Analysis of sedentary behaviour levels and patterns in adults with Down syndrome.

BACKGROUND: Sedentary behaviour (SB) among adults with Down syndrome (DS) may differ based on personal or environmental factors. OBJECTIVE: Investigate differences in SB levels and patterns of adults with DS based on sex, age, and residence-type across weekdays and weekends. METHODS: Thirty-four adults with DS (15 men; 37 ± 12 years) underwent accelerometry-based measurements of sedentary time, bouts, and breaks for 7 days. We evaluated differences with 2 × 2 mixed-model (group-by-day) ANOVA. RESULTS: Younger (19-36 years) individuals had less sedentary time (p = .042), and shorter (p = .048) and fewer (p = .012) bouts than older (37-60 years) individuals. Group home residents had more bouts on weekends than adults living with parent/guardians (p = .015). CONCLUSIONS: Adults with DS spent half their waking hours in SB of short bouts. Age and residence may influence SB.

Physical activity and arterial stiffness: is body fat a mediator?

PURPOSE: Physical activity (PA) and body fat percentage (%BF) are independently associated with arterial stiffness, but it has not been explored if there is an associative pathway among these variables. This study examined whether %BF mediates the relationship between PA or sedentary behavior levels with arterial stiffness. METHODS: Fifty adults (1:1 men:women; age 28 ± 11 year) had carotid-femoral pulse wave velocity (CF-PWV) measured by applanation tonometry, %BF by bioelectrical impedance, and PA levels by accelerometry. Accelerometer data determined minutes per day spent in sedentary, light, moderate-to-vigorous physical activity (MVPA), and Total PA. RESULTS: Pearson correlation indicated statistically significant associations among age, %BF, CF-PWV, MVPA, and Total PA (r = 0.34-0.65, p < 0.05). Sedentary and light PA were not associated with CF-PWV. Mediation analysis indicated significant total effects of MVPA (ß = - 0.34, p = 0.044) and age (ß = 0.65, p < 0.001) on CF-PWV. %BF mediated the relationship between Total PA and CF-PWV due to indirect effect of Total PA on %BF (ß = - 0.34, p = 0.02) and %BF on CF-PWV (ß = 0.44, p = 0.002), and partially mediated the relationship between age and CF-PWV (ß = 0.54, p < 0.001). Total PA retained its significant effect on %BF (ß = - 0.28, p = 0.04) and the effect of %BF on CF-PWV remained significant (ß = 0.26, p = 0.03), despite age having a significant effect on both %BF (ß = 0.31, p = 0.023) and CF-PWV (ß = 0.54, p < 0.001). CONCLUSIONS: %BF mediated the relationship between Total PA and arterial stiffness, even after accounting for age. Engagement in more Total PA may help to reduce %BF, resulting in decreased arterial stiffness.

Health Outcomes of Physical Activity Interventions in Adults With Down Syndrome: A Systematic Review.

This systematic review examined whether physical activity interventions improve health outcomes in adults with Down syndrome (DS). We searched PubMed, APA PsycInfo, SPORTDiscus, APA PsycARTICLES, and Psychology and Behavioral Sciences Collection using keywords related to DS and physical activity. We included 35 studies published in English since January 1, 1990. Modes of exercise training programs included aerobic exercise, strength training, combined aerobic and strength training, aquatic, sport and gaming, and aerobic and strength exercise interventions combined with health education. The evidence base indicates that aerobic and strength exercise training improve physical fitness variables including maximal oxygen uptake, maximal heart rate, upper and lower body strength, body weight, and body fat percentage. Sport and gaming interventions improve functional mobility, work task performance, and sport skill performance. We concluded that adults with DS can accrue health benefits from properly designed physical activity and exercise interventions.

Factors That Influence Physical Activity in Individuals With Down Syndrome: Perspectives of Guardians and Health Professionals.

