Comparing the effects of dual-task training and single-task training on walking, balance and cognitive functions in individuals with Parkinson's disease: A systematic review.

BACKGROUND: This systematic review aimed to examine whether dual-task (DT) training was superior to single-task (ST) training in improving DT walking, balance and cognitive function for individuals with Parkinson's disease (PD). METHODS: Literature search was performed in the following electronic databases: PubMed, the Cochrane Library, Web of Science, and Metstr covering inception to May 10, 2023. And in order to facilitate comparison across trials, we calculated the effect size (Hedges' g) of gait, balance, cognitive, and other parameters under both ST and DT conditions, using the mean change score and standard deviation (SD) of change score of the experimental and control groups. Randomized controlled trials that examined the effects of DT motor and cognitive training in individuals with Parkinson's disease were included for this systematic review. RESULTS: A total of 335 participants recruited from six articles (five studies) were involved in this review. In terms of walking function, only double support time and stride time variability showed significant between-group difference (Hedges' g = 0.34, 0.18, respectively). Compared to ST training group, DT training group had a more improvement effect in laboratory balance measurement (Hedges' g = 0.18, 0.25), but no significant improvement in clinical balance measurement. No significant between-group differences were observed, thus its training effect on cognitive function was inconclusive. CONCLUSIONS: The DT training failed to achieve promising results better than ST training in improving DT walking and balance functions for individuals with PD. Any firm conclusion cannot be drawn at present, due to the limited number of eligible publications. Larger sample size and high-quality studies are needed to investigate the effectiveness of DT training in individuals with PD.

The Diagnostic Accuracy of Transcranial Color-Coded Doppler Ultrasound Technique in Stratifying Intracranial Cerebral Artery Stenoses in Cerebrovascular Disease Patients: A Systematic Review and Meta-Analysis.

The early and accurate stratification of intracranial cerebral artery stenosis (ICAS) is critical to inform treatment management and enhance the prognostic outcomes in patients with cerebrovascular disease (CVD). Digital subtraction angiography (DSA) is an invasive and expensive procedure but is the gold standard for the diagnosis of ICAS. Over recent years, transcranial color-coded Doppler ultrasound (TCCD) has been suggested to be a useful imaging method for accurately diagnosing ICAS. However, the diagnostic accuracy of TCCD in stratifying ICASs among patients with CVD remains unclear. Therefore, this systematic review and meta-analysis aimed at evaluating the diagnostic accuracy of TCCD in the stratification of intracranial steno-occlusions among CVD patients. A total of six databases-Embase, CINAHL, Medline, PubMed, Google Scholar, and Web of Science (core collection)-were searched for studies that assessed the diagnostic accuracy of TCCD in stratifying ICASs. The meta-analysis was performed using Meta-DiSc 1.4. The Quality Assessment of Diagnostic Accuracy Studies tool version 2 (QUADAS-2) assessed the risk of bias. Eighteen studies met all of the eligibility criteria. TCCD exhibited a high pooled diagnostic accuracy in stratifying intracranial steno-occlusions in patients presenting with CVD when compared to DSA as a reference standard (sensitivity = 90%; specificity = 87%; AUC = 97%). Additionally, the ultrasound parameters peak systolic velocity (PSV) and mean flow velocity (MFV) yielded a comparable diagnostic accuracy of "AUC = 0.96". In conclusion, TCCD could be a noble, safe, and accurate alternative imaging technique to DSA that can provide useful diagnostic information in stratifying intracranial steno-occlusions in patients presenting with CVD. TCCD should be considered in clinical cases where access to DSA is limited.

A Comparative Study of Transcranial Color-Coded Doppler (TCCD) and Transcranial Doppler (TCD) Ultrasonography Techniques in Assessing the Intracranial Cerebral Arteries Haemodynamics.

