The following was written by Dr Mary Stoppard and was published in The Daily Mail (14/3/2013).
Does it drive you mad when you’re out for the evening and it’s so noisy you can’t hear a word anyone says? It does me.
You spend the whole time trying to convert sounds into words, then words into sense, leaving you exhausted after a couple of hours.
New research shows that the effort expended by the brain in doing this leaves it tired, so it has no processing power left over.
Just think what it would be like if you spent your whole life straining to catch what other people said – in other words, if you were hard of hearing.
A study at The Johns Hopkins School of Medicine, US has clarified the toll this straining takes. It’s illuminating, but saddening.
The scientists found that there was a close relationship between hearing loss and dementia.
After studying 639 people aged 36-90 for 18 years – none of whom had cognitive impairment at the start – they found those who had mild, moderate and severe hearing loss had two times, three times and five times increased risk of developing dementia compared to people with normal hearing.
The worse the hearing loss, the greater the risk – and this link remained true irrespective of age, diabetes and high blood pressure.
In looking for explanations, the researchers suggested the social isolation that often plagues deaf people was known to be important.
Another possibility is cognitive overload – the brain working too hard trying to hear distorted sounds.
In January, a study of 1,984 adults monitored since 1997, had the same results, but it went a little bit further.
It found people with hearing loss had a 30-40% faster rate of thinking and memory loss than people with normal hearing.
A theory put forward by Cardiff University is that loss of low frequency sounds could be an early warning sign of vascular problems all over the body, leading to hearing loss, heart attacks, stroke and dementia.
This theory is useful because it unites the deafness and dementia with a common cause.
The evidence is sadly irrefutable and is another reason why if you haven’t had your hearing checked recently you really need to. If the outcome of the assessment is that you should accept wearing hearing aids you should consider this as part of your healthy living programme.