Hearing loss - what are the possible causes?

The possible causes of hearing loss

Why do I hear worse than other people? What are the causes of hearing loss? Our ancestors must have asked themselves this question in prehistoric times - for them, good hearing was a matter of life and death: if you couldn't hear the rustling grass, you didn't suspect the sabre-toothed tiger was sneaking up on you.

Even today, our ears fulfil this protective function, warning us, for example, of a suddenly approaching car in traffic.

However, in contrast to earlier times, we now know much more about our hearing organ - thanks to enormous advances in modern medicine, the possible causes of hearing loss are largely known.

The following factors can cause hearing loss:

• Noise

The louder and the longer sounds affect the ear, the higher the risk of permanent hearing loss - the causes can be loud music or occupational noise. From toddlers to pensioners, people of all ages are affected.

• Age

Signs of wear and tear, genetic factors, age-related diseases and the cumulative effects of noise over the course of a lifetime: All this increases the risk of hearing loss in old age.

• Diseases, accidents, foreign bodies

Permanent hearing loss can be caused by a disease, or by injuries that damage the hearing organ. Sometimes earwax or foreign objects block the ear canal.

• Inherited hearing loss

About 0.1 to 0.3 percent of all children are born with hearing loss or even deafness. This makes hearing impairment the most common congenital disease.

To summarize: Hearing loss has causes that either occur in the course of life or are congenital - and can lead to permanent or temporary hearing loss.Important for those affected and their relatives: Around 15 million people in Germany hear worse than normal. So anyone who notices a deterioration in their hearing is not alone. However, the causes of hearing loss should be clarified as soon as possible. The first point of contact is an ear, nose and throat specialist. Depending on the diagnosis, they will initiate the appropriate treatment or recommend a visit to a hearing care professional. In many cases, they can completely compensate for the hearing loss with the help of modern, almost invisible hearing aids.

Hearing protection, hearing aids or medication? Anyone who knows the causes of hearing loss also knows which countermeasures are the right ones. To reduce the risk of hearing loss - or to restore a reduced hearing performance.

 Causes of hearing loss in old age

Ear, nose and throat doctors advise having your hearing checked every two years from the age of 50, as the risk of hearing loss increases with age.

Prof. Dr. med. Hans Behrbohm, ENT Chief Physician,
Park-Klinik Weißensee in Berlin

"Like everything else in the human body, the ear is subject to certain signs of wear and tear. As we age, our hearing, especially for the higher notes, diminishes. "

Those affected find it increasingly difficult to understand a conversation or to follow the course of the conversation.

Statistics show that the percentage of people with hearing impairment increases rapidly with age:

• Among 40 to 49 year olds, only 6 percent are affected.
• Among those aged 50 to 59, the figure is already 25 percent.
• Among 60- to 69-year-olds, the figure is 37 percent.
• Among those aged 70 and older, the figure is 54 percent.

What are the exact causes of hearing loss in old age? According to medical experts, this is not yet clearly understood. 

"It's probably a combination of different physical changes," Behrbohm explains. "These can be deposits of metabolic products in cells or loss of elasticity of certain tissues. It's also possible a lifetime accumulation of hearing-damaging events, such as prolonged exposure to noise, stimulants like alcohol and cigarettes, and environmental toxins and middle ear disease."

A remedy is provided by individually fitted hearing aids, which compensate for hearing loss and are already prescribed by the ENT doctor on prescription without co-payment.

Hearing loss with cold

A cold is not always harmless: some viruses can lead to middle or inner ear infections. In addition to symptoms such as unpleasant earache and fever, hearing loss is also common.

Hearing loss caused by a cold is usually due to the fact that the so-called tympanic cavity in the ear is infected - and the ossicles located there can only incompletely transmit the sound picked up by the eardrum to the inner ear.

Doctors therefore usually speak of a conductive hearing loss when hearing loss is caused by a cold.

Hearing loss - causes at work

Anyone who works in a noisy workplace must wear hearing protection. There are good reasons for this legal regulation: Hearing loss is one of the official occupational diseases - and tops the list of most recognised cases in this country. 

This is usually referred to as noise-induced hearing loss, which is caused by long-term (chronic) exposure to noise.

The severity of noise-induced hearing loss varies depending on:

• Noise duration
• Volume (level)
• the temporal distribution of the daily noise exposure (continuous exposure or interruption by breaks)
• individual factors

So-called impulse noise is considered particularly dangerous. It is triggered by short and loud bangs or noises, for example when a shot is fired or a New Year's Eve firecracker explodes.

The sound pressure responsible for the volume is measured in Pascal (pa, N/m2). The pitch (frequency), i.e. the number of vibrations per second, is measured in Hertz (Hz).

"The noise scale increases logarithmically," says hearing specialist Behrbohm. "This means that an increase of 10 dB corresponds to a doubling of the perceived loudness.

In Germany, the Workplace Ordinance and the Noise and Vibration Occupational Health and Safety Ordinance apply. Both regulations govern noise protection in the workplace and are intended to protect employees from health risks caused by occupational noise.

At average sound levels of 85 dB (A) and above - equivalent to a jackhammer ten metres away or a passing train - employers must provide their employees with hearing protection.

Occupational groups at risk include, for example:

• ground handler
• Road construction workers
• Discotheque staff
• Farmers and farm workers
• Brewery employees
• Orchestral Musicians
• Teachers and kindergarten teachers

Causes of hearing loss in children and adolescents

Whistles, loud toys or a middle ear infection: In most cases, the causes of hearing loss in children and adolescents are recreational noise or illness.

According to a study by the German Federal Environmental Agency, about 13 percent of children in this country have a hearing loss of more than 20 dB HL (HL="Hearing Loss").

For young people, regular listening to loud music through headphones, in discos or at concerts sometimes has dramatic consequences. 

"This is especially true for music louder than 100 dB," ear, nose and throat specialist Behrbohm knows. "It can cause the sensory cells in the ear to perish. The sound is still picked up, but the sensory cells are no longer able to process it."

Since noise damage cannot be cured, prevention is particularly important. The following always applies: If the ENT doctor diagnoses noise-induced hearing loss, he prescribes hearing aids.

Hearing aid acousticians, so-called pediatric acousticians, who are specially trained for the needs of children and adolescents, find out which model is suitable. The fitted hearing aids compensate for the hearing loss - and are almost invisible. This is an important factor, especially for young people going through puberty.

Hearing loss from birth

Some children are born with hearing loss. Inherited hearing loss is then a possible cause - about half of the cases are based on such a genetic cause. However, it is often not possible to determine the exact cause of hearing loss in newborns.

Early diagnosis and treatment of affected children is important, as hearing loss can have a massive impact on their development. This is where the Newborn Hearing Screening (NGHS), which is part of newborn screening and aims to detect hearing impairment at an early stage, can help.

Here too, depending on the age, ENT doctors prescribe hearing aids, which parents select together with a trained hearing care professional so that they are optimally adapted to the needs of the children.

Otosclerosis as a trigger for hearing loss

Otosclerosis is a gradual hearing loss. In this disease, the tiny stapes bone in the ear is most often affected.

Women fall ill twice as often as men. As triggering factors, experts discuss, in addition to genetic factors, a local infection with the measles virus and hormonal changes, such as during pregnancy.