As children grow, hearing ability is vital to developing speech and language skills. Traditionally it has been difficult to discern a hearing difficulty with children under two years of age, until it became apparent that speech abilities were delayed.
It has been shown, however, that if early detection of a hearing issue can be diagnosed prior to six months of age, speech impairment and delays can be drastically reduced. For this reason, infant hearing screening is now common in US hospitals and children with hearing loss can be identified and treated in infancy.
Research studies have indicated that between 5 children in 1,000 may suffer from hearing loss, most diagnosed between the ages of three and 17 years old, and there may be as many as 1.4 in 1,000 newborns with hearing impairment at birth.
How Can Children Have Hearing Loss?
Childhood hearing loss has become much more prevalent in recent years due to environmental noise. A 2013 CDC study estimated that at least 12.5% of children and teens ages six to 19 have permanent hearing damage because of noise exposure.
Parents, guardians, teachers and doctors need to be aware of the signs of hearing loss in children, because early diagnosis and treatment is key to arresting hearing loss and preventing lifelong damage to hearing. Undiagnosed hearing loss in young children can cause developmental delays and substantial emotional issues for children that can be difficult to overcome even into adulthood.
Congenital Hearing Impairment
Some hearing damage is already present at birth: this is called congenital hearing loss. There are many causes of congenital hearing loss, with both genetic and non-genetic factors.
Non-genetic factors may include:
- Premature birth with a birth weight of less than 3 pounds or the necessity of respiratory drugs.
- Maternal diabetes.
- Maternal alcohol or drug abuse.
- Birth complications, including the presence of diseases such as rubella, herpes or another infection.
- Lack of oxygen at birth or need for a blood transfusion at birth.
- A brain disorder or nervous system issue.
- Use of ototoxic medication by the mother during pregnancy—such as antibiotics or over-the-counter medications like NSAIDS (ibuprofen or acetaminophen).
Non-genetic factors account for about 25% of congenital hearing loss, and genetic factors caused by heredity cause over 50% of hearing loss in children. Sometimes this hearing loss is evident at birth, and sometimes it is revealed later in life.
Genetic Hearing Loss Factors May Include:
- Autosomal Dominant Hearing Loss, which accounts for approximately 15% of genetic hearing damage, is acquired because one parent carries a dominant gene for hearing loss and passes it to the child. The parent may or may not manifest hearing loss.
- Genetic syndromes such as Waardenburg Syndrome, Down Syndrome, Usher Syndrome, Teacher Collins Syndrome Crouzon Syndrome or Alport Syndrome may cause hearing damage at birth.
- Autosomal Recessive Hearing Loss is the most common genetic congenital hearing damage cause, accounting for about 70% of genetic hearing impairment. In this case, neither parent has hearing loss, but both parents carry a recessive gene for hearing loss that are passed to the child. Most parents are not aware they carry this recessive gene and are thus astonished when the child displays hearing damage for this reason.
In some cases, the reasons for infant hearing loss are unknown, making up the balance of the hearing loss cases at birth.
Acquired Hearing Impairment
Many children are not born with hearing damage but attain it during childhood. Reasons for acquired hearing loss can be:
- Taking ototoxic medications
- Serious head injury
- A perforated eardrum
- Infections such as measles, mumps, whooping cough or meningitis
- Exposure to second-hand smoke
- Untreated or frequent ear infections
- Exposure to loud noises (which cause noise-induced hearing loss)
- Otosclerosis or Meniere’s diseases (progressive)
Temporary Hearing Damage
Fluctuating or transient hearing impairment in childhood can also impair language development and speech. Temporary hearing loss can be caused by ear infections, and at least 75% of children have had this type of ear infection by the time they reach 3 years of age.
Transient hearing loss caused by an ear infection happens when fluid blocks the vibrations of the middle ear bones and muffle sound. Because it is usually temporary, this type of hearing loss often resolves itself with the healing of the ear infection, though if ear infections are frequent or untreated, permanent damage can occur.
If you are concerned a child in your life may have hearing damage, it is crucial to make an appointment for a hearing screening to determine the best course of action. Hearing damage is treatable, especially if caught early, but is not reversible.
Here at California Hearing Center we are committed to your hearing health. Call us today to set up an appointment for a hearing screening.