Hearing loss: a major public health issue?

Hearing loss is not a minor inconvenience in someone’s life. Many patients are desperate and socially isolated by their inability to hear what is going on around them.

They are people of all ages united by a common problem – permanent damage to the delicate mechanisms in their ears caused by ageing or by exposure to excessive noise either at the workplace or in their leisure time

So let’s look at the facts behind the current epidemic of hearing loss which primarily affects the elderly population, but is also an increasing issue among young people.

According to Action on Hearing Loss, formerly the Royal National Institute for Deaf people, hearing loss affected 10 million people in the UK in 2011 but that number is set to rise dramatically to around 14.5 million people in 2031. In 2013, it is estimated that the UK economy lost more than £24.8 billion due to hearing loss.

Although people past retirement age make up the majority of people with hearing loss, more than a third of the total are people of working age. An American study published in the Journal of the American Medical Association in 2010 found that the number of young people aged between 12-19 who suffered from hearing loss increased significantly from 14.9 per cent in 1988-1994 to 19.5 per cent in 2005-2006.

And what is the cause of this dramatic increase? There are several major factors. The main factor behind the epidemic is simply that people are getting older, and hearing ability deteriorates with age. However, exposure to loud sounds is the main preventable cause of hearing loss. Today, stricter health and safety legislation means that no one should be exposed to persistent noise of 85 dBA or higher in the workplace without ear protection (although people differ in their sensitivity, and the truly safe limit for all people may be closer to 75 dBA).

According to several major studies, as age-related hearing loss worsens, so does the risk of developing dementia. People who only have mild hearing loss are twice as likely to develop dementia but those with moderate hearing loss have a three-fold risk increase and those with severe hearing loss have five times the risk of developing dementia compared with someone who can hear well.

The reason for the link is not known although there are theories. One is that people who cannot hear well gradually become socially isolated – a known risk factor for dementia.

The second group are the young who spend many hours a day on their MP3 players and enjoy going to live gigs where the volume is turned up to max. We carried out a study in Manchester and measured noise levels in nightclubs in the city. The typical output was around 100 dBA which is loud enough to damage the delicate cilia in the ear, literally flattening them by sound waves like corn in a gale.

Some may try to litigate. But a more likely scenario is that they will become major users of private medical insurance or the NHS, putting more strain of already-stretched health services. Not a good result and one which we should try to avoid in future by educating people about the risks and bringing in tougher rules about safe noise levels for manufacturers of personal music systems and event organisers.