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A Free-breathing fMRI Method to Study Human Olfactory Function
Published on: July 30, 2017
Olfactory dysfunction is associated with subjective memory complaints in community-dwelling elderly individuals
Hamid R Sohrabi1, Kristyn A Bates, Mark Rodrigues
1The School of Psychiatry and Clinical Neuroscience, University of Western Australia, Crawley, WA, Australia.
Journal of Alzheimer'S Disease : JAD
|June 5, 2009
Summary
Olfactory dysfunction, particularly impaired smell discrimination and identification, predicts memory complaints in older adults. This suggests smell tests may help identify individuals at risk for Alzheimer's disease and cognitive decline.
Area of Science:
- Neuroscience
- Gerontology
- Olfactory Research
Background:
- Olfactory dysfunction is linked to Alzheimer's disease (AD) progression.
- Subjective memory complaints (SMCs) may indicate increased AD risk but are also associated with other factors like depression.
- Identifying reliable early markers for SMCs in the elderly is crucial for timely intervention.
Purpose of the Study:
- To investigate the predictive value of olfactory function for subjective memory complaints in community-dwelling elderly individuals.
- To determine if olfactory symptoms are more significant predictors of memory complaints than depression or other factors.
- To explore the relationship between olfactory capacities (threshold, discrimination, identification) and SMCs.
Main Methods:
- A cohort of 144 elderly volunteers (aged 50-86) was assessed.
- Olfactory capacities, subjective memory complaints, depressive symptoms, and cognitive functions were evaluated.
- Statistical analyses were performed to identify significant associations between olfactory function and memory complaints.
Main Results:
- SMCs were significantly associated with olfactory discrimination and identification, but not olfactory threshold.
- Both olfactory function and depressive symptoms were significantly linked to SMCs.
- Individuals reporting memory complaints exhibited poorer overall olfactory functioning compared to non-complainers.
Conclusions:
- Olfactory capacity, specifically discrimination and identification, serves as a potential biomarker for identifying elderly individuals with memory complaints.
- These findings highlight the importance of olfactory assessment in detecting early signs of cognitive decline and Alzheimer's disease risk.
- Olfactory testing may aid in the early identification of at-risk populations for targeted interventions.
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