Reliability, measurement error and minimum detectable change in mobility measures: a cohort study of community-dwelling adults aged 50 years and over in Ireland

Community-based exercises improve health status in pre-frail older adults: A systematic review with meta-analysis

BACKGROUND

Pre-frailty is associated with increased healthcare utilization. Over the past decade, public health interventions such as community-based exercises to target pre-frailty have been increasingly studied. However, the effects of community-based exercises on clinical outcome measures amongst community-dwelling older adults with pre-frailty remain unclear. This review aims to better understand the effects of community-based exercise on physical function, cognition, quality of life and frailty status in community-dwelling pre-frail older adults. A secondary objective was to investigate the optimal exercise parameters on clinical outcomes.

METHODS

Searches of MEDLINE, CINAHL, Google Scholar and Web of Science databases were conducted. Articles were included if they were randomized controlled trials (RCTs), and excluded if the participants consist of less than 50% pre-frail community-dwelling older adults. Meta-analyses (where possible) with either a fixed- or random- effect(s) model, standardized mean difference (SMD), odds ratio (OR) and tests of heterogeneity were performed. Multivariable meta-regression was performed to identify predictors of statistically significant outcome measures. The risk of bias was assessed using the modified Cochrane Risk-of-Bias tool.

RESULTS

Twenty-two RCTs with 900 participants in the experimental group and 1015 participants in the control group were included. When compared to minimal intervention, community-based exercises significantly improved lower limb strength (10 RCTs, 384 participants in the experimental group and 482 participants in the control group) with SMD 0.67 (95% CI 0.29 to 1.04), and lower limb function (5 RCTs, 120 participants in the experimental group and 219 participants in the control group) with SMD 0.27 (95% CI 0.03 to 0.51). Those who have received community-based exercises were more likely to reverse from pre-frailty to healthy state (OR = 2.74, 95% CI 1.36 to 5.51) (6 RCTs, 263 participants in the experimental group and 281 participants in the control group). The frequency of exercise sessions was a significant predictor of the effect size for gait speed (P<0.05).

CONCLUSIONS

Community-based exercise intervention is superior to minimal intervention for improving health status in pre-frail older adults. This has implications on the implementation of community-based exercise intervention by healthcare providers and policymakers.

OTHER

Nil funding for this review. PROSPERO registration number CRD42022348556.

Test-retest reliability of joint position sense in the carpometacarpal joint among healthy adults

BACKGROUND

Accurate proprioception in the thumb carpometacarpal (CMC) joint is necessary during activities such as performing fine manipulative tasks, such as coin handling, opening doors, using keys, and pressing control buttons.

PURPOSE

The primary aim of the present study was to examine the test-retest reliability of CMC joint position sense (JPS) in healthy subjects. The secondary aim was to determine the most reliable JPS testing position for the thumb CMC joint.

STUDY DESIGN

This was a cross-sectional study of a convenience sample of healthy adults.

METHODS

Three thumb positions (20°, 30°, and 40° of thumb abduction) were measured twice on the same day by a single rater using a universal goniometer. The absolute error in degrees between each position and reposition was calculated. The intraclass correlation coefficient (2,1) was calculated for relative reliability. The standard error of the measurement was calculated.

RESULTS

Sixty-four healthy adults (mean age 27.8 years, standard deviation = 8.7) were assessed. The intraclass correlation coefficients were poor (-0.08 to 0.22), and the standard error of the measurement was 1.4° for all positions.

CONCLUSIONS

The joint position reproduction test for JPS using goniometry demonstrated poor test-retest reliability and acceptable measurement error in healthy adults.

The effect of Tai Chi lower extremity exercise on the balance control of older adults in assistant living communities

BACKGROUND

Although Tai Chi (TC) is an evidence-based fall prevention training for older adults, its effective movements remain unclear, which may limit the practice of TC. The purpose of this study was to compare the effectiveness of TC lower extremity exercise (TC LEE), the 8-form Tai Chi (8-form TC), and a stretching control intervention for improving balance and functional mobility among older adults.

METHODS

This was a randomized controlled trial. A total of 102 participants (79 ± 6 years old) were recruited from assisted living facilities. All participants were randomly assigned to the TC LEE (n = 40), 8-form TC (n = 31), and stretching (n = 31) groups in which they received the respective interventions for 16 weeks. The Berg Balance Scale (BBS), Timed Up and Go (TUG) test, and center of pressure (COP) measurements during quiet stance were collected prior to and following the 16-week interventions. Comparisons on all measurements were conducted among all groups.

