Shu Nishiguchi

Reliability and Validity of Gait Analysis by Android-Based Smartphone

Smartphones are very common devices in daily life that have a built-in tri-axial accelerometer. Similar to previously developed accelerometers, smartphones can be used to assess gait patterns. However, few gait analyses have been performed using smartphones, and their reliability and validity have not been evaluated yet. The purpose of this study was to evaluate the reliability and validity of a smartphone accelerometer. Thirty healthy young adults participated in this study. They walked 20 m at their preferred speeds, and their trunk accelerations were measured using a smartphone and a tri-axial accelerometer that was secured over the L3 spinous process. We developed a gait analysis application and installed it in the smartphone to measure the acceleration. After signal processing, we calculated the gait parameters of each measurement terminal: peak frequency (PF), root mean square (RMS), autocorrelation peak (AC), and coefficient of variance (CV) of the acceleration peak intervals. Remarkable consistency was observed in the test-retest reliability of all the gait parameter results obtained by the smartphone (p<0.001). All the gait parameter results obtained by the smartphone showed statistically significant and considerable correlations with the same parameter results obtained by the tri-axial accelerometer (PF r=0.99, RMS r=0.89, AC r=0.85, CV r=0.82; p<0.01). Our study indicates that the smartphone with gait analysis application used in this study has the capacity to quantify gait parameters with a degree of accuracy that is comparable to that of the tri-axial accelerometer.

A 12-Week Physical and Cognitive Exercise Program Can Improve Cognitive Function and Neural Efficiency in Community-Dwelling Older Adults: A Randomized Controlled Trial

To investigate whether a 12‐week physical and cognitive exercise program can improve cognitive function and brain activation efficiency in community‐dwelling older adults.

Differential Association of Frailty With Cognitive Decline and Sarcopenia in Community-Dwelling Older Adults

OBJECTIVES Frailty in older adults is a serious problem because of various adverse health outcomes in many countries with aging populations, such as Japan. The purpose of this study was to determine whether frailty and pre-frailty are associated with cognitive decline and sarcopenia in community-dwelling older adults. DESIGN This is a cross-sectional study. SETTING Japan. PARTICIPANTS The participants were 273 Japanese community-dwelling older women aged 65 years and older. MEASUREMENTS We used the frailty criteria developed by the Cardiovascular Health Study to define physical frailty. We divided the cohort into nonfrail, prefrail, and frail according to frailty scores. Cognitive decline and memory decline were defined by using the Mini-Mental State Examination and Scenery Picture Memory Test, respectively. Sarcopenia was defined according to the diagnostic algorithm recommended by the Asian Working Group for Sarcopenia. RESULTS In the multivariate logistic regression analysis by using non-frail participants as the reference, pre-frail elderly individuals were significantly more likely to have sarcopenia than non-frail elderly individuals [odds ratio (OR): 2.77, 95% confidence interval (CI): 1.05-9.26], but not cognitive decline or memory decline. Frail elderly individuals were significantly more likely to have cognitive decline (OR: 5.76, 95% CI: 1.20-27.6), memory decline (OR: 5.53, 95% CI: 1.64-18.7) and sarcopenia (OR: 19.1, 95% CI: 3.73-98.0) than non-frail elderly individuals. CONCLUSIONS Sarcopenia was associated with pre-frailty and frailty, whereas cognitive decline was associated only with frailty.

Relationship between depression and risk of malnutrition among community-dwelling young-old and old-old elderly people

Objectives: This study explores the association between nutritional status and depression among healthy community-dwelling young-old (aged 65–74) and old-old elderly (aged 75 and older). Method: A cross-sectional design was implemented. A total of 274 community-dwelling older individuals (142 young-old; 132 old-old) were assessed using the Geriatric Depression Scale (GDS), Mini-Nutritional Assessment Short-Form (MNA-SF) and Life-Space Assessment. Logistic regression analysis was used to determine if depression was independently associated with risk of malnutrition, stratified by age (young-old vs. old-old). Results: In the logistic regression model for young-old, being at risk of malnutrition (MNA-SF (≦11) was strongly associated with depression (GDS (≧5;) (likelihood ratio ν = 6.26; 95% confidence interval [CI]: 1.91–20.49). In contrast, in the old-old group, the model was not statistically significant. Conclusion: Depression and nutritional status were strongly correlated in young-old but not in old-old community-dwelling elderly. This study reveals that not only the factors correlated with but also the symptoms of depression may vary among different age stratifications of the elderly.

Effect of a Kinect-Based Exercise Game on Improving Executive Cognitive Performance in Community-Dwelling Elderly: Case Control Study

Decrease of Dual-Task (DT) ability is known to be one of fall-risk factors. We developed a new game concept, Dual-Task Tai Chi (DTTC), using Kinect (Microsoft Co.), a motion-capture device, and demonstrated that the DTTC test can quantitatively evaluate various functions that are known risk factors for falling in elderly adults. Moreover, DT training has been attracting attention as a way to improve balance and DT ability. However, only a few studies have reported that it improves cognitive performance. Therefore, the purpose of this study was to demonstrate whether or not a 12-week program of DTTC training would effectively improve cognitive functions. A total of 41 elderly individuals (training group: n = 26, control group: n = 15) participated in this study and their cognitive functions were assessed before and after DTTC training. Significant differences were observed between the two groups with significant group x time interactions for the executive cognitive function measure: t:. trail-making test (part Bpart A) (p <; 0.05). The results suggest that DTTC training is effective for improving executive cognitive functions.