Identifying factors that influence physical activity (PA) among individuals with Down syndrome is essential for PA promotion. Insight can be gained from guardians and health professionals. The purpose of this study was to explore the perspectives of guardians and health professionals on facilitators and barriers of PA in individuals with Down syndrome. Interviews were conducted with 11 guardians (five mothers, four fathers, and two legal guardians) and 11 professionals (four PA specialists, three physical therapists, and four occupational therapists). Grounded theory was applied. Barriers and facilitators fit the levels of the ecological model of health behavior: (a) intrapersonal (perceived rewards), (b) interpersonal (interaction), (c) community (availability of programs), (d) organizational (school systems), and (e) policy (education). Guardians and professionals agreed on the importance of enjoyment, interaction, and programs to promote PA. Differences between groups were identified at the organizational and policy levels. PA in persons with Down syndrome is influenced by interactions between individual and environmental factors.

Estimation of body fat in children with intellectual disability: development and cross-validation of a simple anthropometric method

Abstract Objective Population-level monitoring of body composition requires accurate, biologically-relevant, yet feasible methods for estimating percent body fat (%BF). The aim of this study was to develop and cross-validate an equation for %BF from Body Mass Index (BMI), age, and sex among children with intellectual disability (ID). This study further aimed to examine the performance of an existing BMI-based equation (Deurenberg equation) for %BF in children with ID. Method Participants were 107 children (63 boys; aged 6-15 years) with ID randomly allocated to development (n= 81) and cross-validation (n= 26) samples. Dual-Energy X-Ray Absorptiometry provided the criterion %BF. Results The model including BMI, age, and sex (0 = male; 1 = female) had a significant goodness-of-fit in determining %BF (p< 0.001; R2= 0.69; SEE =5.68%). The equation was: %BF = - 15.416 + (1.394 × BMI) + (4.538 × age) - (0.262 × age2) + (5.489 × sex). The equation was cross-validated in the separate sample based on (i) strong correlation (r = 0.82; p< 0.001) and non-significant differences between actual and predicted %BF (28.6 ± 9.6% and 30.1 ± 7.1%, respectively); (ii) mean absolute error (MAE) = 4.4%; and (iii) reasonable %BF estimations in Bland-Altman plot (mean: 1.48%; 95% CI: 12.5, -9.6). The Deurenberg equation had a large %BF underestimation (mean: -7.1%; 95% CI: 5.3, -19.5), significant difference between actual and estimated %BF (28.6 ± 9.7% and 21.5 ± 7.0%, respectively; p< 0.001), and MAE = 8.1%. Conclusions The developed equation with BMI, sex, and age provides valid %BF estimates for facilitating population-level body fat screening among children with ID.

Estimation of body fat in children with intellectual disability: development and cross-validation of a simple anthropometric method.

OBJECTIVE: Population-level monitoring of body composition requires accurate, biologically-relevant, yet feasible methods for estimating percent body fat (%BF). The aim of this study was to develop and cross-validate an equation for %BF from Body Mass Index (BMI), age, and sex among children with intellectual disability (ID). This study further aimed to examine the performance of an existing BMI-based equation (Deurenberg equation) for %BF in children with ID. METHOD: Participants were 107 children (63 boys; aged 6-15 years) with ID randomly allocated to development (n = 81) and cross-validation (n = 26) samples. Dual-Energy X-Ray Absorptiometry provided the criterion %BF. RESULTS: The model including BMI, age, and sex (0 = male; 1 = female) had a significant goodness-of-fit in determining %BF (p < 0.001; R2 = 0.69; SEE =5.68%). The equation was: %BF = - 15.416 + (1.394 × BMI) + (4.538 × age) - (0.262 × age2) + (5.489 × sex). The equation was cross-validated in the separate sample based on (i) strong correlation (r = 0.82; p < 0.001) and non-significant differences between actual and predicted %BF (28.6 ± 9.6% and 30.1 ± 7.1%, respectively); (ii) mean absolute error (MAE) = 4.4%; and (iii) reasonable %BF estimations in Bland-Altman plot (mean: 1.48%; 95% CI: 12.5, -9.6). The Deurenberg equation had a large %BF underestimation (mean: -7.1%; 95% CI: 5.3, -19.5), significant difference between actual and estimated %BF (28.6 ± 9.7% and 21.5 ± 7.0%, respectively; p < 0.001), and MAE = 8.1%. CONCLUSIONS: The developed equation with BMI, sex, and age provides valid %BF estimates for facilitating population-level body fat screening among children with ID.

Brief report: Caregiver perceived physical activity preferences of adults with Down syndrome.

