Tuesday, March 22, 2011

Can Your Baby Hear Well?

About 2 to 3 out of every 1,000 children in the United States are born deaf or hard-of-hearing. Nine out of every 10 children who are born deaf are born to parents who can hear. 


Unfortunately existing hearing tests do not always catch hearing loss in newborns. According to a new study, one-third of children later treated for deafness with cochlear implants had actually passed the newborn screening.
Thumbnail of chart; click to display full-size image.

The graph on the right shows summary rates of the percentage of newborns screened for hearing loss prior to hospital discharge based on individual State reports posted on the Early Hearing Detection and Intervention Program (EHDI), 1999–2005 Web site. Trend data on newborn hearing screening rates are also available from the DHHS Healthy People 2010 Project (US DHHS, 2006) and from CDC Wonder: Healthy People 2010. Newborn hearing screening rates increase in a linear fashion from 46.1% in 1999 to 82.9% in 2002; thereafter, while the rates continue to increase, the trend line begins to flatten out, reaching 91.5% in 2005. 
So more babies are screened for hearing loss while they are still in the hospital before they go home. 


Yet, as researchers at Children's Memorial Hospital in Chicago found out - by  looking at the records of 127 children who had hearing problems severe enough to be treated with cochlear implants: one-third of these babies had passed the newborn hearing test.

This is not necessarily because the screening is not accurate, but rather the result of the fact that some hearing loss develops slowly. Babies at risk for progressive deafness include those who had cytomegalovirus infections, and those who were in a neonatal intensive care unit.

The earlier children with hearing problems get help, the better they will do at developing language skills. And more testing screens may be needed - Perhaps, even including genetic tests like those developed by Harvard's Center for PErsonalized Genetic Medicine. Or more at-home screening, including iPhone apps or  other inexpensive devices.


References

Nancy Melinda Young, MD; Brian Kip Reilly, MD; Larisa Burke, BA
Limitations of Universal Newborn Hearing Screening in Early Identification of Pediatric Cochlear Implant Candidates. Arch Otolaryngol Head Neck Surg. 2011;137(3):230-234. doi:10.1001/archoto.2011.4


U.S. Department of Health and Human Services. Chapter 28: Vision and Hearing. In:Healthy People 2010 Midcourse Review. Washington, DC: U.S. Government Printing Office, December 2006. (Available at www.healthypeople.gov/


White KR. Research review—Early hearing detection and intervention programs: Opportunities for genetic services. Am J Med Genet 2004; 130A: 29–36.