From sweet to sweat: Hedonic olfactory range is impaired in Parkinson's disease

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • A. Mrochen - , University Hospital at the Friedrich-Alexander University Erlangen-Nürnberg (Author)
  • F. Marxreiter - , University Hospital at the Friedrich-Alexander University Erlangen-Nürnberg (Author)
  • Z. Kohl - , University Hospital at the Friedrich-Alexander University Erlangen-Nürnberg (Author)
  • J. Schlachetzki - , University Hospital at the Friedrich-Alexander University Erlangen-Nürnberg (Author)
  • B. Renner - , Institute of Clinical Pharmacology, University Hospital at the Friedrich-Alexander University Erlangen-Nürnberg (Author)
  • T. Schenk - , University Hospital at the Friedrich-Alexander University Erlangen-Nürnberg, Ludwig Maximilian University of Munich (Author)
  • J. Winkler - , University Hospital at the Friedrich-Alexander University Erlangen-Nürnberg (Author)
  • J. Klucken - , University Hospital at the Friedrich-Alexander University Erlangen-Nürnberg (Author)

Abstract

Introduction: Olfactory dysfunction and neuropsychological symptoms like depression and anhedonia are common non-motor symptoms in Parkinson's disease (PD). The assessment of both functional domains includes clinical examination, olfactory testing, and standardized questionnaires. While olfaction is readily assessed by functional tests, the distinction of anhedonia as a separate symptom from other depressive symptoms is challenging. Thus, a test focusing on the assessment of hedonic olfaction may be helpful in the assessment of neuropsychological symptoms in PD. Methods: We examined anhedonia by evaluating the perception of pleasantness of odors in PD patients (n = 57) and healthy controls (n = 46). Pleasantness of odors was registered on a visual 9-point scale. For the assessment of anhedonia we used the Snaith-Hamilton-Pleasure-Scale (SHAPS). Depression was evaluated with the Zung Self-Rating Depression Scale and the Beck Depression Inventory II. Results: PD patients showed a substantial reduction in hedonic olfaction compared to controls (hedonic score: 1.5 vs. 2.2). Hyposmia, one of the most prevalent non-motor symptoms in PD, was a confounding factor. However, even normosmic PD patients showed a reduced hedonic olfaction compared to controls (hedonic score: 1.6 vs. 2.2). Furthermore, we observed a correlation between hedonic olfaction and the SHAPS-score for PD patients even though positive SHAPS-rating was observed in 9% of PD patients only, while no correlation to depression was present. Conclusion: These findings suggest that reduced hedonic olfaction might be an additional neuropsychological feature, probably giving insights into changes in hedonic tone complementary to hyposmia and depression in PD.

Details

Original languageEnglish
Pages (from-to)9-14
Number of pages6
JournalParkinsonism and Related Disorders
Volume22
Publication statusPublished - 1 Jan 2016
Peer-reviewedYes

External IDs

PubMed 26627940
ORCID /0000-0003-0845-6793/work/139025218

Keywords

Keywords

  • Anhedonia, Depression, Hedonia, Non-motor symptoms, Olfaction, Parkinson's disease