Olfactory Dysfunction in Neurodegenerative Diseases

  • Concepció MarinEmail author
  • Dolores Vilas
  • Cristóbal Langdon
  • Isam Alobid
  • Mauricio López-Chacón
  • Antje Haehner
  • Thomas Hummel
  • Joaquim MullolEmail author
Rhinosinusitis (J Mullol, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Rhinosinusitis


Purpose of Review

The sense of smell is today one of the focuses of interest in aging and neurodegenerative disease research. In several neurodegenerative diseases, such as Parkinson’s disease and Alzheimer’s disease, the olfactory dysfunction is one of the initial symptoms appearing years before motor symptoms and cognitive decline, being considered a clinical marker of these diseases’ early stages and a marker of disease progression and cognitive decline. Overall and under the umbrella of precision medicine, attention to olfactory function may help to improve chances of success for neuroprotective and disease-modifying therapeutic strategies.

Recent Findings

The use of olfaction, as clinical marker for neurodegenerative diseases is helpful in the characterization of prodromal stages of these diseases, early diagnostic strategies, differential diagnosis, and potentially prediction of treatment success. Understanding the mechanisms underlying olfactory dysfunction is central to determine its association with neurodegenerative disorders. Several anatomical systems and environmental factors may underlie or contribute to olfactory loss associated with neurological diseases, although the direct biological link to each disorder remains unclear and, thus, requires further investigation.


In this review, we describe the neurobiology of olfaction, and the most common olfactory function measurements in neurodegenerative diseases. We also highlight the evidence for the presence of olfactory dysfunction in several neurodegenerative diseases, its value as a clinical marker for early stages of the diseases when combined with other clinical, biological, and neuroimage markers, and its role as a useful symptom for the differential diagnosis and follow-up of disease. The neuropathological correlations and the changes in neurotransmitter systems related with olfactory dysfunction in the neurodegenerative diseases are also described.


Olfaction neurodegeneration clinical marker Parkinson’s disease Alzheimer’s disease olfactory bulbs dopamine 


Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.


Papers of particular interest, published recently, have been highlighted as:•• Of major Importance

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Concepció Marin
    • 1
    Email author
  • Dolores Vilas
    • 2
  • Cristóbal Langdon
    • 1
    • 3
  • Isam Alobid
    • 1
    • 3
    • 4
  • Mauricio López-Chacón
    • 1
    • 3
  • Antje Haehner
    • 5
  • Thomas Hummel
    • 5
  • Joaquim Mullol
    • 1
    • 3
    • 4
    Email author
  1. 1.INGENIO, IRCE, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), CELLEX, Department 2BBarcelonaSpain
  2. 2.Neurodegenerative Diseases Unit, Neurology ServiceUniversity Hospital Germans Trias i PujolBadalonaSpain
  3. 3.Rhinology Unit and Smell Clinic, ENT DepartmentHospital ClínicBarcelonaSpain
  4. 4.Centre for Biomedical Investigation in Respiratory Diseases (CIBERES)BarcelonaSpain
  5. 5.Smell and Taste Clinic, Department of OtorhinolaryngologyTechnische Universität DresdenDresdenGermany

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