Researchers from the School of Public Health at the Li Ka Shing Faculty of Medicine of the University of Hong Kong (HKUMed), in collaboration with an international research team, have found that effective hearing aid use may be associated with a lower risk of probable dementia among older adults with hearing loss. Published in Cell Reports Medicine, the study highlights the importance of high-quality hearing rehabilitation as part of healthy ageing strategies worldwide.
Dementia is expected to affect nearly 150 million people globally by 2050, creating growing challenges for healthcare systems and communities. Hearing loss, which affects around 30% of adults over 65 and as many as 90% of those aged 85 and older, has increasingly been recognised as one of the leading potentially modifiable risk factors for dementia. According to the 2024 Lancet Commission, hearing loss may account for approximately 7% of dementia cases worldwide.
The study analysed data from 61,089 adults aged 55 and above with hearing impairment across seven ageing cohorts spanning 33 countries, including China, Korea, Europe, the United Kingdom, the United States, Ireland and Mexico. Over an average follow-up period of 6.5 years, 8,911 participants developed probable dementia. Researchers found that hearing aid users had a 9% lower risk of probable dementia compared with hearing-impaired non-users.
Importantly, the protective association appeared to depend on how effectively the hearing aids improved daily hearing. Participants who reported good hearing improvement with their devices had a 14% lower risk of probable dementia, while those who reported poor improvement showed no significant reduction in risk. The findings suggest that simply wearing a hearing aid may not be enough, and that the quality and effectiveness of hearing rehabilitation play a critical role.
The association between hearing aid use and lower dementia risk appeared stronger in middle-income countries, where hearing aid adoption was substantially lower. Only 2.6% of hearing-impaired participants in these countries reported using hearing aids, compared with 20% in high-income countries. The benefits were also more pronounced among women, unmarried individuals and people with lower educational attainment, suggesting that hearing rehabilitation may be particularly valuable for socially vulnerable groups who may face greater risks of isolation and reduced access to healthcare resources.
Professor Chen Shanquan, Assistant Professor in the School of Public Health at HKUMed and joint last author of the study, said that hearing loss is increasingly recognised as one of the most important potentially addressable risk factors for dementia. He noted that the findings underscore the need not only to improve access to hearing aids but also to ensure that devices provide meaningful hearing improvement in everyday life. While the observational study cannot prove that hearing aids directly prevent dementia, the researchers believe the results provide strong international evidence supporting the integration of hearing care into dementia prevention, primary care and healthy-ageing policies.
More information: Fan Jiang et al, Hearing aid effectiveness and probable dementia risk across 33 countries: A pooled analysis of seven cohorts, Cell Reports Medicine. DOI: 10.1016/j.xcrm.2026.102802
Journal information: Cell Reports Medicine Provided by The University of Hong Kong
