title: Olfaction and risk of dementia in a biracial cohort of older adults.
abstract: OBJECTIVE
  Prior studies indicate that olfactory function may be an early marker for cognitive impairment, but the body of evidence has been largely restricted to white populations.
  
  
  METHODS
  We studied 2,428 community-dwelling black and white older adults (baseline age 70-79 years) without dementia enrolled in the Health, Aging, and Body Composition (Health ABC) study. Olfaction was measured as odor identification (OI) with the 12-item Cross Cultural Smell Identification Test in year 3. We defined incident dementia over 12 years on the basis of hospitalization records, prescription for dementia medication, or 1.5-SD decline in race-stratified global cognition score. We assessed dementia risk associated with OI score (by tertile) using Cox proportional hazards models. All analyses were stratified by race.
  
  
  RESULTS
  Poorer OI in older adults without dementia was associated with increased risk of dementia. After adjustment for demographics, medical comorbidities, and lifestyle characteristics, white participants in the poor or moderate OI tertile had greater risk of dementia (adjusted hazard ratio [HR] 3.34, 95% confidence interval [CI] 2.45-4.54; and HR 1.84, 95% CI 1.33-2.54, respectively) compared to those in the good tertile of function. Among blacks, worse OI was associated with an increased risk of dementia, but the magnitude of the effect was weaker (p for interaction = 0.04) for the poor OI tertile (adjusted HR 2.03, 95% CI 1.44-2.84) and for the moderate tertile (adjusted HR 1.42, 95% CI 0.97-2.10). There was no interaction between OI and APOE ε4 and risk of dementia.
  
