Olfaction, ability to identify particular olfactory clusters and odors, and physical performance in community-dwelling older adults: The Yanai Study.

BACKGROUND: Olfactory dysfunction is associated with poor physical performance in older adults. However, it remains unknown whether the ability to identify particular olfactory clusters and/or odors is associated with physical performance in physically independent community-dwelling older adults. METHODS: This cross-sectional study included 130 community-dwelling older adults (70.1 ± 5.5 years). The Odor Stick Identification Test for Japanese people, consisting of 12 odors in four clusters (wood, grass, herb; sweet; spices; foul-smelling), was used to examine olfaction. Participants also completed physical performance tests (one leg standing with open eyes; aerobic capacity; lower muscle function: five-times chair stand [CS] and vertical jump; mobility: star walking and timed up and go [TUG]) and cognitive function tests. RESULTS: Worse overall olfaction was not significantly associated with any physical performance measure. Worse performance for identifying sweet odors and an inability to identify some specific odors (menthol and rose) were associated with worse mobility and/or lower muscle function-adjusted covariates. Moreover, an inability to identify menthol and rose was associated with worse TUG (odds ratio [OR]: 0.424; 95% confidence interval [CI]: 0.215-0.836), star walking (OR: 0.714; 95% CI: 0.506-0.976), CS (OR: 0.638; 95% CI: 0.470-0.864), and vertical jump (OR: 1.12; 95% CI: 1.001-1.24) performance, even when the analysis was adjusted to exclude menthol and rose score from the overall olfaction score (p < .05 for all). CONCLUSIONS: The current study may help to increase awareness of olfactory and physical dysfunction at an earlier stage among physically independent community-dwelling older adults.

[Fall risk assessment and knee extensor muscle activity in elderly people].

PURPOSE: The purpose of this study was to analyze relationships between the history of falls, tripping, sway, and knee extensor muscle strengths as a tool for fall risk assessment in elderly people. We examined effective fall prevention measures. METHODS: We investigated 102 elderly volunteers in the community. The subjects were classified according to history of falls, tripping, sway and 5 performance tests conducted to assess fall risk including Timed up-and-go test (TUG), Functional Reach test (FR), Hand grip and Reaction time (RT). In addition, the time serial data of the knee extensor muscle strength were acquired using a hand-held dynamometer. RESULTS: In comparison to the non-faller group, the faller group showed a significantly higher incident rate of tripping and sway. A frequency analysis using the Maximum Entropy Method revealed that the fallers group showed lower peak frequency (p=0.025). Also, the slope of the logarithmical spectrum was less steep in the fallers group (p=0.035). Also results from analysis of the peak force latency from the beginning of measurement to 50%, 80%, and 100% muscle strength, also showed that the faller group took more time for maximal voluntary contraction. CONCLUSIONS: The frequency analysis of the time series date of peak force latency of knee extensor muscle strength revealed that the muscle activity differs in faller compared to non-fallers. This study suggested that knee extensor muscle isometric performance could possibly be used as a new tool for fall risk assessment. We concluded that exercises to raise maximal muscle strength and muscle response speed are useful for the prevention of falls.