Project INCLUDE:

Learning Together About Down Syndrome 

By Dr.  Heather Porter, Boys Town National Research Hospital

A Personal Connection

My youngest sister was born with Goldenhar syndrome, which included being born with hearing loss. Our family learned early signs, but spoken language eventually became the dominant form of communication for my sister, and the role of access to sound moved to center stage. These early experiences inspired me to become a teacher of the Deaf/Hard of Hearing, and later an audiologist.

While studying to become an audiologist, I had opportunities to learn from faculty experts across multiple health disciplines and individuals with neurodevelopmental diagnoses and their families. It was here that I heard first-hand from individuals with Down syndrome and their families about struggles with frequent ear infections, receptive and expressive spoken communication, educational progress, and vocational options. Importantly, I was surprised to learn that hearing was infrequently considered in relation to these issues. And thus, my mission became clear! 

A Little Bit about Down Syndrome

Down syndrome occurs in about 1 in 700 newborns in the United States annually.  The average life expectancy of a baby born with Down syndrome in 1981 (the year my sister was born) was about 25 years of age. Today that average has increased to 60!  Whereas it was once common for individuals with Down syndrome to be institutionalized, thankfully, that is no longer the case.  Currently, most children with Down syndrome are included in part- or full-time in general classroom settings and independence is important to adults with Down syndrome and their families.  

Down syndrome results from triplication (three instead of two) of all or part of chromosome 21, which is why another name for it is Trisomy 21. The name Down syndrome comes from John Langdon Down, who in 1866 first described a connection between the physical features of people with Down syndrome and decreased intellectual ability. Although you may see different historical uses, the currently accepted term in the United States is “Down syndrome,” not “Down’s syndrome,” or “Downs.”  In addition, person-first language should be used. This means that something like, “child with Down syndrome” should be used, not “Down syndrome child.”  

Hearing in Individuals with Down syndrome

There are many health conditions associated with Down syndrome. One of the most common is hearing loss, occurring in up to 80% of individuals with Down syndrome at some point across the lifespan. Although conductive hearing loss is common, and frequently associated with chronic infections or fluid in the middle ear, many people do not realize that sensorineural hearing loss is also more common in individuals with Down syndrome than those without Down syndrome. In fact, hearing loss is often overlooked, misdiagnosed, or under-treated in individuals with intellectual disabilities, including individuals with Down syndrome.  

All of that said, much of what is currently known comes from past studies that reported on people living in institutions or information from medical records. This means that what we have learned from past studies might not apply to adults and children living with Down syndrome today or could be biased toward those who were sick and seeking medical care.  

Project INCLUDE

Our research program at Boys Town National Research Hospital is funded by the National Institutes of Health INCLUDE Project (INvestigation of Co-occurring conditions across the Lifespan to Understand Down syndromE). We liked the acronym so much that we use it for our ongoing studies to improve auditory and vestibular healthcare for people with Down syndrome of all ages, Project INCLUDE!

One of the goals of Project INCLUDE is to overcome the limitations of past auditory and vestibular research and characterize these abilities in a community-based sample of people with Down syndrome of all ages.  This is important information to obtain so people with Down syndrome and their families know what to expect and providers can make evidence-based decisions related to hearing and balance healthcare.

So far, our results show a trend for high-frequency hearing loss that begins at earlier ages for individuals with Down syndrome than what would be expected for the general population.   Whereas increasing high-frequency hearing loss is associated with increasing age in the general population starting at about 60 years of age, we are seeing a similar trend by the time individuals with Down syndrome are in their 20’s.  Some of our data are also beginning to show that individuals with Down syndrome who have more hearing loss have more vestibular deficits and balance difficulties than those with less hearing loss.

Our ears not only help us to hear in quiet, but also work together and with our brains to help us hear in noisy environments. From my graduate work, we learned that people with Down syndrome had a more difficult time hearing in noise than people without Down syndrome. This was the first study done to specifically evaluate that ability and we are now systematically evaluating this in community-based samples of individuals with Down syndrome. An important goal of this work is to identify factors that might contribute to successful listening in background noise.

Teamwork Makes the Dream Work!

Guided by a community advisory board composed of stakeholders in the Down syndrome community, we have a strong group of passionate scientists and staff working on Project INCLUDE at Boys Town National Research Hospital and the University of North Carolina at Chapel Hill.   Most recently our collaborations have grown to include experts at the Linda Crnic Institute for Down Syndrome and Creighton University who will help us begin to understand the physiology behind why individuals with Down syndrome are potentially predisposed to auditory and vestibular difficulties – an important step in reducing the struggles with hearing and balance experienced by people with Down syndrome.

It takes a team to improve hearing and balance healthcare and outcomes for individuals with Down syndrome and their families and we are grateful for those who have already joined the Project INCLUDE community. There are ongoing opportunities for research participation, education, and advocacy. We’d love to hear from you if you or someone that you know is interested in joining our effort!

For More Information:

Please visit our website for more information on Project INCLUDE at Boys Town National Research Hospital: www.boystownhospital.org/research/ProjectINCLUDE.   Consider contacting the author of this article, Dr.  Heather Porter, for questions regarding hearing in individuals with Down syndrome or for further discussion on related topics, including Project INCLUDE. Her email address is Heather.Porter@boystown.org.   ~

H&V Communicator – Winter 2024/25