Environment and medication use influence olfactory abilities of older adults

Age-associated changes in eating behavior and nutritional status are often caused by changes in olfactory perception.

This study determined the relative contribution of medication use and environmental risk to age-associated change in olfaction.

Fifty participants aged 50-96 (M = 70.4) in two groups (environmentally at-risk and low-risk) were administered a set of four olfactory tasks, WAIS Vocabulary, MMSE, and demographic questionnaires. Environmental risk was defined as having worked in places where exposure to caustic fumes (e.g., formaldehyde, toluene, etc.) was common and long-term. Olfactory tasks included detection thresholds for phenethyl alcohol (PEA; assesses olfactory function) and menthol (assesses olfactory and trigeminal function); odor recognition in a forced-choice paradigm; odor difference discrimination; and odor identification with supplied names.

The high-risk group had significantly higher thresholds for PEA, and significant within-group variability for menthol. Medication usage and cognitive status were significantly associated with odor recognition. Only medication was strongly associated with the odor discrimination task. Medication usage, environmental risk, and age in order were found to be the greatest risk factors for odor identification.

These results highlight the need to carefully consider environmental and pharmacological effects in age-associated sensory tasks.