Cerebrovascular disease (CVD) poses a major public health and socio-economic burden worldwide due to its high morbidity and mortality rates. Accurate assessment of cerebral arteries' haemodynamic plays a crucial role in the diagnosis and treatment management of CVD. The study compared a non-imaging transcranial Doppler ultrasound (TCD) and transcranial color-coded Doppler ultrasound (with (cTCCD) and without (ncTCCD)) angle correction in quantifying middle cerebral arteries (MCAs) haemodynamic parameters. A cross-sectional study involving 50 healthy adults aged ≥ 18 years was conducted. The bilateral MCAs were insonated via three trans-temporal windows (TTWs-anterior, middle, and posterior) using TCD, cTCCD, and ncTCCD techniques. The MCA peak systolic velocity (PSV) and mean flow velocity (MFV) were recorded at proximal and distal imaging depths that could be visualised on TCCD with a detectable spectral waveform. A total of 152 measurements were recorded in 41 (82%) subjects with at least one-sided open TTW across the three techniques. The mean PSVs measured using TCD, ncTCCD, and cTCCD were 83 ± 18 cm/s, 81 ± 19 cm/s, and 93 ± 21 cm/s, respectively. There was no significant difference in PSV between TCD and ncTCCD (bias = 2 cm/s, p = 1.000), whereas cTCCD yielded a significantly higher PSV than TCD and ncTCCD (bias = -10 cm/s, p < 0.001; bias = -12 cm/s, p ≤ 0.001, respectively). The bias in MFV between TCD and ncTCCD techniques was (bias = -0.5 cm/s; p = 1.000), whereas cTCCD demonstrated a higher MFV compared to TCD and ncTCCD (bias = -8 cm/s, p < 0.001; bias = -8 cm/s, p ≤ 0.001, respectively). TCCD is a practically applicable imaging technique in assessing MCA blood flow velocities. cTCCD is more accurate and tends to give higher MCA blood flow velocities than non-imaging TCD and ncTCCD techniques. ncTCCD is comparable to non-imaging TCD and should be considered in clinical cases where using both TCD and TCCD measurements is needed.

The effect of dual-task training on cognitive ability, physical function, and dual-task performance in people with dementia or mild cognitive impairment: A systematic review and meta-analysis.

OBJECTIVE: To summarize the effect of dual-task training on cognitive, physical function, and dual-task performance in people with mild cognitive impairment or dementia. DATA SOURCES: Embase, PEDro, PsycINFO, PubMed, CINAHL, The Cochrane Library, and a forward search conducted via Web of Science have been searched from inception to July 2023. REVIEW METHODS: Good-quality randomized controlled trials compared dual-task training with no/placebo intervention or single-task training among people with a primary diagnosis of mild cognitive impairment or dementia were included. The PEDro scale was used to evaluate the methodological quality of individual studies. The Grading of Recommendations, Assessment, Development and Evaluations system was adopted to appraise the quality of evidence for each outcome. RESULTS: Eighteen trials (1325 participants) were included, and 17 provided data for meta-analysis. Comparing with no intervention, dual-task training led to significant improvements on attention (mean difference (MD) = -20.66, 95%CI [-39.42, -1.90]), functional mobility (MD = -2.73; 95%CI [-3.98, -1.49]). Compared with single-task training, dual-task training had greater effects on overall cognitive function (standardized mean difference (SMD) = 0.29, 95%CI [0.09, 0.49]), balance (SMD = 0.78, 95%CI [0.40, 1.15]) and functional mobility (MD = -1.17; 95%CI [-1.77, -0.58]). Its effect on dual-task performance remains inconclusive due to the inconsistent results reported. CONCLUSION: Low- to moderate-quality evidence supports that dual-task training has beneficial effects on cognitive function and physical function in individuals with dementia or mild cognitive impairment. The optimal training protocol of dual-task training on cognitive and physical functions, and dual-task performance remains uncertain. Well-designed, randomized studies with large enough sample sizes are warranted.

Predictors of chronic pain and disability in patients treated conservatively after distal radius fracture: a prospective cohort study.

PURPOSE: To determine predictors of chronic pain and disability among patients with distal radius fractures (DRF) treated conservatively with closed reduction and cast immobilization. METHODS: This was a prospective cohort study. Information on patient characteristics, post-reduction radiographic parameters, finger and wrist range of motion, psychological status (Hospital Anxiety and Depression Scale or HADS), pain (Numeric Rating Scale or NRS), and self-perceived disability (Disabilities of the Arm, Should, and Hand or DASH) were taken at baseline, cast removal, and 24 weeks. Differences in outcomes between time points were determined using analysis of variance. Multiple linear regressions were used to determine predictors of pain and disability at 24 weeks. RESULTS: One hundred forty patients with DRF (70% women, age: 67.0 ± 17.9) completed 24 weeks of follow-up and were included in the analysis. NRS (off-cast), range of ulnar deviation (off-cast), and greater occupational demands were significant predictors of pain at week 24 (adjusted R2 = 0.331, p < 0.001). Significant predictors of perceived disability at week 24 were HADS (off cast), sex (female), dominant-hand injury, and range of ulnar deviation (off cast) (adjusted R2 = 0.265, p < 0.001). CONCLUSIONS: Off-cast NRS and HADS scores are important modifiable predictors of patient-reported pain and disability at 24 weeks in patients with DRF. These factors should be targeted in the prevention of chronic pain and disability post-DRF.