RESULTS

Significant improvements were found in BBS (P = 0.002), TUG test (P = 0.001), root mean square amplitude of COP displacement in the anterior-posterior (P = 0.001) and medial-lateral (P = 0.001) directions, and average COP speed in the anterior-posterior (P = 0.001) and medial-lateral (P = 0.001) directions after training in the TC intervention groups compared with the stretching group. The upper limit of the 95% confidence interval (CI) of differences in change scores on the BBS (-0.8 - 1.3 points) between the TC LEE group and the 8-form TC group was within equivalence margins (1.8 points), while the upper limit of the 95% CI of differences in change scores on the TUG test (0.1 - 2.1 s) exceeded the equivalence margin (0.7 s) with the TC LEE group having the larger change scores.

CONCLUSION

TC LEE can improve balance and functional mobility in older adults, and may have greater effect than the 8-form TC on improving functional mobility as measured by the TUG test.

TRIAL REGISTRATION

ChiCTR2300070600 retrospectively registered.

CXCL10 upregulation in radiation-exposed human peripheral blood mononuclear cells as a candidate biomarker for rapid triage after radiation exposure

PURPOSE

In case of a nuclear accident, individuals with high-dose radiation exposure (>1-2 Gy) should be rapidly identified. While ferredoxin reductase (FDXR) was recently suggested as a radiation-responsive gene, the use of a single gene biomarker limits radiation dose assessment. To overcome this limitation, we sought to identify reliable radiation-responsive gene biomarkers.

MATERIALS AND METHODS

Peripheral blood mononuclear cells (PBMCs) were isolated from mice after total body irradiation, and gene expression was analyzed using a microarray approach to identify radiation-responsive genes.

RESULTS

In light of the essential role of the immune response following radiation exposure, we selected several immune-related candidate genes upregulated by radiation exposure in both mouse and human PBMCs. In particular, the expression of ACOD1 and CXCL10 increased in a radiation dose-dependent manner, while remaining unchanged following lipopolysaccharide (LPS) stimulation in human PBMCs. The expression of both genes was further evaluated in the blood of cancer patients before and after radiotherapy. CXCL10 expression exhibited a distinct increase after radiotherapy and was positively correlated with FDXR expression.

CONCLUSIONS

CXCL10 expression in irradiated PBMCs represents a potential biomarker for radiation exposure.

Mild Stroke, Serious Problems: Limitations in Balance and Gait Capacity and the Impact on Fall Rate, and Physical Activity

BACKGROUND

After mild stroke persistent balance limitations may occur, creating a risk factor for fear of falling, falls, and reduced activity levels. Objective. To investigate whether individuals in the chronic phase after mild stroke show balance and gait limitations, elevated fall risk, reduced balance confidence, and physical activity levels compared to healthy controls.

METHODS

An observational case-control study was performed. Main outcomes included the Mini-Balance Evaluation Systems Test (mini-BEST), Timed Up and Go (TUG), 10-m Walking Test (10-MWT), and 6-item version Activity-specific Balance Confidence (6-ABC) scale which were measured in 1 session. Objectively measured daily physical activity was measured for 7 consecutive days. Fall rate in daily life was recorded for 12 months. Individuals after a mild stroke were considered eligible when they: (1) sustained a transient ischemic attack or stroke longer than 6 months ago, resulting in motor and/or sensory loss in the contralesional leg at the time of stroke, (2) showed (near-) complete motor function, that is, ≥24 points on the Fugl-Meyer Assessment-Lower Extremity (range: 0-28).

RESULTS

Forty-seven healthy controls and 70 participants after mild stroke were included. Participants with stroke fell more than twice as often as healthy controls, had a 2 point lower median score on the mini-BEST, were 1.7 second slower on TUG, 0.6 km/h slower on the 10-MWT, and had a 12% lower 6-ABC score. Intensity for both total activity (8%) as well as walking activity (6%) was lower in the participants with stroke, while no differences were found in terms of duration.

CONCLUSIONS

Individuals in the chronic phase after a mild stroke demonstrate persistent balance limitations and have an increased fall risk. Our results point at an unmet clinical need in this population.

A system for monitoring the functional status of older adults in daily life

Functional decline in older adults can lead to an increased need of assistance or even moving to a nursing home. Utilising home automation, power and wearable sensors, our system continuously keeps track of the functional status of older adults through monitoring their daily life and allows health care professionals to create individualised rehabilitation programmes based on the changes in the older adult's functional capacity and performance in daily life. The system uses the taxonomy of the International Classification of Functioning, Disability and Health (ICF) by the World Health Organization (WHO). It links sensor data to five ICF items from three ICF categories and measures their change over time. We collected data from 20 (pre-)frail older adults (aged [Formula: see text] 75 years) during a 10-month observational randomised pilot intervention study. The system successfully passed the first pre-clinical validation step on the real-world data of the OTAGO study. Furthermore, an initial test with a medical professional showed that the system is intuitive and can be used to design personalised rehabilitation measures. Since this research is in an early stage further clinical studies are needed to fully validate the system.

