Newborn Hearing Screening, Pediatric Issues, and More : Interview with Anne Marie Tharpe, PhD
Douglas L. Beck, AuD, speaks with Dr. Tharpe about early hearing loss detection and intervention, “lost at follow-up” challenges, and more.
Academy: Hi, Anne Marie. Thanks for meeting with me today. As always it’s a pleasure speaking with you.
Tharpe: Hi, Doug. Thanks for the kind invitation.
Academy: For those less familiar with your work, I’d like to mention that in addition to being a professor at Vanderbilt, you have been extraordinarily involved with pediatric issues. For example, in the upcoming (2009) consumer-based Academy Web site, I’m delighted to announce that you and I co-authored much of the newborn hearing screening information—along with significant help from the Academy’s Publication Committee.
I know you’ve worked on the original published pediatric management and diagnostics guidelines from the Academy (2003) and, you are now working on the new Academy Task Force to develop pediatric Amplification guidelines (2009/2010). You were also involved with ASHA’s birth to age five years assessment guidelines (2006) writing group. I believe you also worked on and indeed chaired the combined ASHA and Centers for Disease Control (CDC) “Lost to Follow-Up” Committee regarding newborn hearing screenings, and so clearly, you’re way deep into pediatric issues! So, let’s start with pediatric hearing screenings versus early hearing detection and intervention (EHDI). What’s the status of newborn hearing screenings?
Tharpe: Well, that’s a long story, but the current numbers indicate that in the United States, we are screening some 95 or 96 percent of all newborns, and so that’s excellent. We’ve come a long way in just 25 years. In fact, the Academy news article addressed the latest numbers as reported by Hayes. So, in many respects, we, as a profession should be very proud of this. However, there’s a lot more to EHDI than just the newborn screening.
Academy: Yes. I believe the numbers I’ve seen indicate that perhaps half of all the newborns screened end up being “lost to follow-up.”
Tharpe: That’s about the same as the numbers I’ve seen and this is clearly an area we need to address and devise protocols that will better serve the infants who fail screenings. As you know, Doug, sometimes these children do receive follow-up, but they do so in other clinics without their records being linked to the state newborn screening program. So, some of these babies may be getting diagnostic and perhaps intervention services, but the state doesn’t know about it, and so they are categorized as “lost to follow-up” but are really “lost to documentation.”
Academy: And, while we are on screenings, I always like to add that when we screen with OAEs only, we do have the opportunity to miss auditory neuropathy. Furthermore, the most recent numbers form Seminars in Hearing (2008) stated that some 25 times more children have hearing loss in elementary school, than those flagged via newborn screenings at birth, because the screenings may miss mild hearing losses, as well as those with cytomegalovirus (CMV), which might develop significant hearing loss after birth, but before starting school, as well as other disease processes, such as otitis.
Tharpe: Exactly right. About 40 percent of screening programs do not collect information about risk indicators for hearing loss; therefore, parents of babies in those programs might not know that their babies are at risk for late-onset or progressive hearing loss. And, the newborn screening itself is just one component of the EHDI program. Certainly, screenings in isolation from diagnostic follow-up, on-going monitoring, and management are not useful, and as you mentioned, just under 50 percent of these children are lost to follow-up. Of course, this figure is likely to include those babies who are “lost to documentation,” so one way to combat this is to make sure the diagnostic and management audiologists are communicating with the state newborn screening program.
Audiologists in clinics and pediatric hospitals sometimes don’t get involved in the paper-flow and administrative details of documenting these children, but I think we can resolve many of the “lost” babies if the audiologists and other interventionists involved with diagnostics and rehab make sure the state finds out about the child’s progress when the paperwork and referral letters go out.
Academy: That seems entirely too easy! Nonetheless, I know you’re right. Even if we just make sure to send a quick letter to the screening center thanking them for the referral, that removes the child from the “lost” category.
Tharpe: Sure, although to properly document the progress that children can make in EHDI programs, it is desirable for states to receive specific information about their follow-up and management. Another issue is the ability of the system to handle the data and paper-flow particularly when the child and the diagnostic center are in neighboring states. Currently, only 17 percent of EHDI programs are linked to other data systems like vital statistics, metabolic screenings, etc. (White, 2008). Another piece of this problem is that some families actually choose not to follow up, such as the family who’s been told that their child has a mild or unilateral hearing loss.
Academy: Yes, I understand. I’m sure that in some of these cases, when we present the information as somewhat “minimal” we may accidentally lead the parents down the wrong road. For example, in the situation you just mentioned, I recall Fred Bess’s publications from years ago that showed when a child has a unilateral hearing loss, he or she is 10 times more likely to repeat a grade, than is the child with normal hearing in both ears.
Tharpe: Yes, and in addition to Dr. Bess’s work, other studies have confirmed those findings. We also don’t know exactly how many children acquire or have progressive hearing loss after birth, as opposed to how many might have been missed at their newborn screening. We know from work by Johnson and colleagues (2005) that the majority of the losses that are missed by newborn screening programs, are of mild degree. Furthermore, in the May, 2008 Seminars (Editors Eichwald and Gabbard), which you mentioned a few moments ago, they also reported the prevalence of hearing loss in children. Typically, we think of 1 to 3 children per 1,000 as having severe-to-profound hearing loss, but when we look at representative numbers of all the children with mild bilateral sensorineural hearing loss, there are approximately 10 to 15 children per 1,000, and then if you add in the children with unilateral hearing loss, there’s another 30 to 56 children per 1,000.
Academy: Yes, those numbers are staggering, and to my way of thinking, that indicates that some 7 to 8 percent of all school-aged children likely have some demonstrable permanent hearing loss.
Tharpe: Exactly, that’s why we need to be sure to not rest on the screening successes, and work diligently to make sure we address the rest of the EHDI program components including amplification and intervention needs. So to me, one of our primary goals is to make sure physicians and parents understand that just passing the hearing screening at birth does not rule out all degrees of hearing loss or late-onset hearing loss. That is, as you mentioned, 25 times more children have hearing loss as they enter school than they did at birth, so we need to make sure physicians and parents don’t assume, “My child passed the newborn hearing screening at birth, so hearing is not a problem.” We need them to know that most babies with hearing loss will pass the screenings, because the hearing loss might not be apparent or present at that time, but it can develop in the early years.
Academy: And so we also need screenings at school, and perhaps at about age 2 or 3 years, too. Tharpe: Absolutely. Based on the American Academy of Pediatrics periodicity schedule, children receive a global screening at 9, 18 and 24-30 months. If a child does not pass the speech-language portion, he or she is to be referred to an audiologist and speech-language pathologist immediately for further evaluation. These screenings should assist in identifying late-onset and progressive hearing loss after the newborn period.
Academy: Anne Marie, it’s a joy to speak with you. Thanks so much for your time and expertise.
Tharpe: My pleasure, Doug. Thanks you for your time, too.
Anne Marie Tharpe, PhD, is a professor at Vanderbilt Bill Wilkerson Center, Department of Hearing & Speech Sciences in Nashville, TN.
Douglas L. Beck, AuD, Board Certified Audiologist, is the Web content editor for the American Academy of Audiology.