The Epidemiology of Olfactory Disorders

Abstract

Insights into risk factors for olfactory decline are needed, because knowledge about its origin is limited. This impairment has important implications for human health. Several epidemiologic studies of olfaction provide insight into the prevalence of olfactory disorders. Here, we review the major population studies carried out on this topic to date. Our purpose is to characterize knowledge about olfactory disorders from human studies. We also describe the existing methods for measuring the sense of smell in population studies, present recent insights into the epidemiology of smell disorders, and discuss the risk factors identified to date. Synthesis of these data shows that olfactory dysfunction increases as people age and is worse in men. Further study of olfaction is warranted for gaining better information on the etiologies affecting its impairment, research that will have a large public health impact.

Neocortical Lewy bodies are associated with impaired odor identification in community-dwelling elders without clinical PD

“…Several risk factors have been associated with olfactory dysfunction [57]. In this study, there was lack of association between the last valid BSIT score and smoking or head injury.…”

Position paper on olfactory dysfunction

“…Estimates vary significantly according to sample demographics, definitions of impairment and assessment technique. The latter is particularly important, and the existing literature will therefore be classified according to assessment technique in the following sections [for a comprehensive review, please see ref (20) ].…”

Modeling the effectiveness of olfactory testing to limit SARS-CoV-2 transmission

“…In all analyses, we considered 80% of the population to participate in the screening protocol, examined performing olfactory testing either daily, every third day, or weekly, and infectiousness was taken to be proportional to the logarithm of viral load in excess of 10 6 virions/ml [22]. We modeled that 4% of individuals would have a COVID-19-independent olfactory dysfunction [29][30][31]. Details of both models and parameters are fully described in Materials and Methods.…”