Comparisons of Two Bioelectrical Impedance Devices and Manual versus Sensor-Based Short Physical Performance Batteries for Assessment of Muscle Mass and Physical Performance

The assessment of muscle mass and physical performance is essential for the diagnosis of sarcopenia. This study examined the validity of bioimpedance analysis (BIA) and a sensor-based short physical performance battery (SPPB) device for analyzing appendicular skeletal muscle mass (ASM) and physical performance. Forty-one older adults were measured for ASM and physical performance with two BIA devices (InBody770 vs. T-SCAN PLUS III) and two SPPB devices (manual mSPPB vs. sensor-based sSPPB). Validity statistics included the intraclass correlation coefficient (ICC) and Bland-Altman plots to examine the agreement of data from the BIA (InBody770 vs. T-SCAN PLUS III) and the SPPBs (mSPPB vs. sSPPB). There was a significant ICC for skeletal muscle mass between the T-SCAN PLUS III and InBody770 devices (ICC = 0.8822; p < 0.0001). The mSPPB and sSPPB values showed agreement across all components: 0.8654 for the total scores, 0.8879 for the walking speed, 0.8889 for the chair stand, and 0.6863 for the standing balance. No systemic bias was observed between the two methods for the BIA and SPPB devices. Measurements using the T-SCAN PLUS III and sSPPB seem to be highly correlated with the InBody770 and mSPPB devices in older adults and may be valid for assessing muscle mass and physical performance.

Arterial stiffness expressed as brachial-ankle pulse wave velocity and gait assessment independent of lower extremity strength: a cross-sectional study in the older men population

BACKGROUND

Older men are more vulnerable to fatal falls than women, and gait disturbances contribute to the risk of falls. Studies have assessed the association between arterial stiffness and gait dysfunction, but the results have been inconclusive. This study aimed to conduct a cross-sectional analysis to evaluate the association between brachial-ankle pulse wave velocity (baPWV) and gait assessment in older men.

METHODS

Data from the 2014-2015 Korea Institute of Sport Science Fitness Standards project were used for the analysis. The inclusion criteria were men aged > 65 years with gait assessment [the 30-s chair stand test (30s-CST), the timed up and go (TUG) test, the figure-of-8 walk (F8W) test, the 2-min step test (2MST), and the 6-min walk test (6MWT)] and baPWV measurement data. Generalized linear regression analysis was conducted with multiple confounding factor adjustments, including lower extremity isometric strength.

RESULTS

A total of 291 participants were included in the analysis. The mean age was 71.38 ± 4.40 years. The mean values were as follows: (1) 30s-CST, 17.48 ± 5.00; (2) TUG test, 6.01 ± 1.10 s; (3) F8W test, 25.65 ± 4.71 s; (4) 2MST, 102.40 ± 18.83 per 2 min; and (5) 6MWT, 500.02 ± 85.65 m. After multivariable adjustment, baPWV was associated with the 6MWT (β = -0.037, 95% CI: -0.072--0.002), TUG test (β = 0, 95% CI: 0.000-0.001), and F8W test (β = 0.002, 95% CI: 0.000-0.004). baPWV was not associated with the 30s-CST and 2MST.

CONCLUSIONS

The current study showed a statistically significant association between gait assessments and arterial stiffness, independent of lower extremity strength. However, this association was modest. Future prospective studies are needed to elucidate the complex relationship between arterial stiffness and gait dysfunction.

Implementing a Personalized Physical Therapy Approach (Coach2Move) Is Effective in Increasing Physical Activity and Improving Functional Mobility in Older Adults: A Cluster-Randomized, Stepped Wedge Trial

OBJECTIVE

The purpose of this study was to assess whether the superior cost-effectiveness of a personalized physical therapy approach (Coach2Move)-which was demonstrated in a previous trial compared with usual care physical therapy (UCP)-can be replicated in daily clinical practice.

METHODS

A multicenter, cluster-randomized, stepped wedge trial with 4 clusters consisting of 4 physical therapist practices in the Netherlands was used to compare a personalized physical therapy approach to elicit physical activity (Coach2Move) versus care as usual. Multilevel analyses for effectiveness were conducted for the amount of physical activity (Longitudinal Aging Study Amsterdam Physical Activity Questionnaire) and functional mobility (Timed "Up & Go" Test) at 3, 6 (primary outcome), and 12 months' follow-up. Secondary outcomes were level of frailty (Evaluative Frailty Index for Physical Activity), perceived effect (Global Perceived Effect and Patient-Specific Complaints Questionnaires), quality of life (Euro Quality of Life-5 Dimensions-5 Levels [EQ-5D-5L]), and health care expenditures.

