Neurodegenerative disorders, such as Alzheimer dementia and Parkinson disease, are disabling diseases that present a burden on society that rivals the costs of cancer and heart disease. Although current therapies are often unsuccessful at reversing the progression of these diseases, early detection in patients who are at risk of neurodegenerative disease could allow for timely interventions to delay and minimize the loss of brain function over time.
Olfactory impairment has been shown to be a preclinical marker for Alzheimer dementia, which may predate the onset of dementia by many years.1 However, the screening for olfactory impairment is extremely limited in current clinical practice, and the need exists for better biomarkers that can identify at-risk patients and demonstrate real-time response to therapies. Clinical biomarkers from studies that were performed in the workup of patients with neurodegenerative diseases, such as magnetic resonance imaging (MRI) scans, are ideal for identifying sensitive and specific changes that occur in advance of symptomatic disease.