Temporal Sequence of Hearing Impairment and Cognition in the Baltimore Longitudinal Study of Aging

BACKGROUND: Hearing impairment (HI) could be a risk factor for cognitive decline, but cognition could plausibly also affect psychoacoustic assessment of hearing with audiometry. We examined the temporal sequence of hearing and cognitive function among nondemented, community-dwelling older adults. METHODS: Hearing and cognition were assessed between 2012 and 2015 and 2 years thereafter in 313 nondemented participants aged ≥60 years in the Baltimore Longitudinal Study of Aging. Poorer hearing was defined by pure-tone average of 0.5-4 kHz tones in the better-hearing ear. Cognitive measures with either visual or auditory inputs were Trail-making Test Part B; Digit Symbol Substitution Test; California Verbal Learning Test immediate recall, short delay, and long delay; Digit Span Forward/Backward; Benton Visual Retention Test; and Mini-Mental State Examination. We used linear regression models for cross-sectional associations at each timepoint and autoregressive, cross-lagged models to evaluate whether baseline hearing impairment (Time 1) predicted cognitive performance 2 years after baseline (Time 2) and vice versa. RESULTS: Cross-sectionally, there were no associations between poorer hearing and cognitive performance. Longitudinally, poorer hearing was associated with declines in California Verbal Learning Test immediate (β = -0.073, SE = 0.032, p = .024), short-delayed (β = -0.134, SE = 0.043, p = .002), long-delayed (β = -0.080, SE = 0.032, p = .012) recall, and Digit Span Forward (β = -0.074, SE = 0.029, p = .011).) from Time 1 to Time 2. Cognitive performance at Time 1 did not predict change in hearing status at Time 2. CONCLUSIONS: Audiometric hearing impairment predicted short-term cognitive declines in both California Verbal Learning Test and auditory stimuli for attention.