Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Dec 20:9:e12656.
doi: 10.7717/peerj.12656. eCollection 2021.

Utility of olfactory identification test for screening of cognitive dysfunction in community-dwelling older adults

Affiliations

Utility of olfactory identification test for screening of cognitive dysfunction in community-dwelling older adults

Satoshi Nogi et al. PeerJ. .

Abstract

Background: There is a need for a large-scale screening test that can be used to detect dementia in older individuals at an early stage. Olfactory identification deficits have been shown to occur in the early stages of dementia, indicating their usefulness in screening tests. This study investigated the utility of an olfactory identification test as a screening test for mild cognitive dysfunction in community-dwelling older people.

Methods: The subjects were city-dwelling individuals aged over 65 years but under 85 years who had not been diagnosed with dementia or mild cognitive impairment. The Japanese version of the Mild Cognitive Impairment Screen was used to evaluate cognitive function. Based on the results, the subjects were divided into two groups: healthy group and cognitively impaired group. Olfactory identification abilities based on the Japanese version of the University of Pennsylvania Smell Identification Test were compared between the groups.

Results: There were 182 participants in total: 77 in the healthy group and 105 in the cognitively impaired group. The mean olfactory identification test score of the cognitively impaired group was significantly lower than that of the healthy group. The cognitive impairment test score was significantly correlated with the olfactory identification test score.

Conclusions: Cross-sectional olfactory identification deficits at baseline in community-dwelling older adults reflected cognitive dysfunction. Assessing olfactory identification ability might be useful as a screening test for mild cognitive dysfunction in community-dwelling older people.

Keywords: Community-dwelling older adults; Dementia; Early diagnosis; Mass screening; Olfaction disorders; Olfactory identification.

PubMed Disclaimer

Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Figure 1
Figure 1. Differences in median scores between healthy and cognitively impaired groups.
Abbreviations: UPSIT score, University of Pennsylvania Smell Identification Test score.
Figure 2
Figure 2. Correlation between MPI and UPSIT scores of all participants.
Abbreviations: MPI, Memory Performance Index; UPSIT score, University of Pennsylvania Smell Identification Test score.

References

    1. Alves J, Petrosyan A, Magalhaes R. Olfactory dysfunction in dementia. World Journal of Clinical Cases. 2014;2(11):661–667. doi: 10.12998/wjcc.v2.i11.661. - DOI - PMC - PubMed
    1. Attems J, Walker L, Jellinger KA. Olfactory bulb involvement in neurodegenerative diseases. Acta Neuropathologica. 2014;127(4):459–475. doi: 10.1007/s00401-014-1261-7. - DOI - PubMed
    1. Bohnen NI, Gedela S, Kuwabara H, Constantine GM, Mathis CA, Studenski SA, Moore RY. Selective hyposmia and nigrostriatal dopaminergic denervation in Parkinson’s disease. Journal of Neurology. 2007;254(1):84–90. doi: 10.1007/s00415-006-0284-y. - DOI - PubMed
    1. Callahan CM, Hendrie HC, Tierney WM. Documentation and evaluation of cognitive impairment in elderly primary care patients. Annals of Internal Medicine. 1995;122(6):422–429. doi: 10.7326/0003-4819-122-6-199503150-00004. - DOI - PubMed
    1. Cho A, Sugimura M, Nakano S, Yamada T. Current topics in management: the Japanese MCI screen for early detection of Alzheimer’s disease and related disorders. American Journal of Alzheimer’s Disease & Other Dementiasr. 2008;23(2):162–166. doi: 10.1177/1533317507312624. - DOI - PMC - PubMed

LinkOut - more resources