Effect of physical exercise on fear of falling in patients with stroke: A systematic review and meta-analysis.

OBJECTIVE: To consolidate the evidence on the effect of physical exercise on fear of falling in individuals with stroke. DATA SOURCES: PubMed, CINAHL, Cochrane Database and MEDLINE. METHODS: An extensive database search was conducted to identify the randomised controlled trials that examined the effect of physical exercise on fear of falling post-stroke. Grading of Recommendation, Assessment, Development and Evaluation (GRADE) was used to assess the quality of evidence for each meta-analysis. RESULTS: Fourteen trials totalling 1211 participants were included in this review. Thirteen of these (1180 participants) were included in the meta-analyses. In the primary analysis, very low-quality evidence suggested that exercise reduced fear of falling post-stroke (standardized mean difference (SMD) 0.48; 95% confidence interval (CI) 0.23 to 0.72). The effect was diminished at three- to six-month follow-up after exercise training ended (SMD -0.09; 95% CI -0.27 to 0.10; high-quality evidence). In the sensitivity analyses, the treatment effect was more pronounced in individuals with a lower baseline Berg balance score (BBS ≤45; SMD 0.53; 95%CI 0.17 to 0.88) and for those trials with exercise frequency of ≥3 sessions per week (SMD 0.70; 95%CI 0.39 to 1.01). Compared with circuit-based training consisting of a combination of walking, balance and strengthening exercises (SMD 0.27; 95% CI -0.09 to 0.63), walking programmes seemed to generate a larger effect on fear of falling (SMD 1.06; 95%CI 0.43 to 1.70). CONCLUSION: Physical exercise was beneficial for reducing fear of falling in individuals with stroke, particularly those with poorer balance ability.

Diagnostic Efficacy of Advanced Ultrasonography Imaging Techniques in Infants with Biliary Atresia (BA): A Systematic Review and Meta-Analysis.

The early diagnosis of biliary atresia (BA) in cholestatic infants is critical to the success of the treatment. Intraoperative cholangiography (IOC), an invasive imaging technique, is the current strategy for the diagnosis of BA. Ultrasonography has advanced over recent years and emerging techniques such as shear wave elastography (SWE) have the potential to improve BA diagnosis. This review sought to evaluate the diagnostic efficacy of advanced ultrasonography techniques in the diagnosis of BA. Six databases (CINAHL, Medline, PubMed, Google Scholar, Web of Science (core collection), and Embase) were searched for studies assessing the diagnostic performance of advanced ultrasonography techniques in differentiating BA from non-BA causes of infantile cholestasis. The meta-analysis was performed using Meta-DiSc 1.4 and Comprehensive Meta-analysis v3 software. Quality Assessment of Diagnostic Accuracy Studies tool version 2 (QUADAS-2) assessed the risk of bias. Fifteen studies consisting of 2185 patients (BA = 1105; non-BA = 1080) met the inclusion criteria. SWE was the only advanced ultrasonography technique reported and had a good pooled diagnostic performance (sensitivity = 83%; specificity = 77%; AUC = 0.896). Liver stiffness indicators were significantly higher in BA compared to non-BA patients (p < 0.000). SWE could be a useful tool in differentiating BA from non-BA causes of infantile cholestasis. Future studies to assess the utility of other advanced ultrasonography techniques are recommended.

Low-Frequency rTMS over Contralesional M1 Increases Ipsilesional Cortical Excitability and Motor Function with Decreased Interhemispheric Asymmetry in Subacute Stroke: A Randomized Controlled Study.

