviors and caregivers' stress during the pandemic. Multiple linear regressions were used to assess the association between different factors and emotional changes in toddlers and preschoolers. Results: In total, 1727 caregivers provided complete data on emotional changes for children aged 2.9 ± 1.36 years old, 47.9% girls. A large proportion of toddlers and preschoolers in Chile experienced emotional and behavioral changes. Most caregivers reported that children "were more affectionate" (78.9%), "more restless" (65.1%), and 'more frustrated' (54.1%) compared with pre-pandemic times. Apart from changes in movement behaviors, factors such as child age, caregivers' age and stress, and residential area (urban/rural) were consistently associated with changes in emotions and behaviors. Conclusion: The pandemic substantially affected the emotions and behaviors of toddlers and preschoolers in Chile. The findings suggest that supportive actions for caregivers may have a positive impact not only on adults but also on children. Mental health promotion programs should consider multilevel approaches in which the promotion of movement behaviors and support for caregivers should be essential pieces for future responses.

Impact of Social Isolation on Physical Functioning Among Older Adults: A 9-Year Longitudinal Study of a U.S.-Representative Sample

INTRODUCTION

Social isolation among older adults is associated with poor health and premature mortality, but its impact on physical functioning is not fully understood. Previous studies have typically relied on community samples, cross-sectional data, and suboptimal prospective designs. This study generates more robust evidence by investigating the longitudinal associations between social isolation and physical functioning in a large panel of older adults.

METHODS

Analyses were based on 9 waves of data (2011-2019) from a sample of adults aged ≥65 years from the U.S. National Health and Aging Trends Study (N=12,427 individuals; 54,860 person-year observations) and within-individual fixed-effect panel regression models. Analyses were conducted in 2020. Social isolation was measured using the Social Isolation Index, and physical functioning was measured through the Short Physical Performance Battery.

RESULTS

In fully adjusted fixed-effect regression models, each 1-unit increase in the Social Isolation Index resulted in an average decrease of 0.27 units in the Short Physical Performance Battery (95% CI= -0.31, -0.24). This relationship was moderated by age, with the Social Isolation Index bearing a significantly and substantially stronger influence on the Short Physical Performance Battery at older ages than at younger ages.

CONCLUSIONS

This study confirms that social isolation is associated with deficits in physical functioning among older adults in the U.S. using more robust data and methods than earlier studies. These findings highlight the importance of incorporating strategies to reduce social isolation in policies aimed at promoting successful aging.