Related Experiment Video
Updated: May 26, 2025
10:42
A Free-breathing fMRI Method to Study Human Olfactory Function
Published on: July 30, 2017
9.6K
Characterizing the olfaction and dementia association in the community-based ARIC study
Srishti Shrestha1, Xiaoqian Zhu1, Anna M Kucharska-Newton2
1The Memory Impairment and Neurodegenerative Dementia (MIND) Center, University of Mississippi Medical Center, Jackson, Mississippi, USA.
Alzheimer'S & Dementia : the Journal of the Alzheimer'S Association
|February 24, 2025
Summary
Reduced sense of smell is linked to a higher risk of dementia. This association is stronger with persistent smell loss or significant decline over time, regardless of age, race, sex, or APOE ε4 status.
Area of Science:
- Neuroscience
- Gerontology
- Epidemiology
Background:
- Olfactory dysfunction is an early sign of neurodegenerative diseases.
- Limited research exists on the detailed association between olfaction and dementia across diverse populations.
Purpose of the Study:
- To investigate the association of olfactory status and olfactory change with incident dementia.
- To examine these associations across various sociodemographic subgroups and APOE ε4 carrier status.
Main Methods:
- Analysis of data from the Atherosclerosis Risk in Communities (ARIC) study.
- Examined one-time olfactory status and 5-year olfactory change in relation to dementia incidence.
- Stratified analyses by age, race, sex, and apolipoprotein E (APOE) ε4 status.
Main Results:
- Moderate olfaction, hyposmia, and anosmia were all associated with increased dementia risk.
- Associations remained consistent across age, race, sex, and APOE ε4 subgroups.
- Persistent anosmia and olfactory decline over time showed the strongest dementia risk.
Conclusions:
- Olfactory impairment is a significant risk factor for incident dementia.
- The association is robust across diverse populations and genetic backgrounds.
- Monitoring olfactory function may aid in early dementia risk assessment.
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