Objective: To determine the long-term effects of low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) over the contralesional M1 preceding motor task practice on the interhemispheric asymmetry of the cortical excitability and the functional recovery in subacute stroke patients with mild to moderate arm paresis. Methods: Twenty-four subacute stroke patients were randomly allocated to either the experimental or control group. The experimental group underwent rTMS over the contralesional M1 (1 Hz), immediately followed by 30 minutes of motor task practice (10 sessions within 2 weeks). The controls received sham rTMS and the same task practice. Following the 2-week intervention period, the task practice was continued twice weekly for another 10 weeks in both groups. Outcomes were evaluated at baseline (T0), at the end of the 2-week stimulation period (T1), and at 12-week follow-up (T2). Results: The MEP (paretic hand) and interhemispheric asymmetry, Fugl-Meyer motor assessment, Action Research Arm Test, and box and block test scores improved more in the experimental group than controls at T1 (p < 0.05). The beneficial effects were largely maintained at T2. Conclusion: LF-rTMS over the contralesional M1 preceding motor task practice was effective in enhancing the ipsilesional cortical excitability and upper limb function with reducing interhemispheric asymmetry in subacute stroke patients with mild to moderate arm paresis. Significance. Adding LF-rTMS prior to motor task practice may reduce interhemispheric asymmetry of cortical excitabilities and promote upper limb function recovery in subacute stroke with mild to moderate arm paresis.

Degree and pattern of dual-task interference during walking vary with component tasks in people after stroke: a systematic review.

QUESTIONS: What are the degree and pattern of dual-task interference during walking in people after stroke? How do these vary with disease chronicity and different component tasks in people after stroke? How does dual-task interference differ between people after stroke and people without stroke? DESIGN: Systematic review with meta-analysis of studies reporting gait-related dual-task interference. PARTICIPANTS: People after stroke and people without stroke. OUTCOME MEASURES: Measures of walking and secondary (cognitive or manual) task performance under dual-task conditions relative to those under single-task conditions. RESULTS: Seventy-six studies (2,425 people after stroke and 492 people without stroke) were included. Manual and mental tracking tasks imposed the greatest dual-task interference on gait speed, although there was substantial uncertainty in these estimates. Among mental tracking tasks, the apparently least-complex task (serial 1 subtractions) induced the greatest dual-task interference (-0.17 m/s, 95% CI -0.24 to -0.10) on gait speed, although there was substantial uncertainty in these estimates. Mutual interference (decrement in both walking and secondary component task performances during dual-tasking) was the most common dual-task interference pattern. The results of the sensitivity analyses for studies involving people with chronic stroke were similar to the results of the primary analyses. The amount of dual-task interference from a mental tracking or manual task during walking was similar between people with or without stroke. CONCLUSIONS: The degree and pattern of dual-task interference vary with the choice of component tasks. When evaluating limitations to functional mobility during dual-tasking conditions and in planning interventions accordingly, clinicians should select dual-task assessments that correspond to the daily habits and physical demands of people after stroke. REGISTRATION: CRD42017059004.

A randomised controlled trial of expressive arts-based intervention for young stroke survivors.

BACKGROUND: Stroke causes lasting brain damage that has numerous impacts on the survivor's physical, psychosocial, and spiritual well-being. Young survivors (< 65 years old) tend to suffer more because of their longer overall survival time. Expressive arts-based intervention is considered a holistic approach for stroke rehabilitation because it allows participants to express their thoughts and emotions through the arts. The group environment also promotes mutual support among participants. The creative art-making process helps expand participants' creativity and imagination as well as promote a sense of aesthetic appreciation. Previous studies have shown the effectiveness of the arts-based intervention in managing stroke and its psychosocial-spiritual comorbidities. Nevertheless, a systematic study has not been conducted, including in young survivors. This trial plans to investigate the effectiveness of an expressive arts-based intervention on bio-psychosocial-spiritual outcomes in young Chinese stroke survivors. METHODS/DESIGN: A single-blind, two-arm cluster randomised control trial with a waitlist control design will be adopted. One hundred and fifty-four stroke survivors, aged 18-64 years with modified Rankin Scale scores of 1-4, will be screened and randomised to either an expressive arts-based intervention group or a treatment-as-usual waitlist control group. The intervention group will receive a 90-min session once a week for a total of 8 weeks. All participants will be assessed three times: at baseline, 8 weeks, and 8 months after the baseline. Study outcomes include measures of depression and anxiety, perceived stress, perceived social support, hope, spiritual well-being, quality of life, salivary cortisol, blood pressure, and heart rate. DISCUSSION: This study is expected to contribute to the current knowledge on the effectiveness of an arts-based intervention on the holistic wellness of young stroke survivors. The findings will help stroke survivors and healthcare professionals make better choices in selecting practices that will yield maximum benefits, satisfaction, adherence, and sustainability. In addition, the examination of the relationships between bio-psychosocial-spiritual variables will help contribute to the development of holistic care for the survivors. TRIAL REGISTRATION: ClinicalTrials.gov , NCT03729648 . Registered 31 October 2018 - Retrospectively registered, (329 words).