RESULTS

The 292 community-dwelling older adults with mobility problems visiting physical therapists were included in either the Coach2Move (n = 112; mean [SD] age = 82 [5] years; 60% female) or UCP (n = 180; mean [SD] age = 81 (6) years; 62% female) section of the trial. At baseline, Coach2Move participants were less physically active compared with UCP participants (mean difference = -198; 95% CI = -90 to -306 active minutes). At 6 months, between-group mean differences [95% CI] favored Coach2Move participants on physical activity levels (297 [83 to 512] active minutes), functional mobility (-14.2 [-21 to -8]) seconds), and frailty levels (-5 [-8 to -1] points). At 12 months, the physical activity levels of Coach2Move participants further increased, and frailty levels and secondary outcomes remained stable, whereas outcomes of UCP participants decreased. After the Coach2Move implementation strategy, physical therapists utilized significantly fewer treatment sessions compared with before the implementation (15 vs 22). Anticipated cost savings were not observed.

CONCLUSION

This study replicated the results of an earlier trial and shows that Coach2Move leads to better mid- and long-term outcomes (physical activity, functional mobility, level of frailty) in fewer therapy sessions compared with UCP. Based on these and earlier findings, the implementation of Coach2Move in physical therapist practice is recommended.

IMPACT

This article describes the implementation of the Coach2Move approach, a treatment strategy that has proven to be cost-effective in a previously conducted randomized controlled trial. Implementation of Coach2Move in a real-life setting allowed an evaluation of the effects in a clinically relevant population. Coach2Move has been shown to increase physical activity, improve functional mobility, and reduce frailty more effectively compared with UCP therapy and therefore has application for physical therapists working with older adults in daily clinical practice.

LAY SUMMARY

Coach2Move is a new physical therapy approach for older adults. Implementation of Coach2Move in daily clinical practice can help people better outcomes over a longer period of time against similar costs compared with regular physical therapy.

Telerehabilitation in Older Thai Community-Dwelling Adults

To investigate the impact on physical performance and walking abilities associated with fall risk and disability in the senior population, we created a telerehabilitation system. This is a multi-site, community setting, pre−post experimental study. We recruited participants from four rural areas in Thailand. All participants received eight weeks of tele-exercise, three sessions per week, via the telerehabilitation system. After the intervention, all participants underwent the Short Physical Performance Battery (SPPB), Timed Up and Go (TUG) test, and the six-minute walk test (6MWT) using a wearable sensor system. A total of 123 participants participated in the study and 2 participants dropped out while conducting the study, thus 121 participants were included in the analysis. In comparison to the baseline, we discovered a considerable improvement in the SPPB score (0.65 ± 0.22, p < 0.001), TUG (−1.70 ± 0.86, p < 0.001), and 6MWT (10.23 ± 7.33, p = 0.007). Our study demonstrates the benefits of telerehabilitation on SPPB, TUG, and 6MWT related to disabilities and fall risk. This telerehabilitation technology demonstrated its viability in the community environment and demonstrated its capacity to offer fundamental components of remote rehabilitation services within the healthcare system.

Impaired ankle inversion proprioception during walking is associated with fear of falling in older adults

Background

Ankle proprioception plays a critical role in lower limb movement control. However, the relationship between ankle proprioception and fear of falling (FOF) in older people is still unclear.

Objective

(1) This study aims to develop a new device for measuring ankle inversion proprioceptive discrimination sensitivity during walking, i.e., the Ankle Inversion Discrimination Apparatus–Walking (AIDAW), and assess the test–retest reliability of the AIDAW in both young and older adults; (2) to evaluate the discriminant validity of the measure by comparing ankle proprioception during walking between the two groups; and (3) to explore convergent validity by determining to what extent the AIDAW proprioceptive scores correlate with Fall Efficacy Scale-International (FES-I) scores.

Materials and methods

The AIDAW was purpose-built to test ankle inversion proprioceptive discrimination sensitivity during walking. The area under the receiver operating curve (AUC) was calculated as the proprioceptive discrimination score. In total, 54 adults volunteered. Test–retest reliability was evaluated in 12 young and 12 older adults, and another 15 young and 15 older adults completed the comparison study. FOF was assessed by using the FES-I.

