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Updated: Jun 13, 2026
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Olfactory Assays for Mouse Models of Neurodegenerative Disease
Published on: August 25, 2014
Olfactory function and Parkinson's disease in Southern Brazil
Ricardo Santin1, Vicente Faraon Fonseca, Cristina Birlen Bleil
1Movement Disorders Outpatient Clinics, Santa Casa de Porto Alegre, RS, Brazil.
Arquivos De Neuro-Psiquiatria
|May 14, 2010
Summary
Idiopathic Parkinson disease (IPD) patients show impaired sense of smell. Early-onset PD (EOPD) patients retain better olfactory function than late-onset PD (LOPD) patients.
Area of Science:
- Neurology
- Olfactory Neuroscience
Background:
- Idiopathic Parkinson disease (IPD) diagnosis traditionally relies on motor signs.
- Non-motor symptoms, including olfactory dysfunction, are prevalent in IPD and can aid diagnosis.
Purpose of the Study:
- To assess and compare olfactory function in Brazilian individuals with early-onset PD (EOPD), late-onset PD (LOPD), and healthy controls.
- To utilize the Sniffin' Sticks odor-identification test (SST) for evaluating olfactory performance.
Main Methods:
- A study involving 70 IPD patients (19 EOPD, 51 LOPD) and 70 matched healthy controls.
- Exclusion criteria included dementia and pre-existing smell loss.
- Olfactory function was measured using the Sniffin' Sticks odor-identification test (SST).
Main Results:
- Significant differences in SST scores were observed across all groups (p<0.001) after adjusting for covariates.
- Control group: 12.0 ± 0.3
- EOPD group: 8.3 ± 0.7
- LOPD group: 6.7 ± 0.4
Conclusions:
- Both EOPD and LOPD patients exhibit olfactory impairments compared to controls.
- EOPD patients demonstrate a better sense of smell compared to LOPD patients.
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