Should olfactory dysfunction be used as a biomarker of Alzheimer’s disease?

A major effort in Alzheimer’s disease (AD) research is driven by the need to identify biomarkers of the disease. Such bio markers would ideally predict a prognosis of AD prior to the development of significant neuro pathology and subsequent loss of cognitive function. Early indicators of disease are especially important for implementing interventions while brain systems are still functioning relatively normally. Thus, determination of an accurate and robust biomarker model may be pivotal in reducing the global impact of AD. Currently, several biomarkers of AD are being explored. Concentrations of amyloid-b and tau in the cerebrospinal fluid, F-f luorodeoxyglucose, amyloid-b and hippocampal volume imaging, and neuropsychological testing are all being explored for their utility in predicting the onset and stage of AD [1]. A recent overview of the typical progression of these biomarkers has resulted in a timeline model of AD progression wherein abnormalities are first detected in amyloid-b biomarkers, followed by neurodegenerative and cognitive biomarkers [2].