Association of subsequent falls with evidence of dual-task interference while walking in community-dwelling individuals after stroke.

OBJECTIVE: The aim of this study was to examine the fall predictive value of single-task walking tests and extent of interference observed in dual-task walking tests in ambulatory individuals post stroke. DESIGN: This is an observational study with prospective cohort. SETTING: The study was conducted at the university laboratory. PARTICIPANTS: A total of 91 community-dwelling individuals with chronic stroke participated in the study. MAIN OUTCOME MEASURES: Time required to complete a 10-m walk test with and without obstacle negotiation was measured in isolation and in conjunction with performance of a verbal fluency task (category naming). Fall incidence, circumstances, and related injuries were recorded by monthly telephone calls for 12 months. RESULTS: A total of 91 individuals (mean (SD) age = 62.7 (8.3) years; mean (SD) post-stroke duration = 8.8 (5.3) years) participated in the study; 29 (32%) of them reported at least one fall during the follow-up period, with a total of 71 fall episodes. There was a significant difference in obstacle-crossing time under single-task (mean difference = 8.3 seconds) and dual-task (mean difference = 7.4 seconds) conditions, and also the degree of interference in mobility performance (increased dual-task obstacle-crossing time relative to the single-task obstacle-crossing time; mean difference = 3.3%) between the fallers and the non-fallers (P < 0.05). After adjusting for the effects of other relevant factors, a greater degree of interference in mobility performance remained significantly associated with a decreased risk of falling (adjusted odds ratio = 0.951, 95% CI = 0.907-0.997, P = 0.037). CONCLUSION: The degree of mobility interference during dual-task obstacle-crossing was the most effective in predicting falls among all the single-task and dual-task walking measure parameters tested. This simple dual-task walking assessment has potential clinical utility in identifying people post stroke at high risk of future falls.

Cognitive-motor interference in walking after stroke: test-retest reliability and validity of dual-task walking assessments.

OBJECTIVE: To explore the reliability and validity of a series of dual-task mobility assessments among individuals post-stroke. DESIGN: Observational study with repeated measures. SETTING: University laboratory. PARTICIPANTS: Thirty community-dwelling individuals with chronic stroke. INTERVENTIONS: Not applicable. MAIN MEASURES: Each of the two mobility tasks (1-minute level-ground walking with and without obstacle-negotiation) was performed concurrently with each of the eight cognitive tasks (auditory Stroop test, serial subtraction, shopping list recall and category naming at two difficulty levels). Walking distance and obstacle hitting rate (OHR) indicated dual-task mobility performance. Number of correct responses (NCR) indicated cognitive performance. Reaction time was additionally measured for the auditory Stroop test. Construct validity was examined by correlations between the dual-task assessments. The dual-task assessments were repeated within 7-14 days for test-retest reliability. RESULTS: Excellent test-retest reliability in walking distance and OHR was found (intraclass correlation coefficient, ICC(3,1) = 0.891-0.984, P < 0.05). Moderate to excellent reliability was found in NCR and reaction time (ICC(3,1) = 0.480-0.911, P < 0.01). Correlations between walking distance were excellent ( rs = 0.840-0.985, P < 0.01). Correlations of NCR and reaction time between low- and high-level cognitive tasks were mostly moderate to excellent ( rs = 0.515-0.793, P < 0.01). Generally no significant correlations were found in NCR between the dual-task assessments with different cognitive domains. CONCLUSION: The dual-task walking assessments are reliable and valid for evaluating cognitive-motor interference in community-dwelling individuals post-stroke. The lack of correlations between the tasks of different cognitive domains indicates the need of using different cognitive domains in dual-task walking assessment post-stroke.

Dual-Task Exercise Reduces Cognitive-Motor Interference in Walking and Falls After Stroke.