BACKGROUND: Adults with Down syndrome commonly have low levels of physical activity and face social barriers to engaging in physical activity, including boredom and companionship concerns. Adults with Down syndrome are at increased risk for several co-occurring medial conditions known to benefit from physical activity, including obesity and dementia. METHOD: This study surveyed 140 caregivers of adults with Down syndrome to determine the physical activity preferences of their adult with Down syndrome. RESULTS: Dancing was the most frequently caregiver-reported physical activity preference for adults with Down syndrome, followed by walking and active video gaming. Rowing, using an elliptical machine, and jogging were the least preferred activities. Most caregivers reported that their adult with Down syndrome has a companion available for physical activity. CONCLUSION: Promoting dance in adults with Down syndrome, a caregiver-reported preferred form of physical activity, may help improve physical activity levels and decrease sedentary behaviours in this population.

Weight management recommendations for youth with Down syndrome: Expert recommendations.

Youth with Down syndrome (DS) have a higher prevalence of overweight and obesity compared to the general youth population. Due to physiological and cognitive differences observed in youth with DS, weight management recommendations developed for the general population, may not be suitable for youth with DS. However, there are no recent recommendations for weight management in youth with DS. A workgroup of clinicians and researchers with extensive experience working with youth with DS came together to give clinicians and families guidance for weight management in youth with DS. Recommendations were developed by the workgroup via a methodical, deliberative process. After the initial development of the recommendations, they were shared with an expert review panel and caregivers who rated the strength of the recommendation and strength of the evidence. The workgroup moved forward the recommendations which the review panels rated as strong. Eight recommendations were developed which focused on screening for overweight and obesity, screening for health conditions that may impact dietary intake and physical activity, screening for feeding difficulties, setting appropriate recommendations for dietary intake and physical activity, and well as prevention and treatment of overweight and obesity using evidence-based strategies. These recommendations can be implemented by clinicians working with youth with Down syndrome as well as the family, school, and other relevant entities.

Association between sleep quality and physical functioning in adults with Down syndrome: A brief report.

BACKGROUND: Sleep quality is associated with physical functioning in adults, but this has not been examined in those with Down syndrome (DS). High body mass index (BMI) and accelerated aging, both common in adults with DS, may alter the relationship between sleep quality and physical functioning in this population. OBJECTIVE: To examine sleep quality indicators and its association with physical functioning in adults with DS, and whether associations are altered by BMI and age. METHODS: Participants were 15 adults with DS (8 women; age 29 ± 14 years). We evaluated sleep quality over seven days with wrist-worn accelerometers and physical functioning with the timed-up-and-go (TUG) and 6-min walk (6 MW) tests. We examined the associations between sleep quality and physical functioning variables using Spearman's rho. RESULTS: Sleep quality indicators were: total sleep time 407 ± 54 min; latency 26.8 ± 21 min; efficiency 73.9 ± 12 %; wake after sleep onset 122.8 ± 65.2 min; number of awakenings 21.0 ± 6.2; and average length of awakenings 6.1 ± 3 min. Total sleep time and average length of awakenings were significantly associated with 6 MW distances (rho = 0.58 and -0.69; p < 0.05, respectively). After controlling for age and BMI, 6 MW distance was significantly associated with total sleep time, latency, efficiency, and average length of awakenings (rho = 0.56, -0.73, 0.60, and -0.87; p < 0.05, respectively). TUG was significantly associated with total time in bed (rho = 0.71); p < 0.05). CONCLUSIONS: Sleep quality indicators are associated with walking performance in adults with DS. Age and BMI strengthen the relationship between sleep quality and physical functioning.

Development and Cross-Validation of a Simple Model to Estimate Percent Body Fat in Persons with Multiple Sclerosis.

