Environmental hazards as risk factors for trips and slips at home among Japanese older people: A pilot study toward the development of a self-assessment tool for the home environment.

AIM: Housing structures differ according to the local culture, climate, and lifestyle, and these unique characteristics usually act as potential hazards for falls, trips, and slips. The purpose of this study was to identify environmental hazards in a Japanese house and their association with falls, trips, and slips among older people. METHODS: A total of 97 older people aged ≥75 years were included in this cross-sectional study. The number of environmental hazards was measured using a 46-item tool designed specifically for this study, and the associations of environmental hazards with falls, trips, and slips were analyzed using univariate and multivariate logistic regressions. RESULTS: All houses had at least one environmental hazard, and 3-30 environmental hazards were identified. Although the number of environmental hazards was not associated with falls experienced during the past 6 months, a greater number of environmental hazards at home was correlated with the daily experience of trips and slips (odds ratio [OR]: 1.10; 95% confidence interval [CI]: 1.02-1.18). The association remained significant even after adjusting for demographic characteristics and other fall risk factors (OR: 1.11; 95% CI: 1.02-1.21). CONCLUSION: We found that Japanese housing structures had unique environmental hazards that might cause trips and slips in older people. Appropriate housing assessments and modifications may help to promote aging-in-place among older people. Geriatr Gerontol Int 2022; 22: 305-310.

Concurrent validity of the step time and walking speed obtained from the smartphone application CareCoaching in independent, community-dwelling older adults.

[Purpose] In this study, we verified the validity of the step time and walking speed obtained from the smartphone gait analysis application CareCoaching. [Participants and Methods] The participants were 66 independent, community-dwelling adults aged 65 years or older who performed a 10-m walking test twice each under preferred- and slow-speed conditions. We concurrently measured gait motions using CareCoaching and the OptoGait system for reference data. Both systems compute walking speed and step time as gait parameters. We examined the concurrent validity of these parameters by using intra-class correlation coefficients (ICCs) and limits of agreement (LOAs) with Bland-Altman analyses. [Results] In the preferred walking speed condition, the ICCs of walking speed and step times between the CareCoaching and the OptoGait system were 0.67 and 0.93, respectively. In the slow walking speed condition, the ICCs for walking speed and step time were 0.78 and 0.97, respectively. In addition, the LOAs for step time were -0.0941 to 0.1160 for preferred walking speed and -0.0596 to 0.0883 for slow walking speed. The LOAs for walking speed were -0.4158 to 0.0568 for preferred walking speed and -0.3348 to 0.0523 for slow walking speed. [Conclusion] CareCoaching showed excellent agreement for step time and moderate-to-good agreement for walking speed in independent, community-dwelling older adults.

Difference in Physiological Components of VO2 Max During Incremental and Constant Exercise Protocols for the Cardiopulmonary Exercise Test.

[Purpose] VO2 is expressed as the product of cardiac output and O2 extraction by the Fick equation. During the incremental exercise test and constant high-intensity exercise test, VO2 results in the attainment of maximal O2 uptake at exhaustion. However, the differences in the physiological components, cardiac output and muscle O2 extraction, have not been fully elucidated. We tested the hypothesis that constant exercise would result in higher O2 extraction than incremental exercise at exhaustion. [Subjects] Twenty-five subjects performed incremental exercise and constant exercise at 80% of their peak work rate. [Methods] Ventilatory, cardiovascular, and muscle oxygenation responses were measured using a gas analyzer, Finapres, and near-infrared spectroscopy, respectively. [Results] VO2 was not significantly different between the incremental exercise and constant exercise. However, cardiac output and muscle O2 saturation were significantly lower for the constant exercise than the incremental exercise at the end of exercise. [Conclusion] These findings indicate that if both tests produce a similar VO2 value, the VO2 in incremental exercise would have a higher ratio of cardiac output than constant exercise, and VO2 in constant exercise would have a higher ratio of O2 extraction than incremental exercise at the end of exercise.

Muscle oxygen extraction is higher during constant work exercise than during incremental ramp exercise.

A cardiopulmonary exercise test (CPX) can provide objective measures of exercise capacity. Specifically, incremental ramp exercise (IRE) and constant work-rate exercise (CWE) protocols are frequently used in clinical practice and for research. The CWE endurance time has shown larger increases than other indexes assessed by IRE after rehabilitation intervention. Muscle oxygen extraction is one of the important physiological factors of exercise capacity; however, the differences in muscle oxygen kinetics between IRE and CWE remain unclear. The purpose of this study was to compare the muscle oxygen kinetics during IRE and CWE. Each of the 15 participants performed IRE and CWE to exhaustion on a cycle ergometer. Ventilatory and muscle deoxygenation responses were measured during the tests; muscle deoxygenation was determined using near-infrared spectroscopy. No differences in oxygen uptake and heart rate were observed between the two tests. A comparison of the muscle deoxygenation kinetics between the two tests indicated significantly greater deoxygenation during the CWE than during the IRE at all time points (p < 0.05). The muscle deoxygenation kinetics, as percentages of maximal oxygen uptake (VO2max), were higher during CWE than during IRE, except at 80% of VO2max (p < 0.05). These results suggest that skeletal muscle during CWE extracts oxygen at a rate comparable to that during IRE, and that exercise capacity assessed using CWE might be linked to a higher overall O2 extraction. The fact that endurance time during CWE is more sensitive to rehabilitation intervention may be due to improvements in muscle oxygen extraction.