Background and Purpose- Functional community ambulation requires the ability to perform mobility and cognitive task simultaneously (dual-tasking). This single-blinded randomized controlled study aimed to examine the effects of dual-task exercise in chronic stroke patients. Methods- Eighty-four chronic stroke patients (24 women; age, 61.2±6.4 years; time since stroke onset, 75.3±64.9 months) with mild to moderate motor impairment (Chedoke-McMaster leg motor score: median, 5; interquartile range, 4-6) were randomly allocated to the dual-task balance/mobility training group, single-task balance/mobility group, or upper-limb exercise (control) group. Each group exercised for three 60-minute sessions per week for 8 weeks. The dual-task interference effect was measured for the time to completion of 3 mobility tests (forward walking, timed-up-and-go, and obstacle crossing) and for the correct response rate during serial-3-subtractions and verbal fluency task. Secondary outcomes included the Activities-specific Balance Confidence Scale, Frenchay Activities Index, and Stroke-specific Quality of Life Scale. The above outcomes were measured at baseline, immediately after, and 8 weeks after training. Fall incidence was recorded for a 6-month period posttraining. Results- Only the dual-task group exhibited reduced dual-task interference in walking time posttraining (forward walking combined with verbal fluency [9.5%, P=0.014], forward walking with serial-3-subtractions [9.6%, P=0.035], and the timed-up-and-go with verbal fluency [16.8%, P=0.001]). The improvements in dual-task walking were largely maintained at the 8-week follow-up. The dual-task cognitive performance showed no significant changes. The dual-task program reduced the risk of falls and injurious falls by 25.0% (95% CI, 3.1%-46.9%; P=0.037) and 22.2% (95% CI, 4.0%-38.4%; P=0.023), respectively, during the 6-month follow-up period compared with controls. There was no significant effect on other secondary outcomes ( P>0.05). Conclusions- The dual-task program was effective in improving dual-task mobility, reducing falls and fall-related injuries in ambulatory chronic stroke patients with intact cognition. It had no significant effect on activity participation or quality of life. Clinical trial registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02270398.

Dual-task training effects on motor and cognitive functional abilities in individuals with stroke: a systematic review.

OBJECTIVE: This systematic review aimed to examine the effects of dual-task balance and mobility training in people with stroke. METHODS: An extensive electronic databases literature search was conducted using MEDLINE, PubMed, EBSCO, The Cochrane Library, Web of Science, SCOPUS, and Wiley Online Library. Randomized controlled studies that assessed the effects of dual-task training in stroke patients were included for the review (last search in December 2017). The methodological quality was evaluated using the Cochrane Collaboration recommendation, and level of evidence was determined according to the criteria described by the Oxford Center for Evidence-Based Medicine. RESULTS: About 13 articles involving 457 participants were included in this systematic review. All had substantial risk of bias and thus provided level IIb evidence only. Dual-task mobility training was found to induce more improvement in single-task walking function (standardized effect size = 0.14-2.24), when compared with single-task mobility training. Its effect on dual-task walking function was not consistent. Cognitive-motor balance training was effective in improving single-task balance function (standardized effect size = 0.27-1.82), but its effect on dual-task balance ability was not studied. The beneficial effect of dual-task training on cognitive function was provided by one study only and thus inconclusive. CONCLUSION: There is some evidence that dual-task training can improve single-task walking and balance function in individuals with stroke. However, any firm recommendation cannot be made due to the weak methodology of the studies reviewed.

Vitamin D status and cardiometabolic risk factors in young adults in Hong Kong: associations and implications.

BACKGROUND AND OBJECTIVES: Vitamin D deficiency is reportedly common, but we lack data from young adults. Such data are of interest because epidemiological data support vitamin D as a possible risk modulator for diabetes and cardiovascular ('cardiometabolic') disease. Our objectives were to assess vitamin D status (as plasma 25(OH)D concentration) and investigate associations between this and biomarkers of cardiometabolic disease risk in a group of still-healthy young adults in Hong Kong. METHODS AND STUDY DESIGN: In this observational study, fasting venous blood was collected from 196 (63 males, 133 females), young (18-26 years) non-smoking, nonobese, consenting adults in good general health. Plasma 25(OH)D was measured by LC-MS/MS. A panel of established cardiometabolic risk factors (HbA1c, plasma glucose, lipid profile, hsCRP) and blood pressure were also measured. RESULTS: Mean (SD) plasma 25(OH)D concentration was 42.1 (13.0), with range 15.7-86.8 nmol/L; 141/196 subjects (72%) had vitamin D deficiency (25(OH)D <50 nmol/L); 13/184 (6.6%) were severely deficient (<25 nmol/L). Inverse association was seen between 25(OH)D and fasting glucose (r=-0.18; p<0.05). Higher HbA1c and TC:HDL-C ratio and lower HDL-C were seen in those with plasma 25(OH)D <25 nmol/L (p<0.05). CONCLUSIONS: Vitamin D deficiency was highly prevalent and associated with poorer cardiometabolic risk profile in these young adults. Public health strategies for addressing vitamin D deficiency are needed urgently. These new data provide support for further study on vitamin D deficiency as a modifiable risk factor for cardiometabolic disease and the ameliorative effects of increased vitamin D intake on cardiometabolic disease risk profile of vitamin D-deficient young adults.