BACKGROUND: Persons with multiple sclerosis (MS) have higher body composition variability compared with the general population. Monitoring body composition requires accurate methods for estimating percent body fat (%BF). We developed and cross-validated an equation for estimating %BF from body mass index (BMI) and sex in persons with MS. METHODS: Seventy-seven adults with MS represented the sample for the equation development. A separate sample of 33 adults with MS permitted the equation cross-validation. Dual-energy x-ray absorptiometry (DXA) provided the criterion %BF. RESULTS: The model including BMI and sex (mean ± SD age: women, 49.2 ± 8.8 years; men, 48.6 ± 9.8 years) had high predictive ability for estimating %BF (P < .001, R2 = 0.77, standard error of estimate = 4.06%). Age, MS type, Patient-Determined Disease Steps score, and MS duration did not improve the model. The equation was %BF = 3.168 + (0.895 × BMI) - (10.191 × sex); sex, 0 = woman; 1 = man. The equation was cross-validated in the separate sample (age: women, 48.4 ± 9.4 years; men, 43.8 ± 15.4 years) based on high accuracy as indicated by strong association (r = 0.89, P < .001), nonsignificant difference (mean: 0.2%, P > .05), small absolute error (mean: 2.7%), root mean square error (3.5%), and small differences and no bias in Bland-Altman analysis (mean difference: 0.2%, 95% CI: -6.98 to 6.55, rs = -0.07, P = .702) between DXA-determined and equation-estimated %BF. CONCLUSIONS: Health care providers can use this developed and cross-validated equation for estimating adiposity in persons with MS when DXA is unavailable.

Opportunities, barriers, and recommendations in down syndrome research.

BACKGROUND: Recent advances in medical care have increased life expectancy and improved the quality of life for people with Down syndrome (DS). These advances are the result of both pre-clinical and clinical research but much about DS is still poorly understood. In 2020, the NIH announced their plan to update their DS research plan and requested input from the scientific and advocacy community. OBJECTIVE: The National Down Syndrome Society (NDSS) and the LuMind IDSC Foundation worked together with scientific and medical experts to develop recommendations for the NIH research plan. METHODS: NDSS and LuMind IDSC assembled over 50 experts across multiple disciplines and organized them in eleven working groups focused on specific issues for people with DS. RESULTS: This review article summarizes the research gaps and recommendations that have the potential to improve the health and quality of life for people with DS within the next decade. CONCLUSIONS: This review highlights many of the scientific gaps that exist in DS research. Based on these gaps, a multidisciplinary group of DS experts has made recommendations to advance DS research. This paper may also aid policymakers and the DS community to build a comprehensive national DS research strategy.

Levels and patterns of sedentary behavior in men and women with intellectual disability.

BACKGROUND: There are limited data on the levels and patterns of sedentary behavior (SB) among U.S. adults with ID. OBJECTIVE: To examine SB levels and patterns in U.S. adults with ID and how these differ between sexes, age-groups, and week vs. weekend days. METHODS: Fifty-two adults with ID (25 men; age 45 ± 14 years) wore a hip accelerometer (wGT3X-BT; Actigraph) during the waking hours for 7 days. We determined total sedentary time, percent of wear time spent sedentary bouts ≥1, ≥10, ≥30, and ≥60 min, and breaks in sedentary time for bouts ≥10 min. We examined differences in SB variables as a function of sex, age-group by median split (≤48 vs. >48 years), and day of the week. RESULTS: Total sedentary time was 514 ± 139 min · day-1 accumulated in bouts 1-30 min and did not differ between sexes or age-groups. Bouts ≥1 min across days were longer for men than women and longer during weekend days than weekdays (p < 0.05). The number of bouts ≥1 min was greater during weekdays than weekend days (p < 0.05). Bouts ≥60 min were longer for men than women (p < 0.05). The duration of sedentary breaks was longer during weekdays than weekend days (p < 0.001). There were no differences between age-groups. CONCLUSIONS: Adults with ID spend a large portion of the day in SB primarily of short bouts. Despite small differences, SB levels and patterns were similar for men and women with ID and across age-groups throughout the week.

Age-Group Differences in Body Mass Index, Weight, and Height in Adults With Down Syndrome and Adults With Intellectual Disability From the United States.

The authors examined if body mass index (BMI), weight, and height across age groups differ between adults with Down syndrome (DS) and adults with intellectual disability but without DS. They conducted secondary analyses of cross-sectional data from 45,803 individuals from the United States from 2009 to 2014 of the National Core Indicators Adult Consumer Survey across five age groups: 18-29, 30-39, 40-49, 50-59, and 60+ years. For both men and women with DS, BMI and weight increased between the 18- to 29- and the 30- to 39-year age groups and decreased thereafter. For both men and women with intellectual disability, BMI and weight increased between the 18- to 29- and the 30- to 39-year age groups, stayed about the same until the 50- to 59-year age group, and decreased thereafter. Height demonstrated a small but significant decrease with older age in all groups. These cross-sectional comparisons indicate that BMI and weight may start decreasing at a younger age in adults with DS than in adults with intellectual disability.

