Sir Patrick Leigh Fermor - traveller, war hero and writer - works his way through hearing aids and spectacles as quickly as most people lose umbrellas. Leigh Fermor's problem with hearing aids is that, although he is 93, he is an inveterate swimmer in the Aegean. Unfortunately, he usually forgets to remove them until reminded by a sudden singing and buzzing in his ears.

Leigh Fermor had attended several schools before being expelled from the King's School Canterbury for having rather too close a relationship with the daughter of the local greengrocer. Despite this, he now enjoys a cordial relationship with the school and last year was asked to open his rebuilt old house.

While attending a London crammer after King's, he took the evening off, went to a night club and by chance discovered the allure of Byron and the Byzantine world. It all sounded very exotic compared with relentless cramming and he immediately left Britain on a four-year walk around Europe. He then returned to Moldavia and settled down with a Moldavian princess.

As soon as the Second World War was declared, Leigh Fermor volunteered for the Irish Guards and later served in intelligence with the resistance in Crete. His most famous exploit was to kidnap the German commander-in-chief and smuggle him via a British submarine to a prisoner of war camp, but his hearing must have been exposed to repeated explosions and gunfire.

Some degree of deafness is so common in ex-servicemen that, when examining men's hearing tests, it is possible to make an informed guess about which of the patients have served in the Army - even if it was only on the ranges of Germany or Britain while doing National Service. Deafness is not as obvious as blindness, but can be almost as disabling. It is the most common reason for those who have served in the current Afghan campaign to have been regraded as being unfit for future frontline service.

As with old soldiers, so with civilians exposed to excessive noise. However the noise-induced deafness has been acquired, whether in a battle, on a range, the dance or factory floor, whether clubbing or fighting, it makes no difference to the course of the disability.

At the time that a person's hearing was subjected to a barrage of noise, it may have resulted only in a day or two of deafness, usually accompanied by a whistling or other extraneous noise in his or her ears. But if the noise has been loud or persistent enough to cause immediate damage, the future seeds of deafness may have been sown. Years later, the unwise clubber or brave soldier may find that conversation in restaurants, airports and parties is a strain and domestic or office life is regularly interrupted by searches for hearing aids.

The European Union's Scientific Committee on Emerging and Newly Identified Health Risks has included the hazard to hearing presented by MP3 personal music devices. This risk joins that of high-decibel club music. Noiseinduced deafness is now more likely to result from MP3 devices offering a constant plugged-in source of high-decibel music than from gunfire or the clatter and bangs of heavy industry. The Royal National Institute for Deaf People reckons that a fondness for clubs or personal music players of the MP3 type may leave as many as two younger people in three with problems of deafness in later life.

Help is now at hand, in the form of a new high-tech device known as the HearPlus aid for those who are showing the earliest signs of deafness. Usually it is the family and colleagues who first notice deafness and will suggest an aid, whereas a patient dismisses any inability to hear as being no more than evidence that people no longer speak slowly or clearly enough. Few people realise that in early deafness the words in a conversation, although heard, sound jumbled, muffled and the diction poor.

HearPlus devices are designed to be unobtrusive as, in an increasingly competitive world, people don't like to have their deafness advertised because it hints at ageing. A few years ago, a small dispos-able device, the Songbird, was introduced. Like HearPlus, it gave remarkably good hearing but, as it lasted for only a week or two, it proved uneconomic. HearPlus gives hearing an instant boost, is about the size of a jelly bean and, like the Songbird, fits reasonably discreetly into an ear. As HearPlus is battery-powered, it can be used indefinitely - each battery has a life of 114 hours - and in the long term it is less expensive than the Songbird. It has a pre-programmed volume control that changes automatically if the level of sound increases if the environment becomes noisier.

HearPlus improves sound definition, so that someone whose hearing is not quite what it was can once again decipher the general chatter and even hear the high-pitched voices of young children. It is available from David Ormerod Hearing Centres, and selected Boots Opticians. Visit davidormerod.co.uk further information

Explore Health

• Expert Advice

• Health Features

• Mental Health

• Alternative Medicine

• Child Health

• Health Club