Transmissibility and waveform purity of whole-body vibrations in older adults.

BACKGROUND: This study examined the transmission power and waveform purity of vertical (synchronous) whole-body vibrations upon its propagation in the human body among older adults. METHODS: Forty community-dwelling older adults participated in the study (33 women; mean age: 60.3 (SD 5.7) years). Four vibration frequencies (25, 30, 35, 40Hz), two amplitudes (0.6 and 0.9mm), and six different postures were tested. Skin-mounted tri-axial accelerometers were placed at the medial malleolus, tibial tuberosity, greater trochanter, third lumbar vertebra, and forehead. The transmissibility of vibration was computed as the ratio of the root-mean-square-acceleration at different body sites to that of the platform. Signal purity was expressed by the percentage of total transmitted power within 1Hz of the nominal frequency delivered by the platform. FINDINGS: Vibration frequency and amplitude were inversely associated with transmissibility in all anatomical landmarks except the medial malleolus. Amplification of signals was noted at the medial malleolus in most testing conditions. The effect of posture on whole-body vibration transmission depends on its frequency and amplitude. In general, toe-standing led to the lowest transmissibility. Single-leg standing had the highest vibration transmission to the hip, while erect standing had the highest transmissibility to the head. The purity of waveform of the vibration signals was well conserved as the vibrations were transmitted from the feet to the upper body. INTERPRETATION: Whole-body vibration transmissibility was highly influenced by signal frequency, amplitude and posture. These parameters should be carefully considered when prescribing whole-body vibration to older adults.

Psychometric properties of dual-task balance and walking assessments for individuals with neurological conditions: A systematic review.

BACKGROUND: The ability of performing a balance or walking task in conjunction with a secondary cognitive or motor task, referred to as dual-task (DT) ability, is essential in daily living. While there is some evidence that DT performance is impaired in individuals with neurological conditions, using reliable and valid tools to measure DT performance is essential. This systematic review aimed to evaluate the psychometric properties of DT balance and walking assessments in individuals with different neurological conditions. METHODS: A systematic literature search was conducted using PubMed, CINAHL, MEDLINE, PsycINFO, SCOPUS, Web of Science, and Cochrane Library (last search done in April 2016). The methodological quality was rated using the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) checklist. RESULTS: Twenty-three articles involving individuals with stroke, Parkinson's disease, mild cognitive impairment, dementia, Alzheimer's disease, and multiple sclerosis were included. Outcomes derived from the walking tasks under DT condition generally demonstrated good reliability (correlation coefficient ≥0.75) across different neurological disorders, but their usefulness in distinguishing fallers from non-fallers was inconclusive. The reliability of outcomes derived from the cognitive/motor tasks and from the dual-task effect (DTE) (i.e., DT performance minus single-task performance) seemed to be lower but was understudied. The reliability of static or dynamic sitting/standing balance outcomes in DT condition was not assessed in any of the selected studies. CONCLUSIONS: The reliability of the outcomes derived from walking tasks was good. The psychometric properties of other DT outcomes need to be further investigated.

Effect of Whole-Body Vibration on Neuromuscular Activation of Leg Muscles During Dynamic Exercises in Individuals With Stroke.

Liao, L-R, and Pang, MYC. Effect of whole-body vibration on neuromuscular activation of leg muscles during dynamic exercises in individuals with stroke. J Strength Cond Res 31(7): 1954-1962, 2017-This study examined the leg muscle activity during exposure to different whole-body vibration (WBV) intensities while performing various dynamic exercises in patients with chronic stroke. Thirty patients with chronic stroke performed a series of dynamic exercises under 3 conditions: (a) low-intensity WBV (peak acceleration: 0.96 units of gravity of Earth [g]), (b) high-intensity WBV (1.61 g), and (c) no WBV. Neuromuscular activation was recorded with surface electromyography (EMG) on bilateral biceps femoris (BF), vastus lateralis, tibialis anterior (TA), and gastrocnemius (GS) in both legs and was reported as EMGrms (root mean square) normalized to % maximal voluntary contraction. The EMG amplitude of all tested muscles was significantly increased by adding WBV during dynamic exercise (p ≤ 0.05). The EMG amplitude of BF, TA, and GS during exposure to high-intensity WBV was significantly greater than low-intensity WBV (p ≤ 0.05). The increase in EMG amplitude caused by WBV was exercise dependent in GS and TA (p ≤ 0.05). The EMG response to WBV in GS and BF in the affected leg was significantly greater than the corresponding muscles in the unaffected leg (p ≤ 0.05). The extent of WBV-induced muscle activity was dependent on the dynamic exercise, WBV intensity, and muscle trained among patients with chronic stroke.

