Cognitive impairment is correlated with olfactory identification deficits in older Japanese adults: A cross‐sectional study using objective and subjective olfactory measures. Issue 11 (22nd September 2022)

• Record Type: Journal Article
• Authors: Suzuki, Hirokazu; Sugiura, Saiko; Nakashima, Tsutomu; Teranishi, Masaaki; Shimono, Mariko; Murotani, Kenta; Sakurai, Takashi; Uchida, Yasue; Saji, Naoki
• Is Part Of: Geriatrics and gerontology international. Volume 22:Issue 11(2022)
• Page Start: 924
• Page End: 929
• Publication Date: 2022-09-22
• Subjects: dementia -- hyposmia -- mild cognitive impairment -- olfactory impairment -- odor; Geriatrics -- Periodicals; Gerontology -- Periodicals; Geriatrics -- Japan -- Periodicals; Gerontology -- Japan -- Periodicals; 618.97
• DOI: 10.1111/ggi.14483
• Languages: English
• ISSNs: 1444-1586

Abstract

Abstract : Aim: Olfactory impairment is associated with cognitive impairment. However, differences between subjective and objective olfactory impairment measurements in older adults and their relationship with cognitive impairment are unclear. Methods: We assessed the relationship between cognitive and olfactory impairments via a single‐center observational study in 2020. Forty‐seven individuals who visited our memory clinic were enrolled and asked to complete objective and subjective olfactory tests. Participants had dementia, mild cognitive impairment, or normal cognition. We administered the Open Essence (a simple card‐type odor identification test) and self‐administered odor questionnaire to assess objective and subjective olfaction, respectively, and the Mini‐Mental State Examination to assess cognitive function. Results: Older age was related to decreased Open Essence scores ( P < 0.001). Compared with the mild cognitive impairment and normal cognition groups, the dementia group had significantly lower Open Essence scores ( P < 0.001). Cognitive impairment was also associated with decreased Open Essence scores after adjusting for age, sex, and education ( P < 0.001). Participants with dementia did not obtain lower self‐administered odor questionnaire scores than those with normal cognition, and they tended to be unaware of their olfactory impairment. Conclusion: Open Essence scores significantly decreased according to the degree of cognitive impairment. Participants with dementia were unaware of their olfactory impairment, as indicated by odor questionnaire scores. Objective and subjective scores of olfaction differed in participants with dementia. Concomitant assessment of objective and subjective olfaction is useful to screen older adults with both olfactory and cognitive impairments. Geriatr Gerontol Int 2022; 22: 924–929 . Abstract : We assessed the relationship between cognitive and olfactory impairments in older adults via a single‐center observational study. Open Essence (a simple card‐type odor identification test) scores significantly decreased according to the degree of cognitive impairment; however, participants with dementia were unaware of their olfactory impairment, as indicated by odor questionnaire scores. Concomitant assessment of objective and subjective olfaction is useful to screen older adults with both olfactory and cognitive impairments.