Triaxial accelerometer output predicts oxygen uptake in adults with Down syndrome.

PURPOSE: This study examined if the relationship between the rate of oxygen uptake (V̇O2) and output from hip-and wrist-worn accelerometers differs between adults with and without DS, and evaluated the accuracy of accelerometer output in estimating V̇O2. MATERIALS AND METHODS: Sixteen adults with DS (10 men) and 19 adults without DS (10 men) performed 12 tasks including physical activities and sedentary behaviors. We measured V̇O2 with portable spirometry and accelerometer output (vector magnitude [VM]) with hip- and wrist-worn accelerometers. We used multi-level regressions to predict V̇O2 from VM, group, body mass index (BMI), age, height, weight, and sex. We evaluated prediction accuracy with absolute percent error and Bland-Altman plots. RESULTS: For both hip- and wrist-accelerometers, VM and group significantly predicted V̇O2 (p ≤ 0.021). When BMI was added, BMI was a significant predictor but group was not. The final models included VM and BMI (p ≤ 0.001; R2 = 0.78 and 0.57, for hip and wrist accelerometer model, respectively). Absolute error was greater for the wrist- than the hip-accelerometer model (wrist: 37.9 ± 38.1%; hip: 22.5 ± 27.4%). CONCLUSIONS: Adults with DS have different V̇O2 to VM responses, and this appears due to their higher BMI. Predictability of V̇O2 from accelerometer output is better for hip- than wrist-worn accelerometers.IMPLICATIONS FOR REHABILITATIONOutput from a triaxial accelerometer has high potential in predicting the energy expenditure and classifying the intensity of physical activity and sedentary behavior in adults with Down syndrome.Accuracy of predicting energy expenditure from accelerometer output is better for hip- than wrist-worn triaxial accelerometers.The development of appropriate rehabilitation interventions that include physical activity for improving health and function in adults with Down syndrome requires accurate assessments of physical activity levels.

Risk factors associated with history of falls in adults with intellectual disability.

BACKGROUND: Adults with intellectual disability (ID) have a higher risk for falls than the general population. AIM: The purpose of this study was to identify risk factors for falls in adults with ID using objective measurements. METHODS: Eighty adults with ID (men 36 women 44 age 43 ±â€¯13 years) provided data on falls history, health problems or limitations in daily life, physical activity (PA), and physical performance. We conducted independent-samples t-tests, and Chi-square (χ2) tests to examine the difference between fallers and non-fallers. Multivariate logistic regressions were performed to identify the independent effects of risk factors for falls in adults with ID. RESULTS: Fallers had significantly lower SPPB, mobility, and moderate PA than non-fallers (p <  .05). Fallers were more likely to be older, need support with activities of daily living (ADLs), and have arthritis or rheumatism, walking problem, and limitations to participating in PA than non-fallers (p <  .05). Among these variables, only needing support with ADLs remained a significant independent predictor of falls in a multivariate model. CONCLUSION: Support need for ADLs can predict falls in individuals with ID. Caregivers may need to closely monitor adults with ID who need support for ADLs.

Development and Cross-Validation of a Prediction Equation for Estimating Percentage Body Fat From Body Mass Index in Young People With Intellectual Disability.

The purpose of this study was to develop and cross-validate an equation for estimating percentage body fat (%BF) from body mass index and other potential independent variables among young persons with intellectual disability. Participants were 128 persons with intellectual disability (62 women; age 16-24 years) split between development (n = 98) and cross-validation (n = 30) samples. Dual-energy X-ray absorptiometry served as the reference method for %BF. An equation including 1/body mass index and sex (0 = male; 1 = female) was highly accurate in estimating %BF (p < .001; R2 = .82; standard error of estimate = 5.22%). Mean absolute and root mean square errors were small (3.1% and 3.9%, respectively). A Bland-Altman plot indicated nearly zero mean difference between actual and predicted %BF with modest 95% confidence intervals. The prediction equation was %BF = 56.708 - (729.200 × [1/body mass index]) + (12.134 × sex). Health care professionals may use the prediction equation for monitoring %BF among young people with intellectual disability.

