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Updated: Sep 9, 2025
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Olfactory Assays for Mouse Models of Neurodegenerative Disease
Published on: August 25, 2014
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Olfactory function is longitudinally associated with semantic fluency in Parkinson's disease: a cohort study.
Dareia S Roos1,2, Henk W Berendse3,4, Richard L Doty5,6
1Department of Neurology, Amsterdam UMC Location Vrije Universiteit Amsterdam, de Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands. d.roos@amsterdamumc.nl.
Journal of Neurology
|September 2, 2025
Summary
Olfactory dysfunction in Parkinson's disease (PD) is linked to worsening cognitive function over time. Early smell tests may predict future cognitive decline, especially in semantic fluency.
Area of Science:
- Neuroscience
- Neurology
- Gerontology
Background:
- Olfactory dysfunction is a common, early, and progressive symptom in Parkinson's disease (PD).
- The longitudinal association between olfactory decline and the progression of non-motor symptoms in PD is not fully understood.
Purpose of the Study:
- To investigate the longitudinal relationship between olfactory function and (non-)motor symptoms in PD patients.
- To specifically examine the association between olfactory decline and cognitive deterioration over a ten-year period.
Main Methods:
- Ninety PD patients underwent assessment at baseline and after ten years.
- Olfactory function was measured using the University of Pennsylvania Smell Identification Test (UPSIT®).
- Non-motor symptoms, including global cognitive function (MMSE) and specific cognitive tests (semantic fluency), were evaluated.
Main Results:
- A decrease in UPSIT® scores correlated with a decline in MMSE scores and worsening semantic fluency.
- Baseline UPSIT® scores were associated with MMSE performance and semantic fluency at the ten-year follow-up.
Conclusions:
- Declining olfactory function in PD is longitudinally associated with worsening global cognitive function, particularly semantic fluency.
- Baseline olfactory function may predict future cognitive decline in PD patients, especially in the semantic domain.
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