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

Abstract

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. This cross-sectional study included 130 community-dwelling older adults (70.1±5.5years). 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. 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). The current study may help to increase awareness of olfactory and physical dysfunction at an earlier stage among physically independent community-dwelling older adults.