Sensory Impairments and Risk of Mortality in Older Adults

Sensory impairments increase with age and the majority of older people will experience a sensory impairment if they live long enough. However, the relationships of hearing, visual, and olfactory impairments with mortality are not well understood.

Epidemiology of Hearing Loss Study participants (n = 2,418) aged 53-97 years (mean = 69 years) were examined in 1998-2000 and hearing, visual acuity, and olfaction were measured. Participants were followed for mortality for up to 17 years (mean = 12.8 years). Cox proportional hazards models were used to assess the association between prevalent sensory impairments and the 15-year cumulative incidence of death.

A total of 1,099 (45.4%) of participants died during the follow-up period. In age- and sex-adjusted Cox models, the risk of mortality was higher among participants with one (hazard ratio [HR] = 1.40, 95% confidence interval [CI] = 1.19, 1.64) or two or more (HR = 2.12, 95% CI = 1.74, 2.58) sensory impairments than among participants with no sensory impairments. Olfactory impairment at baseline was significantly associated with mortality (HR = 1.28, 95% CI = 1.07, 1.52) after adjusting for age, sex, sensory comorbidities, cardiovascular risk factors and disease, cognitive impairment, frailty, subclinical atherosclerosis, and inflammatory marker levels (n = 1,745). Hearing and visual impairment were not associated with mortality after adjusting for subclinical atherosclerosis and inflammation.

Olfactory impairment, but not hearing or visual impairment, was associated with an increased risk of mortality. These results suggest that olfactory impairment may be a marker of underlying physiologic processes or pathology that is associated with aging and reduced survival in older adults.