Results

The test–retest reliability intraclass correlation coefficient ICC _(3,1) value for the whole group was 0.76 (95% CI: 0.52–0.89). The ICC values of the young and older groups were 0.81 (95% CI: 0.46–0.94) and 0.71 (95% CI: 0.26–0.91), respectively. The Minimal Detectable Change with 90% confidence (MDC₉₀) values for the young and older groups were 0.03 and 0.11, respectively. There was a significant difference between the AIDAW proprioceptive sensitivity scores for the young and older groups (0.78 ± 0.04 vs. 0.72 ± 0.08, F = 5.06, p = 0.033). Spearman’s correlation analysis showed that the FES-I scores were significantly and negatively correlated with the AIDAW scores (rho = −0.61, p = 0.015), with higher FOF associated with worse ankle proprioception.

Conclusion

The AIDAW is a reliable and valid device for measuring ankle proprioception during walking in both young and older adults. Ankle inversion proprioceptive discrimination sensitivity during walking was found to be impaired in the elderly compared to young adults. This impairment was found to be strongly associated with FOF, suggesting that assessment and intervention for ankle proprioception in this population are needed to reduce the risk of falls.

The role of motivation factors in exergame interventions for fall prevention in older adults: A systematic review and meta-analysis

Balance disorders and falls are common in the elderly population. Regular balance exercises are an evidence-based physical intervention to prevent falls in older adults, while patient motivation and adherence are important factors for intervention outcome. Exergames are a relatively new, alternative intervention for physical rehabilitation as they improve balance and strength in older adults. The aims of this systematic review and meta-analysis were to assess the (1) effect of motivation factors as per the Capability, Opportunity and Motivation model of Behavior change (COM-B) on the effectiveness of exergame interventions in healthy older adults, (2) effectiveness of exergames to improve balance in older healthy adults and, (3) impact of exergames on cognitive outcomes. Results show that motivation and capability components influence the general outcome of the exergame training. Motivational factors should thus be considered when setting-up an exergame intervention. Furthermore, exergame intervention appears to be a promising training method in comparison to traditional exercise training. However, exergame training in itself might not be sufficient to improve fall risk and cognitive performance.

Feasibility of a 4-Week Manual Therapy and Exercise Intervention on Posture and Function in Community-Dwelling Older Adults: A Pilot Study

BACKGROUND AND PURPOSE

Thoracic hyperkyphosis is a common condition that progresses with aging and has been associated with impaired functional performance, increased risk of falls, and even mortality. Previous studies to improve posture primarily used exercise for durations of 3 months or longer. The purpose of this pilot study was to examine the feasibility of a manual therapy intervention in community-dwelling older adults over a 4-week time frame that is comparable to the typical clinical setting, to test the appropriateness and procedures for the measurement of posture and function in the older population with hyperkyphosis, and to collect preliminary data to describe change in posture and function measures.

METHODS

Twenty-four participants with hyperkyphosis or forward head posture were recruited, and 22 participants completed this pilot study. Feasibility was measured based on attendance, tolerance, safety, and retention. Issues with measurement procedures were recorded. The intervention included manual therapy and exercise 3 times a week for 4 weeks to target spinal and peripheral joint stiffness, muscle lengthening, and muscle activation. Outcomes included height, kyphotic index (KI), Block Test, Acromion to Table (ATT), Timed Up and Go (TUG), 5 times sit-to-stand (5XSTS), Functional Reach (FR), 2-minute walk test (2MWT), and Patient-Specific Functional Scale (PSFS). Data collected at visits 1, 6, and 12 were analyzed using 1-way repeated-measures multivariate analysis of variance.

RESULTS AND DISCUSSION

Measurement and intervention protocols were found to be feasible. A significant effect for the aggregate dependent variables change over time was found. Univariate analysis of each dependent variable showed significance except for FR. All postural measures (height, KI, Block Test, and ATT) significantly improved statistically. The KI and ATT exceed the minimal detectable change for clinical significance. Function showed statistical improvements in the TUG, 5XSTS, 2MWT, and PSFS. Clinical significance was reached with the PSFS. Seven of 9 measures showed a statistically significant change in just 2 weeks.

CONCLUSIONS

This pilot study suggests that manual therapy and exercise applied to older adults shows promise for improvement in measures of posture and functional performance in a clinically feasible 4-week time frame.

Relationship of Patellofemoral Osteoarthritis to Changes in Performance-based Physical Function Over 7 Years: The Multicenter Osteoarthritis Study

OBJECTIVE

To determine the relationship of patellofemoral osteoarthritis (PFOA) to changes in performance-based function over 7 years.

