Hearing loss warning sign of dementia

London: Those who are hard of hearing have greater chances of developing dementia as they age.

Scientists found those with mild hearing loss had nearly twice the chance of developing dementia compared to people with normal hearing.

The risk increased three-fold for those with moderate hearing loss, and five-fold for severe impairment, the journal Archives of Neurology reports.

However, scientists are not sure whether hearing loss and a decline in mental function go hand in hand, or whether deafness isolates a person, which in turn increases their risk of dementia, according to the Daily Mail.

The study led by Johns Hopkins University surgeon Frank Lin followed more than 600 men and women aged between 36 and 90 over an average of 12 years.

All had a hearing test done at the start of the study, but none had dementia at that point.

Overall, nine percent of the participants developed some kind of dementia during the study.

Colleagues showed that the worse the participants` hearing, the greater their dementia risk.

"Treating hearing loss is not going to hurt you, except perhaps your wallet," Lin said, noting that he is currently running a trial to see if treating hearing loss would delay the onset of dementia.