Relationship between cognitive domains and hearing ability in memory clinic patients: How did the relationship change after 6 months of introducing a hearing aid?

Objective We aimed to evaluate the relationship between hearing ability and cognitive domains and determine how the relationship changes after 6 months of introducing a hearing aid. Methods We conducted a 6-month hearing aid lending study between September 2014 and March 2019, including 59 older participants who visited the Memory Clinic at the National Center for Geriatrics and Gerontology. The hearing level was assessed using pure tone audiometry. Speech intelligibility was measured using the monosyllabic word discrimination score. We assessed the relationship between hearing ability and cognitive domains using the Mini-Mental State Examination (MMSE) total score and four subscale scores (orientation, memory, attention, and language). Differences in the cognitive function between baseline (pre-) and 6 months later (post-) after introducing a hearing aid were also assessed. Results The pre-orientation score was significantly associated with the pure-tone average (p = 0.013), and the pre-language score was significantly associated with speech intelligibility (p = 0.006) after adjusting for confounders. None of the MMSE subscale scores were significantly different between pre- and post-scores, however, an expectation of improvement with continuous hearing aid use was implied in the attention domain. Conclusion We found a significant association between hearing ability and cognitive domains in individuals whose cognitive functions were not considered healthy. The presence of a potential relationship between cognitive domains, hearing ability, and auditory compensation is suggested.