Epidemiology of aging, dementia and age-related hearing loss

Objective: The aim of this work was to provide updated epidemiological data regarding the aging population, dementia and age related hearing loss. Study design: This was a review of available data. Results: Aging of the population has resulted in an important epidemiological transition, marked by a widespread increase in the prevalence of chronic diseases, including dementia, a disease with a devastating impact, for which currently there is no cure. In 2010 there were 35.6 million people with dementia worldwide and it is estimated that 48.1 million persons will be affected with dementia in 2020, and 90.3 million in 2040. It is therefore essential to identify known risk factors and to look for new ones, in order to be able to act quickly and effectively on those modifiable. Age related hearing loss or presbyacusis, an extremely common condition among aged individuals, is one of several factors that certainly plays an important role in increasing the risk of cognitive deficit and of developing dementia. The prevalence of hearing loss in American adults aged 70 years and above is 63%; in Europe nearly 30% of males and 20% of females have a hearing loss of 30 decibels or more at 70 years; and 55% of males, 45% of females at the age of 80 years; in Italy one individual in three over 60 years of age, and nearly 60% over 85 years, is affected by age related hearing loss. Conclusion: Several studies have underlined the association between dementia and age related hearing loss, although the underlying mechanisms are not yet clear; the risk of dementia increases three-fold for every 10 decibels of hearing loss.