• Olfaction;
  • smell disorders;
  • epidemiology;
  • aging;
  • Level of Evidence: 3c



The objective of this study was to determine the five-year incidence of olfactory impairment and associated risk factors in a general population of older adults.

Study Design:

Longitudinal population-based study.


Participants (n = 1,556) in the population-based Epidemiology of Hearing Loss Study had olfaction measured at the 5- and 10-year examinations (1998–2000 and 2003–2005, respectively). Olfactory ability was measured by the San Diego Odor Identification Test.


The five-year incidence of olfactory impairment was 12.5%. Incidence rates increased with age for men and women. In a multivariate model, age (odds ratio [OR] = 1.79, 95% CI, 1.61–2.00; for every five-year increase), a history of nasal polyps (OR = 2.33, 95% CI, 1.13–4.59), a history of deviated septum (OR = 2.05, 95% CI, 1.14–3.56), and a history of heavy alcohol use (OR = 1.84, 95% CI, 1.13–2.93) were associated with an increased risk of olfactory impairment, whereas use of lipid-lowering agents (OR = 0.68, 95% CI, 0.46–0.99; yes vs. no), exercising at least once a week (OR = 0.69, 95% CI, 0.48–0.98), and oral steroid use (OR = 0.37, 95% CI, 0.11–0.94) were associated with a decreased risk.


The five-year incidence of olfactory impairment is high in this population of older adults. Modifiable risk factors associated with impairment suggest some impairment could be amenable to prevention or treatment. Laryngoscope, 2011