Association of Olfactory Dysfunction With Risk for Future Parkinson's Disease

Ann Neurol. 2008 Feb;63(2):167-73. doi: 10.1002/ana.21291.

Abstract

Objective: Although olfactory dysfunction is commonly associated with Parkinson's disease (PD), it is not known whether such dysfunction can predate the onset of clinical PD in a community-based population. This study examines the association of olfactory dysfunction with future development of PD in Honolulu-Asia Aging Study cohort members

Methods: Olfaction was assessed from 1991 to 1996 in 2,267 men in the Honolulu-Asia Aging Study aged 71 to 95 years who were free of clinical PD and dementia at the time of olfaction testing. Participants were followed for up to 8 years for incident PD RESULTS: In the course of follow-up, 35 men were diagnosed with PD (24.6/10,000 person-years). The average age at the time of diagnosis was 82.9 +/- 3.8 (range, 76-93) years, and the average time to a diagnosis was 4.0 +/- 1.9 (range, 1-8) years. During the first 4 years of follow-up, age-adjusted incidence of PD declined from 54.5/10,000 person-years in the lowest quartile of odor identification to 26.6, 8.2, and 8.4/10,000 person-years in the second, third, and fourth quartiles, respectively (p < 0.001 for trend). After adjustment for age and other potential confounders, the odds ratios for PD in the lowest quartile was 5.2 (95% confidence interval, 1.5-25.6) compared with the top two quartiles. This relation was not evident beyond 4 years of follow-up.

Interpretation: Impaired olfaction can predate clinical PD in men by at least 4 years and may be a useful screening tool to detect those at high risk for development of PD in later life.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Asian Americans / statistics & numerical data
  • Brain / physiopathology
  • Cell Differentiation / physiology
  • Cohort Studies
  • Comorbidity
  • Disease Progression
  • Early Diagnosis
  • Hawaii / epidemiology
  • Humans
  • Incidence
  • Longitudinal Studies
  • Male
  • Mass Screening
  • Olfaction Disorders / diagnosis*
  • Olfaction Disorders / epidemiology*
  • Olfaction Disorders / physiopathology
  • Olfactory Pathways / physiopathology
  • Parkinson Disease / diagnosis*
  • Parkinson Disease / epidemiology*
  • Parkinson Disease / physiopathology
  • Predictive Value of Tests
  • Prevalence
  • Prognosis
  • Risk Factors
  • Smell / physiology