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The Relationship between Age-Related Macular Degeneration and Olfactory Function
Taner Kar1, Yildiray Yildirim, Aytuğ Altundağ
1Department of Ophthalmology, GATA Haydarpaşa Training Hospital, Istanbul, Turkey.
Neuro-Degenerative Diseases
|April 15, 2015
Summary
Patients with age-related macular degeneration (AMD) experience significant olfactory dysfunction, impacting odor discrimination and identification even in early stages. This decline worsens with disease progression and reduced visual acuity.
Area of Science:
- Ophthalmology
- Neuroscience
- Gerontology
Background:
- Olfactory dysfunction is a common symptom in neurodegenerative diseases.
- Age-related macular degeneration (AMD) is a late-onset neurodegenerative condition.
Purpose of the Study:
- To investigate olfactory function in patients diagnosed with AMD.
- To compare olfactory abilities between AMD patients and healthy controls.
Main Methods:
- 138 subjects (69 AMD patients, 69 controls) underwent ophthalmic evaluation.
- AMD patients were subclassified into early- and late-stage groups.
- Olfactory function was assessed using the Sniffin' Sticks test.
Main Results:
- AMD patients exhibited decreased olfactory abilities, particularly in odor discrimination and identification, even in early stages.
- Olfactory decline was more pronounced across all tasks in advanced AMD stages.
- Worsening visual acuity in AMD patients correlated with diminished olfactory function.
Conclusions:
- Age-related macular degeneration negatively impacts all aspects of orthonasal olfaction, especially in advanced stages.
- Similar to other neurodegenerative disorders, odor discrimination and identification are more severely affected than odor detection thresholds.
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