title: Olfactory impairment in adults.
abstract: Olfactory function may be important for environmental and nutritional safety and enjoyment. Population-based epidemiological studies of olfaction are needed to understand the magnitude of the health burden, identify modifiable risk factors, and develop and test prevention and treatment strategies for olfactory impairment. However, measuring olfaction in large studies is challenging, requiring repeatable, efficient methods that can measure change over time. Two large cohort studies, the Epidemiology of Hearing Loss Study (EHLS) and the Beaver Dam Offspring Study (BOSS), included olfactory testing. In both studies, the San Diego Odor Identification Test (SDOIT) was used to measure olfaction. Subjects were asked to identify eight common household odors (such as coffee and chocolate). Olfactory impairment was defined as correctly identifying fewer than six out of eight odorants after two trials. The EHLS participants were age 53-95 years at the time of the first measurement (1998-2000), and participants in the BOSS were age 21-84 years. The prevalence of olfactory impairment in the EHLS was 25% overall, more common in men than women, and increased with age. Five years later olfaction was measured a second time and the majority (84%) of the EHLS participants were classified the same. Among those with impairment at the base line nearly one-third (31%) improved to unimpaired. This heterogeneity in olfactory impairment has unique implications for data analyses and predicting outcomes and associations. Preliminary data from the BOSS suggest the prevalence of olfactory impairment may be lower in younger generations. All these factors point to a continuing need for epidemiological studies of olfaction.
authors.affiliation: University of Wisconsin, Madison, Wisconsin, USA. Schubert@episense.wisc.edu
authors.forename: Carla R
authors.initials: CR
authors.lastname: Schubert
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Cruickshanks
authors.forename: Claire
authors.initials: C
authors.lastname: Murphy
authors.forename: Guan-Hua
authors.initials: GH
authors.lastname: Huang
authors.forename: Barbara E K
authors.initials: BE
authors.lastname: Klein
authors.forename: Ronald
authors.initials: R
authors.lastname: Klein
authors.forename: F Javier
authors.initials: FJ
authors.lastname: Nieto
authors.forename: James S
authors.initials: JS
authors.lastname: Pankow
authors.forename: Ted S
authors.initials: TS
authors.lastname: Tweed
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000857:Olfaction Disorders / Q000453:epidemiology*; D011159:Population Surveillance; D014922:Wisconsin / Q000453:epidemiology
references.citation: Science. 1984 Dec 21;226(4681):1441-3
references.pmid: 6505700
references.citation: J Gerontol. 1993 Jan;48(1):M26-32
references.pmid: 8418141
references.citation: Arch Otolaryngol Head Neck Surg. 1991 May;117(5):519-28
references.pmid: 2021470
references.citation: JAMA. 2002 Nov 13;288(18):2307-12
references.pmid: 12425708
references.citation: Am J Epidemiol. 1998 Nov 1;148(9):879-86
references.pmid: 9801018
references.citation: J Am Geriatr Soc. 2008 Aug;56(8):1517-21
references.pmid: 18662205
references.citation: Arch Otolaryngol Head Neck Surg. 2003 Oct;129(10):1041-6
references.pmid: 14568784
references.citation: Chem Senses. 2002 Sep;27(7):617-22
references.pmid: 12200341
references.citation: Arch Otolaryngol Head Neck Surg. 1997 Apr;123(4):367-72
references.pmid: 9109781
references.citation: Arch Otolaryngol Head Neck Surg. 2001 May;127(5):497-503
references.pmid: 11346423
references.citation: Acta Otolaryngol. 2007 Feb;127(2):167-74
references.pmid: 17364348
references.citation: Am J Rhinol. 2006 Jan-Feb;20(1):101-8
references.pmid: 16539304