Predictors of perceived health in adults with an intellectual disability.

BACKGROUND: The effects of Intellectual disability (ID) levels, body mass index (BMI) categories, and other factors on perceived health status of adults with ID are not well-known. AIMS: We aimed to examine: (a) the relationship between perceived health and level of intellectual function; (b) the influence of different BMI categories on a perceived health; and (c) the effect of the modifiable behavioral factors on perceived health. METHODS AND PROCEDURES: We examined the aims using data from the 2013-2014 Adult Consumer Survey of the National Core Indicator. We extracted demographic (e.g. age, BMI) and modifiable behavior-related variables (e.g. physical activity participation, having a job) and used logistic regression models to analyze the relationships. OUTCOMES AND RESULTS: Logistic regressions showed that more severe ID level is associated with worse perceived health, but when other variables related to personal and behavioral characteristics were accounted for, this relationship was no longer significant. Obese adults with ID had worse perceived health than those with normal weight; this effect remained significant even after considering other variables. Those in the overweight category did not differ in perceived health status from those of normal weight. The effects of all modifiable behaviors on perceived health were significant. CONCLUSIONS AND IMPLICATIONS: Health promotion programs for adults with ID may benefit by consideration of modifiable behaviors.

Is Physical Activity Associated With Physical Performance in Adults With Intellectual Disability?

Physical activity (PA) and sedentary behavior may contribute to physical function in adults with intellectual disability (ID). This study examined whether objectively measured PA and sedentary behavior levels are associated with physical performance in adults with ID. Fifty-eight adults with ID (29 women and 29 men, age 44 ± 14 years) underwent a measurement of physical performance with the Short Physical Performance Battery (SPPB) and PA and sedentary time using a hip-worn accelerometer (wGT3X-BT; ActiGraph, Pensacola, FL). Moderate PA and age were significantly associated with the SPPB score (r = .39 and .34, respectively; p < .01). A hierarchical-regression model with moderate PA and age as independent variables indicated that moderate PA was a significant predictor of SPPB (p < .001; R2 = .153), but age was not (p = .123; R2 change = .036). Overall, moderate PA was significantly associated with the SPPB score, even after accounting for age, in adults with ID.

Systematic review of sedentary behaviour in people with Down syndrome across the lifespan: A clarion call.

BACKGROUND: Individuals with Down syndrome (DS) experience health disparities possibly associated with high levels of sedentary behaviour (SB). We systematically reviewed SB measurement, levels, patterns, correlates, consequences and interventions in people with DS across the lifespan. METHOD: We searched these databases: Embase; PubMed; Web of Science; Scopus; CINAHL; PsycINFO; SPORTDiscus; and Cochrane Library. We included quantitative studies published in English since 1 January 1990. RESULTS: We identified 17 eligible articles. Across studies, accelerometer-determined sedentary time was 552 min/day (median: 542; range 392-680 min/day). Sedentary time appeared higher than previously reported values in the general population, especially for youth with DS. Multivariate SB correlates were primarily familial and environmental. Sedentary behaviour consequences have not been exclusively studied. Motor skills training reduced SB in youth with DS. CONCLUSIONS: Sedentary behaviour research in this population is in early stages. Individuals with DS have high levels of SB that may be responsive to interventions.

Physical Activity Promotion for Persons Experiencing Disability: The Importance of Interdisciplinary Research and Practice.

This paper examines the need for interdisciplinary knowledge in the formation of public health models for health-promoting physical activity (PA) for people experiencing disability. PA promotion for people experiencing disability is a multifaceted endeavor and requires navigating a multitude of complicated and interactive factors. Both disability and health are multifaceted constructs and the relationship between PA and health is embedded within a complicated web of interactive influences. PA promotion must consider interacting biological and psychosocial factors within the person and in the sociopolitical environment. Models for research and practice need to evolve from value and belief systems that center on people experiencing disability without stigmatizing them. We argue that interdisciplinary research and practice is needed in navigating the intricacies of PA promotion toward improving the health of people experiencing disability and facilitating inclusion, empowerment, and dignity.