Reliability and Validity of Dual-Task Mobility Assessments in People with Chronic Stroke.

BACKGROUND: The ability to perform a cognitive task while walking simultaneously (dual-tasking) is important in real life. However, the psychometric properties of dual-task walking tests have not been well established in stroke. OBJECTIVE: To assess the test-retest reliability, concurrent and known-groups validity of various dual-task walking tests in people with chronic stroke. DESIGN: Observational measurement study with a test-retest design. METHODS: Eighty-eight individuals with chronic stroke participated. The testing protocol involved four walking tasks (walking forward at self-selected and maximal speed, walking backward at self-selected speed, and crossing over obstacles) performed simultaneously with each of the three attention-demanding tasks (verbal fluency, serial 3 subtractions or carrying a cup of water). For each dual-task condition, the time taken to complete the walking task, the correct response rate (CRR) of the cognitive task, and the dual-task effect (DTE) for the walking time and CRR were calculated. Forty-six of the participants were tested twice within 3-4 days to establish test-retest reliability. RESULTS: The walking time in various dual-task assessments demonstrated good to excellent reliability [Intraclass correlation coefficient (ICC2,1) = 0.70-0.93; relative minimal detectable change at 95% confidence level (MDC95%) = 29%-45%]. The reliability of the CRR (ICC2,1 = 0.58-0.81) and the DTE in walking time (ICC2,1 = 0.11-0.80) was more varied. The reliability of the DTE in CRR (ICC2,1 = -0.31-0.40) was poor to fair. The walking time and CRR obtained in various dual-task walking tests were moderately to strongly correlated with those of the dual-task Timed-up-and-Go test, thus demonstrating good concurrent validity. None of the tests could discriminate fallers (those who had sustained at least one fall in the past year) from non-fallers. LIMITATION: The results are generalizable to community-dwelling individuals with chronic stroke only. CONCLUSIONS: The walking time derived from the various dual-task assessments generally demonstrated good to excellent reliability, making them potentially useful in clinical practice and future research endeavors. However, the usefulness of these measurements in predicting falls needs to be further explored. Relatively low reliability was shown in the cognitive outcomes and DTE, which may not be preferred measurements for assessing dual-task performance.

Development and validation of the Chinese version of the Massachusetts General Hospital Acupuncture Sensation Scale: an exploratory and methodological study.

BACKGROUND: The Massachusetts General Hospital Acupuncture Sensation Scale (MASS) is a tool to measure needle sensations. The aims of the present study were to develop a Chinese version and to assess its psychometric properties. METHODS: This study was a methodological and exploratory study. The English version of the MASS was translated into Chinese using standardised translation procedures. Content validity was conducted by nine acupuncture experts. The prefinal Chinese version (C-MASS) was then administered to 30 acupuncture-naïve, healthy subjects. Electroacupuncture was performed on the right LI4 and LI11 acupoints for 30 min. A test-retest reliability measurement was administered 1-2 weeks later. Construct validity was examined by comparing results from C-MASS and the Short-Form McGill Pain Questionnaire (SF-MPQ). The construct validity was further assessed by the principle component analysis. RESULTS: C-MASS demonstrated a content validity ratio on relevance and importance from -0.04 to 1.00. Convergent validity was demonstrated by its significant association with the sensory dimension of SF-MPQ (γ=0.63, p<0.05). Discriminant validity was demonstrated by its low association with the affective dimension of SF-MPQ (γ=-0.3, p=0.111). A five-factor structure of C-MASS was established by factor analysis. C-MASS demonstrated good internal consistency (Cronbach's α=0.71) and test-retest reliability (intraclass correlation coefficient=0.92). Since the descriptor 'sharp pain' was not a valid needle sensation related to deqi, this was removed from C-MASS. We renamed the scale as the Modified MASS-Chinese version (C-MMASS). CONCLUSIONS: A 12-descriptor C-MMASS was established and shown to be a reliable and valid tool in reporting needle sensations associated with deqi among healthy young Chinese people.