title: Olfactory dysfunction is associated with subjective memory complaints in community-dwelling elderly individuals.
abstract: Olfactory dysfunction has been reported in clinical and preclinical phases of Alzheimer's disease. Subjective memory complaints have been proposed as a potential early indicator for increased risk of Alzheimer's disease, but have also been associated with depression, personality characteristics, and health problems. In this study, we aimed to determine which of these putative markers can predict memory complaints in community-dwelling elderly individuals, focusing on olfactory symptoms. A cohort of 144 elderly volunteers (42 males and 102 females), aged 50 to 86, was recruited from an ongoing longitudinal study. Participants were assessed for olfactory capacities (threshold, discrimination, and identification), subjective memory complaints, depression, and cognitive functions. Subjective memory complaints were significantly associated with olfactory discrimination and identification but not with threshold. Olfactory functions and depressive symptoms were both significantly associated with subjective memory complaints. In addition, memory complainers were significantly worse than non-complainers with respect to olfactory discrimination, identification, and overall olfactory functioning. The findings suggest that olfactory capacity may be a potentially significant biomarker for identifying community-dwelling elderly with memory complaints who are at increased risk for age-related cognitive decline and Alzheimer's disease.
authors.affiliation: The School of Psychiatry and Clinical Neuroscience, University of Western Australia, Crawley, WA, Australia.
authors.forename: Hamid R
authors.initials: HR
authors.lastname: Sohrabi
authors.forename: Kristyn A
authors.initials: KA
authors.lastname: Bates
authors.forename: Mark
authors.initials: M
authors.lastname: Rodrigues
authors.forename: Kevin
authors.initials: K
authors.lastname: Taddei
authors.forename: Simon M
authors.initials: SM
authors.lastname: Laws
authors.forename: Nicola T
authors.initials: NT
authors.lastname: Lautenschlager
authors.forename: Satvinder S
authors.initials: SS
authors.lastname: Dhaliwal
authors.forename: Amy N B
authors.initials: AN
authors.lastname: Johnston
authors.forename: Alan
authors.initials: A
authors.lastname: Mackay-Sim
authors.forename: Samuel
authors.initials: S
authors.lastname: Gandy
authors.forename: Jonathan K
authors.initials: JK
authors.lastname: Foster
authors.forename: Ralph N
authors.initials: RN
authors.lastname: Martins
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000150:complications*; D008875:Middle Aged; D009483:Neuropsychological Tests; D000857:Olfaction Disorders / Q000209:etiology*; D011569:Psychiatric Status Rating Scales; D012044:Regression Analysis; D012111:Residence Characteristics; D012720:Severity of Illness Index; D012737:Sex Factors; D011795:Surveys and Questionnaires