Effect of physical activity on memory function in older adults with mild Alzheimer's disease and mild cognitive impairment

It is very important to maintain cognitive function in patients with mild cognitive disorder. The aim of the present study was to determine whether the amount of physical activity is associated with memory function in older adults with mild cognitive disorder.

Multitarget stepping program in combination with a standardized multicomponent exercise program can prevent falls in community-dwelling older adults: a randomized, controlled trial.

To investigate the effects of a twice‐weekly multitarget stepping (MTS) task combined with a multicomponent exercise program on stepping accuracy, gaze behavior, fall risk factors, and fall rates.

Chronic kidney disease (CKD) is an independent risk factor for long-term care insurance (LTCI) need certification among older Japanese adults: A two-year prospective cohort study

CKD is associated with impairments in health status, physical function, and frailty. The aim of the current prospective cohort study was to determine whether CKD predicted new LTCI need certification among community-dwelling older Japanese adults. This was a prospective cohort study. We analyzed the cohort data from a prospective study, The Japan Multicenter Aging Cohort for Care Prevention (J-MACC). We followed 8063 elderly adults for 2 years, and we analyzed the relationship between CKD and LTCI need. The outcome studied was new certification for LTCI service need during a 2-year period. We measured serum creatinine (the estimated glomerular filtration rate; eGFR), serum albumin, frailty checklist scores, and body mass index. During the 2-year follow-up, 536 subjects (6.6%) were newly certified as needing LTCI services. We stratified the cohort according to eGFR quartile and performed multivariate analyses using an eGFR value of 71.4-83.6 ml/min/1.73 m(2) as a reference. We found that subjects with eGFR values <60.0 ml/min/1.73 m(2) had a significantly elevated risk of LTCI service need (adjusted hazard ratio: 1.44 [95% CI 1.12-1.86]). Our results indicate that CKD is independently associated with new LTCI service need certification and is an important marker of frailty in older adults.

Development of measurement system for task oriented step tracking using laser range finder.

BackgroundAvoiding a fall requires fast and appropriate step responses, stepping speed as a fall risk indicator has only been assessed in older adults. We have developed a new measurement system that applies a laser range finder to assess temporal and spatial parameters of stepping performance such as step speed, length, and accuracy. This measurement system has higher portability, lower cost, and can analyze a larger number of temporal and spatial parameters than existing measurement systems. The aim of this study was to quantify the system for measuring reaction time and stride duration by compared to that obtained using a force platform.MethodsTen healthy young adults performed steps in response to visual cues. The measurement system applied a laser range finder to measure the position and velocity of the center of each leg and of both legs.We applied the developed measurement system to the rhythmic stepping exercise and measured reaction time and stride duration. In addition, the foot-off time and foot-contact time were quantified using the measurement system, and compared to the foot-off time and foot-contact time quantified using a force platform.ResultsWe confirmed that the measurement system can detect where a participant stood and measured reaction time and stride duration.Remarkable consistency was observed in the test-retest reliability of the foot-off time and foot-contact time quantified by the measurement system (p < 0.001). The foot-off time and foot-contact time quantified by the measurement system were highly correlated with the foot-off time and foot-contact time quantified by the force platform (reaction time: r = 0.997, stride duration: r = 0.879; p < 0.001).ConclusionsThe new measurement system provided a valid measure of temporal step parameters in young healthy adults.The validity of the system to measure reaction time and stride duration was evaluated, and confirmed by applying to the rhythmic stepping exercise.

Efficacy of an Exercise Game Based on Kinect in Improving Physical Performances of Fall Risk Factors in Community-Dwelling Older Adults

OBJECTIVE The purpose of this study was to demonstrate whether a 12-week program of training with dual-task Tai Chi (DTTC), which is a new concept game we developed using Kinect (Microsoft, Redmond, WA), would be effective in improving physical functions of fall risk factors. MATERIALS AND METHODS This study examined balance, muscle strength, locomotive ability, and dual-task ability in community-dwelling older adults (75.4±6.3 years) before and after 12 weeks of DTTC training (training group [TG]; n=32) or standardized training (control group [CG]; n=41). Primary end points were based on the difference in physical functions between the TG and the CG. RESULTS Significant differences were observed between the two groups with significant group×time interaction for the following physical function measures: timed up-and-go (TUG) (P<0.01), one-leg standing (OLS) (P<0.05), and 5 chair stand (5-CS) (P<0.05). There were no significant differences among the other measures: 10-m walking time under standard conditions, manual-task conditions, and cognitive-task conditions, 10-m maximal walking time, and Functional Reach test scores. Thus, the scores of TUG, OLS, and 5-CS in the TG improved significantly with DTTC training compared with the CG. CONCLUSIONS The results suggest that the DTTC training is effective in improving balance ability and mobility, which are risk factors for falls.