While infant hearing loss is more frequently screened for and identified in the United States than it was a decade ago, the challenge has now shifted toward the delivery of timely intervention when it's needed, according to a report from the Centers for Disease Control and Prevention.
“Now that [more than] 95% of U.S. infants can be documented as having their hearing screened, remaining challenges include ensuring timely diagnostic evaluation for those who did not pass the screening and enrollment in early intervention for those with diagnosed hearing loss,” wrote M. Gaffney and colleagues from the National Center on Birth Defects and Developmental Disabilities at the CDC.
Early Hearing Detection and Intervention (EHDI) programs established in all states and U.S. territories recommend that infants undergo hearing screening no later than age 1 month, diagnostic and audiologic evaluation no later than age 3 months for infants who do not pass the screening, and enrollment in early intervention no later than age 6 months for infants with diagnosed hearing loss.
But an analysis of CDC and EHDI surveillance data from 1999 through 2007, while showing an increase in screening from 47% to 97%, also found that 46% of infants who did not pass the final or most recent screening in 2007 were either lost to follow-up or lost to documentation (LFU/LTD). When the numbers are evaluated slightly differently, only 61% of infants diagnosed with hearing loss in 2007 were enrolled in early intervention by the age of 6 months (MMWR 2010:59;220-3).
“EHDI programs such as those in Massachusetts and Colorado, which often actively follow up with families and providers and reported LFU/LTD in 2007 of 5.6% and 6.4%, respectively, are good examples for other programs trying to improve overall follow-up rates,” the authors wrote.
The national 2007 LFU/LTD rate of 46% is an improvement over the 2005 rate of 64%, especially considering that more infants were screened and diagnosed with hearing loss in 2007. Indeed, while 52% of infants were screened and 56% of those diagnosed with hearing loss in 2000, 97% were screened and 42% were diagnosed in 2007.
The CDC report outlines its three most significant limitations: The methods and definitions used in data collection differed over the course of the decade, limiting comparability; some states and territories could provide only limited data; and EHDI programs are not designed to detect mild hearing loss below the threshold of 30-40 dB or progressive or late-onset hearing loss.