People who have difficulty hearing speech against background noise face a higher risk of developing dementia, according to a study led by the University of Oxford.
The research, which involved analysing UK Biobank data relating to 82,000 people aged 60 years and older, found that those with poor hearing faced a 91% increased risk of developing dementia and those with “insufficient”, but better, hearing faced a 61% increased risk, when compared to people with normal hearing.
At the beginning of the 11-year study, participants were asked to identify spoken numbers against a background of white noise and were placed into three groups: normal hearing, insufficient hearing and poor hearing.
After 11 years, 1,285 participants were identified as developing dementia based on hospital inpatient and death register records.
The risk of dementia remained similar when restricting the analysis to dementia which developed after nine years, as well as within three years.
Dr Thomas Littlejohns, senior epidemiologist in the Nuffield Department of Population Health at the University of Oxford said: “Dementia affects millions of individuals worldwide, with the number of cases projected to treble in the next few decades. However, there is growing evidence that developing dementia is not inevitable and that the risk could be reduced by treating pre-existing conditions. Whilst preliminary, these results suggest speech-in-noise hearing impairment could represent a promising target for dementia prevention.”
Dr Katy Stubbs from charity Alzheimer’s Research UK added: “While most people think of memory problems when we hear the word dementia, this is far from the whole story.
“Many people with dementia will experience difficultly following speech in a noisy environment – a symptom sometimes called the ‘cocktail party problem’. This study suggests that these hearing changes may not just be a symptom of dementia, but a risk factor that could potentially be treated.”
The study is published in Alzheimer’s & Dementia, the journal of the Alzheimer’s Association.