METHODS

There were 2666 participants (62.2 ± 8.0 yrs, BMI 30.6 ± 5.9 kg/m2, 60% female) from the Multicenter Osteoarthritis Study with knee radiographs at baseline who completed repeated chair stands and a 20-meter walk test (20MWT) at baseline, 2.5, 5, and 7 years. Generalized linear models assessed the relation of radiographic PFOA and radiographic PFOA with frequent knee pain to longitudinal changes in performance-based function. Analyses were adjusted for age, sex, BMI, tibiofemoral OA, and injury/surgery.

RESULTS

Linear models demonstrated a significant group-by-time interaction for the repeated chair stands (P = 0.04) and the 20MWT (P < 0.0001). Those with radiographic PFOA took 1.01 seconds longer on the repeated chair stands (P = 0.02) and 1.69 seconds longer on the 20MWT (P < 0.0001) at 7 years compared with baseline. When examining the relation of radiographic PFOA with frequent knee pain to performance-based function, there was a significant group-by-time interaction for repeated chair stands (P = 0.05) and the 20MWT (P < 0.0001). Those with radiographic PFOA with frequent knee pain increased their time on the repeated chair stands by 1.12 seconds (P = 0.04) and on the 20MWT by 1.91 seconds (P < 0.0001) over 7 years.

CONCLUSION

Individuals with radiographic PFOA and those with radiographic PFOA with frequent knee pain have worsening of performance-based function over time. This knowledge may present opportunities to plan for early treatment strategies for PFOA to limit functional decline over time.

Timed "Up & Go" Dual-Task Tests: Age- and Sex-Specific Reference Values and Test-Retest Reliability in Cognitively Healthy Controls

OBJECTIVE

The purpose of the study was to establish reference values for the Uppsala-Dalarna Dementia and Gait (UDDGait) Timed "Up & Go" dual-task (TUGdt) test variables in cognitively healthy adults and to assess these variables' test-retest reliability.

METHODS

For reference values, 166 participants were recruited with approximately equal numbers and proportions of women and men in the age groups 50 to 59, 60 to 69, 70 to 79, and 80+ years (mean age = 70 years, age range = 50-91 years, 51% women). For reliability testing, 43 individuals (mean age = 69 years, age range = 50-89 years, 51% women) were recruited. Two dt tests were carried out: TUGdt naming animals and TUGdt months backward, representing 8 test variables: time scores, costs (the relative difference between single-task and dt time scores), "number of animals," "number of months," "animals/10 seconds ," and "months/10 seconds ." Reference ranges for the variables were established by quantile regression in age- and sex-specific groups. For reliability, intraclass correlation coefficients (ICCs), standard error of measurement, minimal detectable change, and Bland-Altman plots were used.

RESULTS

Reference values for the TUGdt test variables are presented for the 2.5th and 97.5th percentiles. The reliability of TUGdt time scores was excellent (ICCs between 0.85 and 0.86). "Number of animals" and "animals/10 seconds" as well as "months/10 seconds" showed fair to good levels of reliability (ICCs between 0.45 and 0.58), whereas the reliability for both cost measures and "number of months" was poor (ICCs between 0.34 and 0.39).

CONCLUSION

Normative reference values, potentially useful for clinical and research purposes, were presented in 4 age- and sex-specific groups from 50 years and older. Reliability for the test variables varied between poor and excellent, the lower estimates partly explained by some variables being the ratio of 2 other variables. In UDDGait, TUGdt tests are intended for diagnostic and predictive purposes, for which these tests are promising and require further investigations.

IMPACT

Normative reference values and test-retest reliability results for the UDDGait TUGdt test variables were presented. These results should be useful for both clinical and research purposes.

Reliability and minimal detectable change values for performance-based measures of physical functioning in the Canadian Longitudinal Study on Aging (CLSA)

BACKGROUND

The aim of this study was to determine the relative and absolute reliabilities of five key performance-based measures of physical function in the Canadian Longitudinal Study on Aging (CLSA).

METHODS

An age-stratified sub-sample of 147 participants from the CLSA who were undergoing their 3-year data collection visit participated in two repeat visits (within one week). Participants underwent tests of grip strength, 4-metre gait speed, Timed Up and Go (TUG), chair-rise and single-leg stance (left, right, mean, maximum). Intra-class correlation coefficients (ICC), standard error of measurement (SEM) and minimal detectable change (MDC) values were calculated.

RESULTS

The relative reliability for grip strength was excellent (ICC = 0.95); the TUG and single-leg stance tests had good reliability (ICC = 0.80 or 0.78-0.82, respectively); gait speed and the chair-rise test had moderate reliability (ICC=0.64 for both) for participants overall. For participants between 50 and 64 years, TUG and gait speed had poor reliabilities (ICC = 0.38 or 0.33, respectively). For participants aged 75+ years, the single-leg stance had poor reliability (ICC=0.30-0.39). The MDC90 was about 6 kg for grip strength, 2.3 seconds for TUG, 0.2 metres/second for gait speed, 5.2 seconds for chair-rise, and ranged from 22.8 to 26.2 seconds for the single-leg stance.

