Hearing impairment and cognitive decline: a pilot study conducted within the atherosclerosis risk in communities neurocognitive study

Abstract

Hearing impairment (HI) is prevalent, is modifiable, and has been associated with cognitive decline. We tested the hypothesis that audiometric HI measured in 2013 is associated with poorer cognitive function in 253 men and women from Washington County, Maryland (mean age = 76.9 years) in a pilot study carried out within the Atherosclerosis Risk in Communities Neurocognitive Study. Three cognitive tests were administered in 1990-1992, 1996-1998, and 2013, and a full neuropsychological battery was administered in 2013. Multivariable-adjusted differences in standardized cognitive scores (cross-sectional analysis) and trajectories of 20-year change (longitudinal analysis) were modeled using linear regression and generalized estimating equations, respectively. Hearing thresholds for pure tone frequencies of 0.5-4 kHz were averaged to obtain a pure tone average in the better-hearing ear. Hearing was categorized as follows: ≤25 dB, no HI; 26-40 dB, mild HI; and >40 dB, moderate/severe HI. Comparing participants with moderate/severe HI to participants with no HI, 20-year rates of decline in memory and global function differed by -0.47 standard deviations (P = 0.02) and -0.29 standard deviations (P = 0.02), respectively. Estimated declines were greatest in participants who did not wear a hearing aid. These findings add to the limited literature on cognitive impairments associated with HI, and they support future research on whether HI treatment may reduce risk of cognitive decline.

Keywords: aging; cognition; cognitive decline; hearing impairment; memory; perbycussis.

Figure 1.

Mean standardized cognitive test scores observed over time, by hearing impairment status, among participants in the Atherosclerosis Risk in Communities Neurocognitive Study (n = 253), 1990–2013. A) Delayed Word Recall Test; B) Word Fluency Test; C) Digit Symbol Substitution Test; D) global longitudinal composite score. Hearing impairment was measured in 2013.

Figure 2.

Multivariable-adjusted estimates of mean standardized cognitive test scores over time, by hearing impairment status, Atherosclerosis Risk in Communities Neurocognitive Study (n = 253), 1990–2013. A) Delayed Word Recall Test; B) Word Fluency Test; C) Digit Symbol Substitution Test; D) global longitudinal composite score. Estimates were adjusted for age (years), age² (years²), sex, education (high school or less vs. more than high school), smoking status (ever smoking vs. never smoking), diabetes (fasting blood glucose concentration ≥126 mg/dL or participant self-report and medication use for diabetes), hypertension (diastolic blood pressure ≥90 mm Hg, systolic blood pressure ≥140 mm Hg, or use of hypertensive medication), and Wide Range Achievement Test score. Hearing impairment was measured in 2013.