Hearing loss is a common condition that affects people of all ages, including children. Hearing loss in children, if untreated, can significantly impact development.
Children rely heavily on hearing to acquire speech and language. Without intervention before 6 months of age, hearing loss can lead to delayed speech, poor vocabulary, and difficulties learning language. This in turn impacts reading, writing, and social skills.
Hearing loss also makes it hard for children to follow classroom instruction, leading to struggles with academics. Behavior and emotional issues may arise as well.
Early identification, hearing aids, therapy, and support services are critical to prevent these negative effects and ensure children with hearing impairments develop strong communication abilities.
Here are the main causes of hearing loss in children:
Congenital Causes
Between two and three out of every 1,000 children are born with hearing loss in one or both ears; 90% of them are born to parents with no hearing problems. Congenital causes refer to hearing loss that is present at birth due to genetic factors or conditions and complications during pregnancy or childbirth. Some examples include:
Genetic mutations
Mutations in genes passed down from parents can cause hearing loss in babies. Some common genetic conditions linked with hearing loss include Waardenburg syndrome, Usher syndrome, and Pendred syndrome among others. These syndromes involve mutations in genes important for normal ear development and hearing.
Ear deformities
Malformation of the outer ear, middle ear, or inner ear structures can prevent sound from passing efficiently through the ear and reaching the inner ear and brain. Examples include microtia (underdeveloped outer ear) or atresia (absence of the ear canal). The ear canal may be narrow or blocked. The middle or inner ear structures may be absent, malformed, or function abnormally.
Low birth weight
Babies born prematurely or weighing less than their peers are at higher risk of hearing loss. The underdeveloped ears are more vulnerable to damage. Premature babies may lack a fully formed outer and middle ear and have an underdeveloped auditory nerve.
Birth complications
Lack of oxygen, trauma, or mechanical injury during a difficult delivery can damage the baby’s hearing organs and nerves. Common causes include prolonged labor, prematurity, respiratory distress, jaundice, and mechanical ventilation. The trauma can lead to inner ear hemorrhaging.
Acquired Causes
Acquired hearing loss occurs later in childhood, after birth, due to various health conditions, medications, injuries, or loud noise exposure. Some common acquired causes are:
Ear infections
Frequent ear infections in early childhood, such as otitis media or glue ear, can cause temporary or permanent hearing loss if left untreated. Fluid buildup in the middle ear muffles sound transmission. The fluid prevents the middle ear bones from vibrating properly in response to sound.
Medications
Certain strong medications like aminoglycoside antibiotics and chemotherapy drugs are toxic to the inner ear and can damage hearing over time. These ototoxic drugs damage the hair cells in the cochlea that detect sound vibrations.
Head trauma
Injuries like skull fractures, head wounds, or whiplash injuries can lead to sensorineural hearing loss by damaging the inner ear and auditory nerves. The trauma can rupture the ear drum or dislocate the small middle ear bones.
Noise exposure
Loud noises from toys, concerts, traffic, or personal audio devices can exceed safe decibel levels and gradually cause noise-induced hearing loss over time. Children’s ears are especially vulnerable. The excessive noise can rupture eardrums or damage the hair cells in the inner ear.
Illnesses
Serious illnesses like meningitis, measles, mumps, or even the common cold can lead to hearing loss by infecting the ears. Chronic illnesses like diabetes or thyroid disorders can also impact hearing over time. These diseases can inflame and damage the middle and inner ear structures.
Family history
Around 30% of childhood hearing loss is hereditary. Having a close relative with hearing loss puts a child at higher genetic risk. There are hundreds of genetic mutations that can cause hearing loss and many run in families.
Early Detection and Treatment
The key to minimizing long-term effects of hearing loss in kids is early identification and intervention through newborn hearing screening, regular hearing tests, and careful monitoring of speech/language milestones. All 50 states have implemented newborn screening programs that test babies for hearing loss right after birth. Screening allows diagnosis and treatment to start before 6 months of age, which is critical for developing speech and language skills.
Treatment options include hearing aids, cochlear implants, assistive listening devices, speech therapy, and special education services. Hearing devices like hearing aids and cochlear implants amplify and transmit sound to the auditory nerve. Assistive devices like FM systems or captioning help children access classroom instruction. Speech therapy and auditory training help kids learn to listen, process, and speak language. With appropriate support, children with hearing loss can develop good communication skills.
Preventing Hearing Loss in Children
While the congenital causes of childhood hearing loss are unavoidable, some acquired causes can be prevented through safety measures like:
- Vaccinating against illnesses like meningitis and measles that can lead to hearing loss through inflammation and nerve damage in the ears.
- Treating ear infections promptly with antibiotics to clear fluid buildup and prevent permanent damage of the middle and inner ear structures.
- Limiting noise exposure from audio devices, concerts, machinery, etc., by using volume-limiting headphones and avoiding extremely loud environments that exceed safe levels.
- Wearing protective ear wear like earmuffs and earplugs around any anticipated loud noises to prevent noise-induced hearing loss.
- Avoiding head trauma by using proper safety gear like helmets in high impact sports to prevent injuries that could damage the ears.
- Monitoring side effects of necessary medications like aminoglycosides that are toxic to ear structures and can cause permanent damage.
- Promoting healthy pregnancies and safe deliveries of babies to minimize risk of congenital hearing loss from complications.
Raising awareness and promoting early detection, treatment and prevention of hearing loss gives children the best chance at healthy hearing and communication development. With a coordinated effort between families, schools, doctors, and speech professionals, children with hearing impairments can thrive.