CONCLUSIONS

Among community-dwelling Canadians >50 years old, the reliabilities of the CLSA measures were moderate to excellent. The TUG and gait speed in the youngest age group, and the single-leg stance in oldest age group, showed poor reliability. MDC values can be used to interpret changes over time.

A comparison of physical exercise and cognitive training interventions to improve determinants of functional mobility in healthy older adults

OBJECTIVES

Mobility is a complex but crucial clinical outcome in older adults. Past observational studies have highlighted that cardiorespiratory fitness (CRF), energy cost of walking (ECW), and cognitive switching abilities are associated with mobility performance, making these key determinants of mobility intervention targets to enhance mobility in older adults. The objective of this study was to compare, in the same design, the impact of three training methods - each known to improve either CRF, ECW, or cognitive switching abilities - on mobility in healthy older adults.

METHODS

Seventy-eight participants (69.28 ± 4.85yo) were randomly assigned to one of three twelve-week interventions: Aerobic Exercise (AE; n = 26), Gross Motor Abilities (GMA; n = 27), or Cognitive (COG; n = 25) training. Each intervention was designed to improve one of the three key determinants of mobility (CRF, ECW, and cognitive switching). Primary outcomes (usual gait speed, and TUG performance) and the three mobility determinants were measured before and after the intervention.

RESULTS

Repeated-measures ANOVAs showed a time effect for TUG performance (F_(1,75) = 14.92, p < .001): all groups equally improved after the intervention (Δ_TUGpost-pre, in seconds, with 95% CI: AE = -0.44 [-0.81 to -0.08]; GMA = -0.60 [-1.10 to -0.10]; COG = -0.33 [-0.71 to 0.05]). No significant between group differences were observed. CRF was improved in the AE group only (Hedges' G = 0.27, small effect), ECW and cognitive switching improved the most in the GMA (Hedges' G = -0.78, moderate effect) and COG groups (Hedges' G = -1.93, large effect) respectively. Smaller improvements in ECW were observed following AE and COG trainings (Hedges' G: AE = -0.39, COG = -0.36, both small effects) as well as in cognitive switching following AE and GMA training (Hedges' G: AE = -0.42, GMA = -0.21, both small effects).

DISCUSSION

This study provides further support to the notion that multiple interventional approaches (aerobic, gross motor exercise, or cognitive training) can be employed to improve functional mobility in older adults, giving them, and professionals, more options to promote healthy ageing.

Intra-Individual Variation and Reliability of Biomarkers of the Antioxidant Defense System by Considering Dietary and Lifestyle Factors in Premenopausal Women

Epidemiological studies frequently rely on a single biomarker measurement to assess the relationship between antioxidant status and diseases. This bears an inherent risk for misclassification, if the respective biomarker has a high intra-individual variability. The present study investigates the intra-individual variation and reliability of enzymatic and non-enzymatic biomarkers of the antioxidant system in premenopausal women. Forty-four apparently healthy females provided three consecutive fasting blood samples in a four-week rhythm. Analyzed blood biomarkers included Trolox equivalent antioxidant capacity (TEAC), catalase, glutathione peroxidase, glutathione, vitamin C, bilirubin, uric acid, coenzyme Q10, tocopherols, carotenoids and retinol. Intra- and inter-individual variances for each biomarker were estimated before and after adjusting for relevant influencing factors, such as diet, lifestyle and use of contraceptives. Intraclass correlation coefficient (ICC), index of individuality, reference change value and number of measurements needed to confine attenuation in regression coefficients were calculated. Except for glutathione and TEAC, all biomarkers showed a crude ICC ≥ 0.50 and a high degree of individuality indicating that the reference change value is more appropriate than population-based reference values to scrutinize and classify intra-individual changes. Apart from glutathione and TEAC, between 1 and 9 measurements were necessary to reduce attenuation in regression coefficients to 10%. The results indicate that the majority of the assessed biomarkers have a fair to very good reliability in healthy premenopausal women, except for glutathione and TEAC. To assess the status of the antioxidant system, the use of multiple measurements and biomarkers is recommended.

Choice reaction time and subsequent mobility decline: Prospective observational findings from The Irish Longitudinal Study on Ageing (TILDA)

BACKGROUND

Cognitive and motor function in ageing are intertwined, but whether slower motor response time (MRT) to a cognitive stimulus could herald accelerated mobility decline is unknown. Using data from The Irish Longitudinal Study on Ageing (TILDA), we examined whether slower MRT may predict a greater than expected increase in Time Up and Go (TUG) after 4 years.

