COMMUNITY PEDIATRICS: Hearing impairment

November 1, 2014

Because even mild hearing impairment hinders children's verbal and social development, Dylan K. Chan, MD, PhD, urged attendees to screen newborns for cytomegalovirus (CMV)-the culprit in 15% to 20% of all congenital hearing loss (HL)-within 21 days of birth when indicated.

 

Because even mild hearing impairment hinders children's verbal and social development, Dylan K. Chan, MD, PhD, urged attendees to screen newborns for cytomegalovirus (CMV)-the culprit in 15% to 20% of all congenital hearing loss (HL)-within 21 days of birth when indicated. His presentation, “Child Hearing Impairment: Therapeutic Breakthroughs for a Silent Epidemic,” also stressed the importance of making families and communities aware of preventive strategies for HL at all ages.

Regarding CMV, Chan recommended that pediatric care providers retest within 2 weeks the hearing of any infants who fail a newborn hearing screening. Babies who fail this screening should undergo testing for congenital CMV before 3 weeks of age (the state of Utah has made these requirements law). Those who test positive require a full audiology examination as soon as possible.

On the therapeutic horizon, a 6-month course of oral valganciclovir provided significant improvement or stabilized normal hearing (odds ratio, 1.02-6.91) at 24 months' follow-up in a large multinational phase III trial (Kimberlin DW, et al; in press).

As for preventing HL, Occupational Safety and Health Administration (OSHA) guidelines suggest no more than 8 hours of unprotected exposure at 90 dB, but just 15 minutes or less at 115 dB, the level of a rock concert. Even ambient noise in the neonatal intensive care unit can pose problems for infants, Chan noted. For hearing protection, earplugs can provide up to 30 dB attenuation, turning a dangerous din into comfortable sound. Similarly, noise-canceling earbuds allow listeners to use lower volume settings on digital devices.

Community awareness boosts early intervention efforts, such as use of individual family service plans for preschoolers or, for school-aged children with HL, speech-language therapy, preferential seating, and perhaps sign-language instruction.

Among treatments for HL, hearing aids are the most effective approach for patients of all ages and for all types of HL. Cochlear implants, in particular, can help patients aged older than 1 year with severe to profound HL to develop normal speech and awareness of the aural environment, provided families have appropriate support and expectations.

Dylan K. Chan, MD, PhD, is assistant professor, pediatric otolaryngology-head and neck surgery, University of California, San Francisco.

 

 

 

In Dr. Chan's presentation, what jumps out is the number of babies lost to follow-up. Data show that in California, of the 10,000 babies who fail the newborn hearing screen, about 5% do not get further testing; 800 newborns are diagnosed with congenital sensorineural hearing loss (SNHL) each year and referred for further outpatient testing. Of these infants, 100-more than 12%-are lost to follow-up and do not get early intervention that is likely to preserve language.

That is where pediatricians, parents, and audiologists need to set up a partnership, so that those infants diagnosed with HL can get the treatment they need, and the infants with a high suspicion for HL are also properly diagnosed. This is a place where we can make a real difference.

The other key finding that pediatricians are unlikely to know about is the recommendation for CMV testing at 3 weeks of age if a newborn is diagnosed with SNHL, because it appears that there is treatment outside of hearing aids that can minimize the severity of hearing loss. A study showed that a 6-month course of valganciclovir minimizes hearing loss and increases the odds of hearing improvement. Other multi-institutional randomized controlled trials of valganciclovir are in progress.

The other very important issue that Chan discussed is the impact of high-volume noise. That tends to affect the middle childhood years, when you have kids listening to iPods and other such devices, often at 100 dB, and the people around them are not aware of the high-volume noise. Listening to that level of noise is likely to result in long-term hearing loss.

Hearing is not a topic that pediatricians always address with parents of middle schoolers and high schoolers, but it's certainly something we should be discussing as children increasingly get iPods, iPhones, and other devices for both communication and entertainment. We talk about screen time in terms of TV, video game, and computer usage, which should be less than 2 hours daily. However, we don't necessarily talk about noise pollution and use of music devices that might affect a child's hearing, especially because guidelines from OSHA have established that listening to something at 100 dB for more than 2 hours per day is likely to damage one's hearing.

Ganga L. Srinivas, MBBS, is assistant professor of pediatrics, Medical University of South Carolina, Charleston.

Mr Jesitus is a medical writer based in Colorado. He has nothing to disclose in regard to affiliations with or financial interests in any organizations that may have an interest in any part of this article.