EAn international team of researchers reports in a study presented in the journal The Lancet Public Health that people with hearing loss without a hearing aid have a 42 percent increased risk of developing dementia. On the other hand, if the hearing impaired wore a hearing aid, the risk was similar to that of people with normal hearing, as reported by the team led by Dongshan Zhu from Shandong University in Jinan, China.
It analyzed data on 437,704 Britons aged 40 to 69 from a UK database. They had provided information about their hearing ability themselves and initially none of them suffered from dementia. The mean time until the check-up was around twelve years on average.
Common problems
It has long been known that age-related hearing loss significantly increases the risk of dementia. “When the sensory organs weaken, the risk of dementia also increases,” agrees Peter Berlit, neurologist and Secretary General of the German Society of Neurology (DGN). According to the DGN, around 50 million people worldwide have dementia, in Germany there are 1.6 million.
It has not yet been clearly proven whether hearing aids can make a significant contribution to the prevention of dementia. According to Berlit, this study shows this. It is therefore particularly advisable to use hearing aids as early as possible. It is interesting that glasses are generally accepted and used regularly in old age, said Berlit. “So far, this has not been the case enough with hearing aids.” Hearing impairments are noticed more often by people in the immediate vicinity than by those affected themselves. Older people, on the other hand, quickly notice poorer reading.
Other experts are more skeptical, including study co-author Fan Jiang, also from Shandong University. “The underlying connections between the use of hearing aids and a lower risk of dementia are unclear,” he said, according to a statement in the specialist journal. Further research is required.
Tim Griffiths, Professor of Cognitive Neurology at Newcastle University in the UK, is also cautious about the results. “This observational study must be interpreted with caution,” he told the UK’s Science Media Centre. Since no hearing tests were carried out for the database on which the study was based, the UK Biobank, the participants had to assess their hearing abilities themselves; such self-declarations are not reliable. In addition, the study can only show a connection, but not whether the use of hearing aids actually prevents dementia or whether other effects are decisive.
According to Griffiths, this requires studies in which some of the test subjects are fitted with hearing aids at an early stage and comparisons are possible with a second group who do not use them at the beginning. A corresponding investigation is currently taking place in the USA.