  
  CONCLUSIONS
  While the magnitude of the association was stronger in whites, we found that poor OI was associated with increased risk of dementia among both black and white older adults.
authors.affiliation: From the Departments of Psychiatry (K.Y.), Neurology (K.Y.), and Epidemiology and Biostatistics (K.Y., S.R.), University of California; San Francisco VA Medical Center (K.Y.); NCIRE-The Veterans Health Research Institute (K.Y., D.F.), San Francisco, CA; Epidemiology Branch (H.C.), National Institute of Environmental Health Sciences, Research Triangle Park, NC; Department of Preventive Medicine (K.A.), University of Tennessee Health Science Center, Memphis; Department of Epidemiology (A.R.), Graduate School of Public Health, University of Pittsburgh, PA; California Pacific Medical Center Research Institute (G.T., S.C.), San Francisco; and Translational Gerontology Branch (E.S.), National Institute on Aging, Baltimore, MD.
authors.forename: Kristine
authors.initials: K
authors.lastname: Yaffe
authors.affiliation: From the Departments of Psychiatry (K.Y.), Neurology (K.Y.), and Epidemiology and Biostatistics (K.Y., S.R.), University of California; San Francisco VA Medical Center (K.Y.); NCIRE-The Veterans Health Research Institute (K.Y., D.F.), San Francisco, CA; Epidemiology Branch (H.C.), National Institute of Environmental Health Sciences, Research Triangle Park, NC; Department of Preventive Medicine (K.A.), University of Tennessee Health Science Center, Memphis; Department of Epidemiology (A.R.), Graduate School of Public Health, University of Pittsburgh, PA; California Pacific Medical Center Research Institute (G.T., S.C.), San Francisco; and Translational Gerontology Branch (E.S.), National Institute on Aging, Baltimore, MD. kristine.yaffe@ucsf.edu.
authors.forename: Daniel
authors.initials: D
authors.lastname: Freimer
authors.affiliation: From the Departments of Psychiatry (K.Y.), Neurology (K.Y.), and Epidemiology and Biostatistics (K.Y., S.R.), University of California; San Francisco VA Medical Center (K.Y.); NCIRE-The Veterans Health Research Institute (K.Y., D.F.), San Francisco, CA; Epidemiology Branch (H.C.), National Institute of Environmental Health Sciences, Research Triangle Park, NC; Department of Preventive Medicine (K.A.), University of Tennessee Health Science Center, Memphis; Department of Epidemiology (A.R.), Graduate School of Public Health, University of Pittsburgh, PA; California Pacific Medical Center Research Institute (G.T., S.C.), San Francisco; and Translational Gerontology Branch (E.S.), National Institute on Aging, Baltimore, MD.
authors.forename: Honglei
authors.initials: H
authors.lastname: Chen
authors.affiliation: From the Departments of Psychiatry (K.Y.), Neurology (K.Y.), and Epidemiology and Biostatistics (K.Y., S.R.), University of California; San Francisco VA Medical Center (K.Y.); NCIRE-The Veterans Health Research Institute (K.Y., D.F.), San Francisco, CA; Epidemiology Branch (H.C.), National Institute of Environmental Health Sciences, Research Triangle Park, NC; Department of Preventive Medicine (K.A.), University of Tennessee Health Science Center, Memphis; Department of Epidemiology (A.R.), Graduate School of Public Health, University of Pittsburgh, PA; California Pacific Medical Center Research Institute (G.T., S.C.), San Francisco; and Translational Gerontology Branch (E.S.), National Institute on Aging, Baltimore, MD.
authors.forename: Keiko
authors.initials: K
authors.lastname: Asao
authors.affiliation: From the Departments of Psychiatry (K.Y.), Neurology (K.Y.), and Epidemiology and Biostatistics (K.Y., S.R.), University of California; San Francisco VA Medical Center (K.Y.); NCIRE-The Veterans Health Research Institute (K.Y., D.F.), San Francisco, CA; Epidemiology Branch (H.C.), National Institute of Environmental Health Sciences, Research Triangle Park, NC; Department of Preventive Medicine (K.A.), University of Tennessee Health Science Center, Memphis; Department of Epidemiology (A.R.), Graduate School of Public Health, University of Pittsburgh, PA; California Pacific Medical Center Research Institute (G.T., S.C.), San Francisco; and Translational Gerontology Branch (E.S.), National Institute on Aging, Baltimore, MD.
authors.forename: Andrea
authors.initials: A
authors.lastname: Rosso
authors.affiliation: From the Departments of Psychiatry (K.Y.), Neurology (K.Y.), and Epidemiology and Biostatistics (K.Y., S.R.), University of California; San Francisco VA Medical Center (K.Y.); NCIRE-The Veterans Health Research Institute (K.Y., D.F.), San Francisco, CA; Epidemiology Branch (H.C.), National Institute of Environmental Health Sciences, Research Triangle Park, NC; Department of Preventive Medicine (K.A.), University of Tennessee Health Science Center, Memphis; Department of Epidemiology (A.R.), Graduate School of Public Health, University of Pittsburgh, PA; California Pacific Medical Center Research Institute (G.T., S.C.), San Francisco; and Translational Gerontology Branch (E.S.), National Institute on Aging, Baltimore, MD.
authors.forename: Susan
authors.initials: S
authors.lastname: Rubin
authors.affiliation: From the Departments of Psychiatry (K.Y.), Neurology (K.Y.), and Epidemiology and Biostatistics (K.Y., S.R.), University of California; San Francisco VA Medical Center (K.Y.); NCIRE-The Veterans Health Research Institute (K.Y., D.F.), San Francisco, CA; Epidemiology Branch (H.C.), National Institute of Environmental Health Sciences, Research Triangle Park, NC; Department of Preventive Medicine (K.A.), University of Tennessee Health Science Center, Memphis; Department of Epidemiology (A.R.), Graduate School of Public Health, University of Pittsburgh, PA; California Pacific Medical Center Research Institute (G.T., S.C.), San Francisco; and Translational Gerontology Branch (E.S.), National Institute on Aging, Baltimore, MD.
authors.forename: Greg
authors.initials: G
authors.lastname: Tranah
authors.affiliation: From the Departments of Psychiatry (K.Y.), Neurology (K.Y.), and Epidemiology and Biostatistics (K.Y., S.R.), University of California; San Francisco VA Medical Center (K.Y.); NCIRE-The Veterans Health Research Institute (K.Y., D.F.), San Francisco, CA; Epidemiology Branch (H.C.), National Institute of Environmental Health Sciences, Research Triangle Park, NC; Department of Preventive Medicine (K.A.), University of Tennessee Health Science Center, Memphis; Department of Epidemiology (A.R.), Graduate School of Public Health, University of Pittsburgh, PA; California Pacific Medical Center Research Institute (G.T., S.C.), San Francisco; and Translational Gerontology Branch (E.S.), National Institute on Aging, Baltimore, MD.
authors.forename: Steve
authors.initials: S
authors.lastname: Cummings
authors.affiliation: From the Departments of Psychiatry (K.Y.), Neurology (K.Y.), and Epidemiology and Biostatistics (K.Y., S.R.), University of California; San Francisco VA Medical Center (K.Y.); NCIRE-The Veterans Health Research Institute (K.Y., D.F.), San Francisco, CA; Epidemiology Branch (H.C.), National Institute of Environmental Health Sciences, Research Triangle Park, NC; Department of Preventive Medicine (K.A.), University of Tennessee Health Science Center, Memphis; Department of Epidemiology (A.R.), Graduate School of Public Health, University of Pittsburgh, PA; California Pacific Medical Center Research Institute (G.T., S.C.), San Francisco; and Translational Gerontology Branch (E.S.), National Institute on Aging, Baltimore, MD.
authors.forename: Eleanor
authors.initials: E
authors.lastname: Simonsick
mesh_terms: D001741:Black or African American; D000368:Aged; D015897:Comorbidity; D003704:Dementia / Q000150:complications / Q000208:ethnology* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D000857:Olfaction Disorders / Q000150:complications / Q000208:ethnology / Q000523:psychology; D010414:Pennsylvania; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012306:Risk; D012727:Sex Characteristics; D012903:Smell; D013714:Tennessee; D044465:White People