Relationships between hearing impairment with 7‐year cognition and cognitive change: Results from the Study of Latinos‐ Investigation of Neurocognitive Aging (SOL‐INCA)

Abstract

AbstractBackgroundHearing impairment among Hispanics/Latinos has been associated with poorer cognition, potentially increasing mild cognitive impairment (MCI) and dementia risk. We aimed to examine associations between baseline hearing impairment with 1) cognition at visit 2 (7‐years later, on average), 2) 7‐year average change in cognition, and 3) mild cognitive impairment (MCI) at visit 2 among diverse Hispanics/Latinos.MethodHispanics/Latinos (n = 6031, average baseline age 56.4‐years) from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) were enrolled in the SOL ‐ Investigation of Neurocognitive Aging (SOL‐INCA) ancillary study. Hearing impairment was defined as a pure tone average (500, 1,000, 2,000, 4,000 Hz) >25 dBHL in the better ear. Cognitive testing was performed at Visit 1 and again an average of 7‐years later. Tests included measures of learning and memory, verbal fluency, and executive functioning and processing speed, and global cognition (a z‐score composite from averaging each test). MCI was calculated based on NIA‐AA criteria. Survey linear regressions were used to separately model the associations between hearing impairment with outcomes of interest, controlling for age, gender, education, Hispanic/Latino background, field center, marital status, depressive symptoms, income, and Framingham cardiovascular disease risk.ResultPerformance at visit 2: In fully adjusted models, hearing impairment at baseline was associated with lower scores in global cognition (B = ‐0.12; SE = 0.03; p<0.0001) evident in learning, memory and verbal fluency, but not executive function or processing speed at visit 2 (7 years later). 7‐year (average) cognitive change: Hearing impairment was associated with significant change (declines) in processing speed (B = ‐0.12; SE = 0.06; p<0.05) but not with change in global cognition or other cognitive domains. MCI: Hearing impairment was not associated with prevalent MCI.ConclusionWe found that hearing impairment was related to lower cognitive function and increased cognitive decline compared to Hispanics/Latinos with normal hearing. Hearing impairment was not associated with MCI among Hispanics/Latinos, and further longitudinal data are needed to determine if this holds as the cohort continues to age. Future studies should also examine comorbid sensory impairments and type of hearing impairments (noise induced hearing loss, conductive, sensorineural) with cognitive trajectories and MCI risk.