Association between Auditory Impairment and the Onset of Alzheimer’s Disease: The LIFE Study

Abstract

AbstractBackgroundThe prevalence of Alzheimer’s Disease (AD) has seen an upward trend due to the demographic shift towards an aging population in Japan. The possible association between auditory impairment and the onset of AD has been previously proposed, however, it remains a subject of ongoing discussion. This study aimed to investigate this association using data from 13 municipalities in Japan.MethodFrom the LIFE Study, 13 municipalities that possessed both long‐term care certification questionnaire and medical claims data were identified as eligible for inclusion. The study population consisted of individuals who had newly applied for long‐term care certification between April 2013 and October 2021. The study population consisted of individuals who displayed no cognitive impairment at the time of application and had not been diagnosed with dementia within the preceding six months, inclusive of the month of application. The month succeeding the application was established as the index month, and the interval from this month to the onset of AD (ICD‐10 codes F00 or G30) was assessed. The Cox proportional hazards model was utilized to examine the risk of AD onset in relation to auditory status as reported on the long‐term care certification questionnaire.ResultThe study cohort consisted of 33,067 participants, with a mean follow‐up duration of 21.0 months. At the index month, 60.2% of the patients were female, and the mean age was 79.5 years. In the course of the follow‐up period, 1,827 (5.53%) individuals developed AD. Auditory impairment was not found to be correlated with the incidence of AD. The hazard ratio (HR) for the development of AD in relation to auditory impairment was 1.31 (95% Confidence Interval: 0.65 ‐ 2.64).ConclusionThe examination of the long‐term care certification questionnaire data did not reveal any correlation between auditory function and the onset of AD. The limitations of this study include the inability to determine the use of hearing aids or the timing of onset of auditory impairment. Further investigations are necessary to clarify the relationship between auditory function and dementia.