The Role of Olfactory Challenge Tests in Incipient Dementia and Clinical Trial Design

  • Peter W. SchofieldEmail author
  • Sally Finnie
  • Yun Ming Yong
Dementia (KS Marder, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Dementia


The brain changes associated with Alzheimer’s disease (AD) develop slowly over many years before the onset of dementia. Biomarkers for AD that allow its detection during this clinically silent phase will be hugely important when disease-modifying treatments that halt or slow its progression become available. Early detection, leading to early treatment, may in some cases avert dementia. Biomarkers aid our understanding of the presymptomatic stages of the disease and enable the identification of individuals with early disease who, by participating in clinical trials of investigational treatments with disease-modifying potential, contribute unique and vital information necessary to evaluate novel therapies. Most currently available AD biomarkers are expensive and not widely available and there are major efforts underway to find cheaper, simpler options. The olfactory system is affected by AD and the results from simple and inexpensive tests of the sense of smell, especially when paired with other information, can help identify individuals early in the disease. We review recent literature relevant to the use of simple olfactory tests, including some novel approaches, as aids to the early detection of AD. We consider their possible role in the design and conduct of clinical trials and suggest how in the future, when more effective treatments become available, they might be integrated into screening programs for early AD detection.


Olfaction Screening Biomarkers Alzheimer’s disease Dementia Clinical trials 


Compliance with Ethics Guidelines

Conflict of Interest

In the studies referred to in this work undertaken by the authors, informed consent was obtained from all participants.

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 importance

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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Peter W. Schofield
    • 1
    Email author
  • Sally Finnie
    • 2
  • Yun Ming Yong
    • 3
  1. 1.Centre for Translational Neuroscience and Mental HealthUniversity of NewcastleNewcastleAustralia
  2. 2.Department of PsychologyMacquarie UniversitySydneyAustralia
  3. 3.University of NewcastleNewcastleAustralia

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