Odor Detection Thresholds in a Population of Older Adults

Objectives/Hypothesis: To measure odor detection thresholds and associated nasal and behavioral factors in an older adult population. Study Design: Cross-sectional cohort study. Methods: Odor detection thresholds were obtained using an automated olfactometer on 832 participants, aged 68 to 99 (mean age=77) years in the 21-year (2013-2016) follow-up visit of the Epidemiology of Hearing Loss Study. Results: The mean odor detection threshold (ODT) score was 8.2 (range=1-13; standard deviation=2.54), corresponding to an n-butanol concentration of slightly less than 0.03%. Older participants were significantly more likely to have lower (worse) ODT scores than younger participants (P<. 001). There were no significant differences in mean ODT scores between men and women. Older age was significantly associated with worse performance in multivariable regression models, and exercising at least once per week was associated with reduced odds of having a low (<5) ODT score. Cognitive impairment was also associated with poor performance, whereas a history of allergies or a deviated septum was associated with better performance. Conclusions: Odor detection threshold scores were worse in older age groups but similar between men and women in this large population of older adults. Regular exercise was associated with better odor detection thresholds, adding to the evidence that decline in olfactory function with age may be partly preventable.