Evaluation of the Association Between Hearing Aids and Reduced Cognitive Decline in Older Adults with Hearing Impairment

We investigated whether hearing aids (HAs) for hearing impairment may reduce cognitive decline in older adults. STUDY DESIGN: Retrospective cohort. SETTING: Ambulatory for medical checkup. PATIENTS: Comprised 1,453 older adults aged 65 to 90 years. INTERVENTION: HAs were recommended for hearing impairment with thresholds of ≥40 dB. MAIN OUTCOME MEASURES: The Mini-Mental State Examination (MMSE) and pure-tone audiometry were performed. Over 2 years, multivariate logistic regression analysis was used to assess the effects of sex, age, hearing, HAs, hypertension, diabetes, cerebrovascular disease, smoking, and drinking on MMSE scores. RESULTS: Of 1,453 participants who underwent MMSE, 1,320 who underwent audiometry in the first-year included 99 HA users. Of the 1,320 participants, 858 (89 HA users) were followed longitudinally for 1 year and 672 (66 HA users) for 2 years. In the first-year cross-sectional study, the risk ratios (RRs) for hearing impairment (≥25 dB) when the MMSE scores were ≤23 and ≤27 points were 2.97 (1.40–6.28) and 1.34 (1.01–1.79), respectively. For moderate (40–<70 dB) and moderate to severe (≥40 dB) hearing impairment, the RRs for HA use were 0.30 (0.11–0.86) and 0.50 (0.22–1.13), respectively, when the MMSE scores were ≤23. A 2-year follow-up of participants with moderate hearing impairment yielded hazard ratios for MMSE score decrease of 0.30 (0.11–0.82) after 1 year and 0.16 (0.04–0.64) after 2 years in HA users. CONCLUSIONS: HA use may be associated with reducing MMSE score decrease in older adults with moderate hearing impairment.