People with poor hearing are more likely to suffer from dementia when they are older, scientists in the US have claimed.
Someone with mild hearing loss is twice as likely to develop dementia than someone with normal hearing. The scientists said they arrived at the conclusion after accounting for age and other influential factors.
Those with moderate hearing loss are said to be three times as likely to get dementia and severe hearing loss increases the risk five-fold.
Whether damaged hearing and declining mental function is linked is another matter, the researchers pointed out. They said more tests would be needed to determine whether it is the deafness itself which causes dementia or if it is the isolation resulting from the deafness that leads to a person losing their mental abilities.
None of the 639 participants, aged 36–90, had dementia at the beginning of the study when they all had their hearing tested. However, 9% developed dementia (mostly Alzheimer's) during the 12-year research period. The results showed that dementia risk was higher in those who had the worst hearing.
The Archives of Neurology published the findings of the study which was conducted at Johns Hopkins University in Baltimore.