Longitudinal changes in hearing and visual impairments associated with risk of dementia in older adults: The Cardiovascular Health Study

Abstract

AbstractBackgroundTo determine whether dual sensory impairment (DSI) is associated with incident dementia in older adults. We hypothesized that DSI is associated with increased risk of dementia as compared to no sensory impairment. We also assessed whether duration of DSI is associated with risk of dementia.MethodProspective cohort study from the Cardiovascular Health Study. Hearing and vision impairments collected via self‐report at baseline and up to five follow‐up visits from 1992 to 1999. All‐cause dementia, Alzheimer's disease (AD), and vascular dementia (VaD) classified by a multi‐disciplinary committee using standardized criteria. Time‐dependent Cox regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) in order to estimate the risk of dementia associated with time‐varying number of sensory impairments (0, 1, or 2)ResultA total of 2,927 participants with information on hearing and vision at all available study visits were included in the analysis. At baseline, participants had a mean age of 74.6 years and consisted of 1,704 (58.2%) women. Compared to no sensory impairment, DSI was associated with increased risk of all‐cause dementia (HR = 2.60; 95% CI = 1.66 to 2.06; P <.001), AD (HR = 3.67; 95% CI = 2.04 to 6.60; P <.001), and VaD (HR = 2.03; 95% CI = 1.00 to 4.09; P = .05). Each additional year with DSI was associated with a 31% increased risk for all‐cause dementia (HR = 1.31; 95% CI = 1.07 to 1.62; P = .02) and 46% increased risk for AD (HR = 1.46; 95% CI = 1.12 to 1.91; P = .01).ConclusionIn this cohort study, DSI was strongly associated with increased risk of dementia, particularly AD. Evaluation of hearing and vision in older adults may help to identify those at high risk of developing dementia.