Kate Dougherty associates all of her son Eliot’s doctor’s appointments with a treat, such as a trip to his favorite lunch spot or a professional show of bull riding – one of Elliot’s favorite sports, second only to baseball and basketball. So when they flew from Missouri to Boston in 2018 for Eliot to have a new device implanted in his chest to treat his sleep apnea, the treat must have been huge. Three days after the operation, Elliot was in his first Red Sox game.
Since then, “it’s been a miracle”, says his mother.
Elliot, 13, with Down syndrome, has suffered from obstructive sleep apnea all his life. The problem – which arises when someone cannot get enough oxygen while sleeping – affected about 80% of people with Down syndrome and can lead to brain fog, ADHD-like symptoms, and a host of other issues. The problems can often be seen as “oh, it’s just Down syndrome,” Dougherty said. “But there’s no ‘it’s just Down syndrome’.”
Elliot received the implant as part of a Phase 1 clinical study trialwhose results were published Thursday in JAMA Otolaryngology – Head & Neck Surgery.
For children with sleep apnea, the first line of treatment is to remove the tonsils and adenoids. Elliot did this at age four and his mum said it worked for a short time. But sleep apnea has returned with a vengeance, as it does for many children with Down syndrome who tend to have larger tongues and weaker muscle tone. The next treatment option is a CPAP machine, which uses a face mask to keep a person’s air pressure stable while they sleep. But children with Down syndrome also have sensory issues or feel restless, and many are unable to wear the mask for these or other reasons.
Options are limited after that. Some people have surgery to reduce the size of their tongue and create space in the airways, but Dougherty didn’t want to do it for Eliot.
At a Down syndrome conference, she heard about a new study to test a device called a hypoglossal nerve stimulator. It’s like a pacemaker, implanted in the chest with a direct line to the tongue. The device – turned on in the evening using a remote control – stimulates a nerve to move the tongue throughout the night, opening up the patient’s airways.
The technology, developed by Minneapolis-based company Inspire, won FDA approval in 2020 for adults with sleep apnea. When pediatric otolaryngologist Christopher Hartnick saw the device’s first study in adults, he realized it could potentially help children with Down syndrome.
“I went to the Inspire people and became this pesky pediatrician who called many, many times saying I had this population in need,” said Hartnick, who practices at Massachusetts General Hospital.
In 2015, Hartnick and doctors at four other institutions across the country began a clinical trial to test the device in 42 children with Down syndrome and severe sleep apnea, including Elliot.
As this was a phase 1 study, the main objective was to ensure that the implant was safe. Of 42 children, there were few complications – the most common side effect was tongue or mouth discomfort, which occurred in five children. But early results on efficacy were also encouraging. Researchers tracked the apnea-hypopnea index, or the number of times per hour a person does not get enough oxygen while sleeping. On average, the device allowed patients to have about 50% fewer of these events per hour. For three-quarters of the patients, the number of events fell below the threshold for severe sleep apnea, which is 10 or more episodes per night.
For Dougherty, the change in Eliot’s quality of life was clear. Elliot, who had the procedure when he was 10, can stay up late at sleepovers and skip daytime naps when he previously couldn’t. He is no longer in trouble at school like before, can concentrate better and has seen his speech skills improve.
“Once we got sleep apnea under control, all the other pieces started falling together,” Dougherty said. “I just can’t imagine how much better life would have been for Elliot if we could have done this sooner.”
Kishore Vellody, director of the Down Syndrome Center at UPMC Children’s Hospital in Pittsburgh, said that while the study only included a small number of patients, he finds the research promising.
“Hopefully as they add numbers, we start to see more of an effect that holds even in larger populations,” said Vellody, who was not involved in the research.
The researchers plan further studies on the device, particularly on its potential to improve speech for a patient with Down syndrome. The teams found that many patients like Elliot developed improved speech skills after implantation, possibly due to increased use of their tongue at night.
For the device to be used more widely in children with Down syndrome, it would need to gain FDA approval.
Tim Herbert, CEO of Inspire, said the company was working directly with the FDA to determine which approval path would work best. The company is interested in broad pediatric approval, but hasn’t said whether it plans to first seek approval just for children with Down syndrome. Hartnick said that if the company is aiming for approval for a broader and possibly more cost-effective general pediatric population, rather than just for children with Down syndrome, it will require more research — and therefore more time for families to wait.
“It may seem like a small market to you, but it’s a pretty big market and it’s representative, and if we have to walk before we run, that’s really the dialogue we’re in,” he said.
The Dougherty family is grateful for the change the device has made in Elliot’s life. He turns it on by himself every night and turns it off in the morning. When asked what he remembered about getting the implant in Boston, Elliot replied, “It was awesome.”