Testing early signs of dementia in patients with smell disorders

Alpha-synuclein Rt-quic and Neurologic Symptoms in Persons With idiOpathic anosMiA

Observational Danish Dementia Research Centre · NCT05740683

This study is trying to see if people with smell problems show early signs of dementia with Lewy bodies, using a new test to help catch it sooner.

Quick facts

Study typeObservational
Enrollment100 (estimated)
Ages55 Years to 75 Years
SexAll
SponsorDanish Dementia Research Centre Research network
Locations2 sites (Copenhagen and 1 other locations)
Trial IDNCT05740683 on ClinicalTrials.gov

What this trial studies

This observational study aims to explore the relationship between idiopathic olfactory dysfunction and early warning signs of dementia with Lewy bodies (DLB). It utilizes a novel technique called Real-Time Quaking-Induced Conversion (RT-QuIC) to measure misfolded alpha-synuclein in patients with olfactory dysfunction compared to healthy controls. The study seeks to identify biomarkers and prodromal symptoms that could facilitate earlier diagnosis and intervention for DLB. By understanding these early signs, the research hopes to improve patient care and support the development of disease-modifying therapies.

Who should consider this trial

Good fit: Ideal candidates are individuals aged 55-75 with slowly progressing idiopathic olfactory dysfunction.

Not a fit: Patients with diagnosed neurodegenerative diseases or those whose olfactory dysfunction is due to other medical conditions will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to earlier diagnosis and treatment options for patients at risk of developing dementia.

How similar studies have performed: While the approach of using RT-QuIC is novel, similar studies have shown promise in identifying early biomarkers for neurodegenerative diseases.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion criteria with patients iOD:

* Age 55 -75 years of age
* Slowly progressing and non-fluctuating iOD
* Able to give informed consent and to cooperate as evaluated by the PI

Exclusion criteria with patients iOD:

* Diagnosed with a neurodegenerative disease or major neurological/psychiatric condition.
* Anosmia/hyposmia caused by sino-nasal disease (including chronic rhinitis and allergy), after trauma, infection, congenial, olfactory dysfunction due to surgery, or toxins/drugs affecting the olfactory function.
* Olfactory dysfunction with response to systemic or local corticosteroids if tried
* Severe nasal cavity abnormalities or infections.
* Overt signs of dementia or PD
* Current alcohol or drug abuse
* Terminal illness
* Diagnosed with neurodegenerative disease or major neurological/psychiatric condition.

Inclusion criteria controls:

* Age 55 -75 years of age
* Able to give informed consent
* Able to cooperate as evaluated by the PI

Exclusion criteria controls:

* Olfactory dysfunction on clinical test
* Overt signs of dementia or PD
* Severe nasal cavity abnormalities or infections.
* Current alcohol or drug abuse
* Diagnosed with neurodegenerative disease or major neurological/psychiatric condition.

Where this trial is running

Copenhagen and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Idiopathic AnosmiaIdiopathic HyposmiaIdiopathic Olfactory DysfunctionRT-QuICalpha-synucleinIdiopathic anosmiaIdiopathic hyposmiaIdiopathic olfactory dysfunction
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.