The study led by Professor Chen Shanquan finds that effective use of hearing aids may help reduce dementia risk in older adults.
The School of Public Health at the LKS Faculty of Medicine, the University of Hong Kong (HKUMed), together with a multinational team, has found that the effective use of hearing aids is associated with a lower risk of probable dementia among older adults with hearing loss. The findings highlight the importance of quality hearing rehabilitation for healthy ageing and were published in Cell Reports Medicine [link to the publication].
Dementia is projected to affect 150 million people worldwide by 2050, placing a significant burden on healthcare systems and societies. Hearing loss, a common condition affecting approximately 30% of people over 65 and up to 90% of those aged 85 and older, has emerged as one of the most important potentially modifiable risk factors for dementia.
According to the 2024 Lancet Commission, hearing loss accounts for approximately 7% of dementia cases, making it a leading modifiable risk factor. Professor Chen Shanquan, Assistant Professor in the School of Public Health, HKUMed, and joint last author of the study, said, 'While hearing aids are widely regarded as the standard first-line treatment for adult hearing loss, their role in preventing cognitive decline has remained uncertain.'
Effective hearing aids linked to 14% lower dementia risk
The study analysed data from 61,089 hearing-impaired adults aged 55 and older, drawn from seven ageing cohorts across 33 countries, including China, Korea, Europe, the UK, the US, Ireland and Mexico. Over an average follow-up period of 6.5 years, 8,911 participants developed probable dementia.
The study found that hearing aid users had a 9% lower risk of probable dementia compared to hearing-impaired non-users. Importantly, the benefit appeared to depend on the effectiveness of the devices. Participants who reported good hearing improvement with hearing aids had a 14% lower risk of probable dementia, whereas those who reported poor hearing improvement showed no significant reduction in risk.
The association 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 a hearing aid, compared with 20% in high-income countries. Together, these findings suggest that improving both access to hearing aids and the quality of hearing rehabilitation should be key public health priorities.
Prioritising hearing care for at-risk groups
The study also found that the association between hearing aid use and lower dementia risk was more pronounced among women, unmarried individuals and those with lower educational attainment. This suggests that hearing rehabilitation may be particularly important for socially vulnerable groups, who may face a higher risk of isolation or reduced access to health resources.
Building on these findings, the researchers have called for future research using objective hearing assessments, real-world device-use data, and more representative samples from low-resource settings. They also recommend that hearing care should be better integrated into dementia prevention, primary care, and healthy-ageing strategies.
The researchers emphasised that the study was observational and cannot prove that hearing aids directly prevent dementia. Nevertheless, the results provide large-scale, multi-country evidence that effective hearing rehabilitation may be linked to better cognitive ageing outcomes.
Bridging gaps in hearing care across regions
Professor Chen Shanquan said, 'Hearing loss is increasingly recognised as one of the most important risk factors for dementia that can potentially be addressed. Our study suggests that the benefit is not simply about wearing a device, but whether the device meaningfully improves hearing in daily life.'
'These findings have important implications for healthy ageing policies,' Professor Chen added. In high-income settings, the priority may be on fitting improvement, follow-up care and the long-term effectiveness of hearing aids. In middle-income settings, however, expanding affordable access to hearing care remains a major challenge.'
About the research team
The study was jointly led by Professor Chen Shanquan of the School of Public Health, HKUMed, and Professor Xu Lei of Shandong Provincial ENT Hospital, Shandong University. The co-first authors were Dr Jiang Fan and Dr Dong Qiuyue from the School of Public Health, HKUMed. The research team comprises members from multiple international institutions, including the University of Western Australia, Yale University, King's College London, New York University, the University of Cambridge, Sun Yat-sen University, Peking University, City University of Hong Kong, and the Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences.
