[A version of this abstract appears in: Dementia: the Latest Evidence Newsletter (RWHT) Volume 1 Issue 8 March 2011].
639 adults, aged 39-90 years old, were followed over an average of 12 years to see if those with hearing loss were more likely to develop dementia. About 9% of the participants developed dementia during this time, and those with hearing loss at the start of the study were at greater risk of developing dementia. This suggests there is a link between hearing loss and the risk of developing dementia. For every 10 decibels of hearing loss, there appears to be a 27% increase in the risk of developing dementia.
It is unclear why this association might exist. It is unknown whether hearing loss contributes to the risk of dementia, is a sign of early dementia, or whether dementia and age-related hearing loss involve similar processes. Expert reviewers of this study point out that if either of the last two scenarios are correct, then interventions to improve hearing would be unlikely to reduce the risk of dementia.
Behind the headlines: Hearing problems ‘may signal dementia’. London: NHS Choices, February 2nd 2011.
Lin, FR. Metter, EJ. O’Brien, RJ. [et al] (2011). Hearing Loss and Incident Dementia. Archives of Neurology, February 2011, Vol.68(2), pp.214-220.