METHODS

Participants aged 50 years or older were divided into two groups based on their mean MRT (< 250 ms versus ≥ 250 ms). A repeated measures ANOVA compared TUG trajectories between groups, controlling for baseline age, sex, height, education level, mini mental-state examination (MMSE) score, self-reported vision and hearing, medical conditions (cardiovascular, cerebrovascular disease, diabetes), and number of medications.

FINDINGS

At Wave 1, 1982 (58.7%) had a mean MRT of < 250 ms, with a mean TUG of 8.1 s (SD 1.6); and 1397 (41.3%) had an MRT of ≥ 250 ms, with a TUG of 9.0 s (SD 2.2). At Wave 3, TUG increased to 8.8 s (SD 2.0) and 10.2 s (SD 3.9), respectively. The results of the adjusted repeated measures ANOVA suggested that there was a statistically significant interaction between MRT group and Wave (P = 0.023, η² _p = 0.002).

INTERPRETATION

TILDA participants in the slower MRT group seemed to have faster mobility decline, but this effect was statistically and clinically small.

FUNDING

TILDA is funded by Atlantic Philanthropies, the Irish Department of Health and Irish Life. Roman Romero-Ortuno is funded by Science Foundation Ireland (grant number 18/FRL/6188).

Mobility in Older Community-Dwelling Persons: A Narrative Review

Due to the demographic changes and the increasing awareness of the role of physical function, mobility in older age is becoming an important topic. Mobility limitations have been reported as increasingly prevalent in older persons affecting about 35% of persons aged 70 and the majority of persons over 85 years. Mobility limitations have been associated with increased fall risk, hospitalization, a decreased quality of life, and even mortality. As concepts of mobility are multifactorial and complex, in this narrative review, definitions, physical factors, and their age-related changes associated with mobility will be presented. Also, areas of cognitive decline and their impact on mobility, as well as neuromuscular factors related to mobility will be addressed. Another section will relate psychological factors such as Fall-related psychological concerns and sedentary behavior to mobility. Assessment of mobility as well as effective exercise interventions are only shortly addressed. In the last part, gaps and future work on mobility in older persons are discussed.

Differences between two types of dual tasks according to the educational level in older adults

INTRODUCTION

For dual-task paradigms, the timed up and go (TUG) test along with other cognitive or motor tasks has been used to evaluate and predict the risk of falling in older adults. However, the interference between motor-cognitive tasks can differ by the cognitive task.

OBJECTIVE

To evaluate the performance of the TUG test under a single task condition and two dual-task conditions in older adults and to explore the effect of educational level on task performance.

METHODS

A total of 418 older adults (328 females) voluntarily participated in this study. The TUG test was administered as a single task and a dual task with one secondary simultaneous task: counting aloud backward from 100 or naming animals. Comparisons were performed to determine the interference caused by each cognitive task on the motor task, and correlation analysis was performed to explore the role of educational level.

RESULTS

The animal task led to a poorer TUG performance and a higher dual-task cost than did the counting task. Furthermore, the motor task led to a higher percentage of errors and cognitive stops in the animal task. Educational level plays a significant role in the interaction between tasks.

CONCLUSIONS

Between-task interference differs by the type of cognitive task performed and the educational level of the participants. The results of the present study should be considered when dual-task assessments are planned for older adults.

Reliability of 30-s Chair Stand Test with and without Cognitive Task in People with Type-2 Diabetes Mellitus

Background: Reliability refers to the precision of an assessment, so it is a critical topic to take the right decisions related to health management. People usually perform several tasks at the same time in their daily life. The aim of this study was to examine the reliability of the 30-s chair stand test in people with type 2 Diabetes Mellitus (T2DM) with test–retest, with and without dual-task (motor + cognitive task). Methods: Twenty-six subjects with T2DM and 30 subjects without T2DM performed the 30-s Chair Stand Test (30sCST) in which they must sit and stand as many times as possible in 30 s. They performed the test in the usual way (30sCST) and also with an additional cognitive task (30sCST-DT). A retest was conducted 7–14 days later. Results: Relative reliability was excellent in both groups (intraclass correlation coefficient > 0.9). In 30sCST-DT, relative reliability was high in the T2DM group (intraclass correlation coefficient > 0.7) and excellent in subjects without T2DM (intraclass correlation coefficient > 0.9). Conclusions: The 30sCST and the 30sCST-DT tests are reliable tools for people with T2DM to measure changes after an intervention. The smallest real difference was 15% and 20% upper in the T2DM group in the 30sCST and 30sCST-DT tests, respectively.