[Kim Jaeho's Life Story]<244> Can Hearing Loss Be Prevented?

The most serious ear disease is hearing loss, commonly known as hearing impairment, where hearing is damaged and sounds cannot be properly perceived. The majority of patients suffer from inflammation caused by bacterial or viral infections, with otitis media?inflammation of the middle ear?being the most common. Otitis media generally recovers except in cases leading to partial hearing loss, whereas hearing impairment does not recover well unless the underlying cause is eliminated.

According to the World Health Organization (WHO), nearly 20% of the global population, over 1.5 billion people, currently suffer from hearing loss, among whom 430 million have hearing disabilities. Worldwide, 34 million children have hearing disabilities or hearing loss, 60% of which are due to preventable causes, and about 30% of people aged 60 and older experience hearing loss.

In South Korea, where the population aged 60 and above is steadily increasing, many people suffer from hearing loss, and this number is expected to rise further. Therefore, efforts to prevent and treat hearing loss are urgently needed. The number of patients receiving treatment for hearing loss did not exceed 600,000 until 2018, maintained around 650,000 in 2019 and 2020, but surged to 740,000 in 2021.

Sound travels through the ear, eardrum (tympanic membrane), cochlea, and nerves to reach the brain for recognition. Difficulty in hearing indicates a problem somewhere along this pathway. The causes of hearing loss are diverse and are broadly classified into conductive hearing loss and sensorineural hearing loss, depending on which part of the sound recognition process is affected.

Sound is collected by the auricle, passes through the external ear canal, and causes the eardrum to vibrate. The vibration of the eardrum induces vibrations in the ossicles attached to it, which are then transmitted to the cochlea. Problems occurring in this sound transmission process up to this point are called conductive hearing loss. Causes of conductive hearing loss include external ear infections, blockage by earwax, damage to the eardrum, otitis media with effusion (fluid in the middle ear), chronic otitis media, and dysfunction of the ossicles.

The cochlea converts the received sound vibrations into nerve signals using sensory nerve cells and transmits them to the brain via nerves. Problems occurring in this process are called sensorineural hearing loss.

Hearing loss increases with age, and nearly half of the population aged 75 and older are known to experience hearing difficulties. Hearing problems not only cause inconvenience in daily life but can also lead to depression, frustration, social withdrawal, faster cognitive decline, and increased risk of dementia. People with hearing loss may be mistakenly perceived by others as confused, unresponsive, or uncooperative.

Treatment for hearing loss varies depending on the cause. Conductive hearing loss, where external sounds are not properly transmitted to the cochlea, is treated with medications such as antibiotics and surgeries like those for otitis media. Sensorineural hearing loss, caused by problems in converting sound vibrations into nerve signals and transmitting them to the brain, is treated with medication depending on the cause.

If hearing cannot be restored to normal by any treatment, hearing aids are used. Hearing aids amplify sound to help people with hearing disabilities hear something, but their effectiveness is limited for those with severe hearing loss. Although hearing loss is treated in various ways, many people around us live with discomfort because their hearing does not fully recover.

So, what is the best way to prevent hearing loss? As with all diseases, prevention is undoubtedly the best approach, and preventive measures also greatly aid recovery after onset.

WHO estimates that 50% of hearing loss can be prevented through public health measures. These include wearing protective equipment such as earplugs to avoid exposure to loud noises and music, early screening and treatment, avoiding harmful medications, and strengthening vaccination and hygiene programs to prevent hearing loss caused by complications from diseases such as measles, meningitis, rubella, and mumps.

However, while these preventive measures are quite effective, how much can they reduce hearing loss alone? The process of sound entering the ear, being transmitted to the brain, and recognized involves numerous cells, and it is important to note that within every cell, countless genes are activated as needed to perform their unique functions.

According to scientific research, among the 6 billion DNA molecules inside a single cell, hundreds of thousands are damaged daily during our lifetime. The body's top expert in the form of genes restores damaged DNA to its original state.

However, if the top expert within our genes has lifestyle habits that interfere with gene activity, the amount of damaged DNA increases, and the repair of damaged DNA is not properly carried out, leading to numerous diseases, including hearing loss.

Preventing and healing hearing loss is no different. Abandoning harmful lifestyle habits that damage genes or hinder gene activation and creating a good environment where genes can work enthusiastically?known as Newstart (refer to Life Story Part 6)?can be greatly helpful.

Jaeho Kim, Independent Researcher