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Updated: Jun 23, 2026
11:40
Quantitative Autonomic Testing
Published on: July 19, 2011
Hyposmia in pure autonomic failure.
L Silveira-Moriyama1, C Mathias, L Mason
1Reta Lila Weston Institute of Neurological Studies and Queen Square Brain Bank for Neurological Diseases, UCL Institute of Neurology, London, UK.
Neurology
|May 13, 2009
Summary
Hyposmia, or impaired sense of smell, is less common in pure autonomic failure (PAF) than in Parkinson disease (PD). This study compared smell identification in patients with PAF, PD, multiple system atrophy (MSA), and controls.
Area of Science:
- Neuroscience
- Neurology
- Olfactory Research
Background:
- Parkinson disease (PD), multiple system atrophy (MSA), and pure autonomic failure (PAF) share dysautonomia and alpha-synuclein pathology.
- Hyposmia (impaired smell) and olfactory pathway pathology are recognized features of PD and MSA.
- The prevalence and severity of olfactory dysfunction in PAF remain less understood compared to PD and MSA.
Purpose of the Study:
- To investigate and compare odor identification abilities in patients with pure autonomic failure (PAF).
- To assess whether hyposmia is a characteristic feature of PAF.
- To compare olfactory function in PAF patients with those diagnosed with Parkinson disease (PD), multiple system atrophy (MSA), and healthy controls.
Main Methods:
- Utilized the University of Pennsylvania Smell Identification Test (UPSIT) to quantify odor identification.
- Evaluated 16 patients with PAF, 14 with MSA, 191 with PD, and 145 control subjects.
- Employed multiple linear regression analysis, adjusting for age, sex, and smoking habits, to determine disease-specific effects on UPSIT scores.
Main Results:
- Control subjects exhibited significantly higher UPSIT scores compared to both PAF and MSA patients.
- Parkinson disease (PD) patients demonstrated lower UPSIT scores than both PAF and MSA patients.
- No significant difference in UPSIT scores was observed between patients with MSA and PAF after adjusting for covariates.
Conclusions:
- Hyposmia may be present in pure autonomic failure (PAF), but it appears to be less severe than in Parkinson disease (PD).
- The findings suggest a differential impact of these alpha-synucleinopathies on olfactory pathways.
- Further investigation into the olfactory system's pathology in pure autonomic failure (PAF) is warranted.
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