By Marshal D. Haneisen
A team of Massachusetts medical professionals is leading the way in creating an innovative screening approach that would identify Obstructive Sleep Apnea (OSA) in people with Down syndrome.
OSA occurs when a person's airway is restricted or blocked by a physical feature during sleep. Individuals with OSA may stop and resume breathing during sleep, and the resulting reduced oxygen supply can cause significant medical problems. OSA occurs more frequently in children and adults with Down syndrome than in neurotypical peers.
"Because of differences in their craniofacial features, people with Down syndrome are more prone to obstructive sleep apnea," said Dr. Brian Skotko, MD, MPP, and co-director of the Massachusetts General Hospital Down Syndrome Program in Boston. He is leading the team studying OSA and Down syndrome.
Data indicates that OSA occurs in 55% to 97% of the population of individuals with Down syndrome, compared to 1%-4% of the neurotypical pediatric population. Because of the physical and cognitive challenges of a person with Down syndrome, the effects of OSA can be more damaging.
"In addition to exacerbating medical conditions like hyper-tension, untreated apnea can lead to short- and long-term loss of cognitive abilities. As I explain to my patients' parents, their sons and daughters with Down syndrome work so hard in school, I would hate for apnea to undo some of their well-earned cognitive gains," Dr. Skotko said.
Parents may assume OSA would present clues via symptoms such as snoring, restlessness, or frequent waking in the night. Consequently, they may be tempted to wait until a child displays signs of OSA. However, Skotko explained that sleep apnea is often silent, with no warning symptoms. The American Academy of Pediatrics currently recommends that all children with Down syndrome undergo a sleep study, also known as a polysomnogram, by age 4, and annually thereafter if findings indicate OSA.
Yet, many parents resist coordinating a sleep study for a variety of reasons:
* A presumption that the child will not cooperate and study results may be inconclusive. * The child might be rigid about a bedtime routine. * The child may be anxious about sleeping away from home. * The child might find the monitoring equipment unsettling.
Laura Hardiman of Haverill is mother to a 21-year-old son with a dual diagnosis of Down syndrome and autism. He has been a restless sleeper since early childhood.
"Alex is nonverbal, and when his brain switches on, he is up and about," she said. As a toddler, he began climbing out of his crib at night. Like many parents, Hardiman adopted the practice of using a child safety gate to ensure that her son would not leave his bedroom and wander through the house during the night. That child safety gate became an important part of his bedtime routine.
Now, at 21, he wants the gate in place at bedtime. He has never tried to climb it, but identifies it as part of his bedtime environment, she said. This is one example of how a child may have a bedtime routine that is difficult to replicate in a hospital setting for a sleep study. Alex has sensory issues, which she believes contributes to his restless sleeping. Around age 16, he began piling pillows around himself when he went to sleep.
"As he got older and heavier, I think he was propping them up to open his airway," Hardiman said. "He often sleeps sitting up, sometimes he sleeps on his side or on his back. But if he is on his back, he will snore."
Hardiman suspects her son has OSA. But after two attempts at a sleep study, she is no closer to an answer on that question. The first attempted sleep study was held at Boston Children's Hospital when Alex was around 10. His adenoids and tonsils had previously been removed, but he was still restless at night. Hardiman was hoping to learn if apnea was contributing to this restlessness. But he is a very light sleeper, and the gel pads, wires, and even the oxygen monitor on his fingertip all prevented him from sleeping, she said.
They attempted a sleep study for a second time this summer at Massachusetts General Hospital. Again, the study could not collect enough data for an accurate assessment.
"He is bigger and stronger and more aware of his anxiety," she said. "As soon as he woke up and got out of bed, he was done."
Geography is another reason parents delay on coordinating sleep studies. Sleep studies can usually be scheduled through Down syndrome clinics, where children and adults with Down syndrome receive comprehensive medical care by a variety of specialists and experts. However, Skotko stated that only about 5% of all people with Down syndrome are followed by a Down syndrome clinic. Geography is sometimes a factor. The three Down syndrome clinics in Massachusetts are located at Massachusetts General Hospital, Children's Hospital Boston, and UMass Medical Center in Worcester. However, according to the website for the Global Down Syndrome Foundation, only 33 states in the country have at least one clinic. Even when a state has a clinic, it can mean families drive hours to a medical facility for the study.
Cost and complications in obtaining insurance coverage are other factors influencing the scheduling of sleep studies. According to Dr. Skotko, out-of-pocket costs to a family for a sleep study can be $3,000 or more. Insurance companies or Medicaid coverage may require prior authorization, which can involve a lot of paperwork.
Dr. Skotko's team combined a range of assessment tools -- including questionnaires for parents about their children's sleep, evaluation of vital signs, blood data, and urine tests, three-dimensional digital photography of craniofacial features, lateral cephalograms, physical examination, dental examination, and measurement of metabolic markers -- to determine which tests were most helpful in diagnosing or ruling out the presence of OSA.
The team has completed the first round of research; the second round is in process. If the validation round of testing is successful, it may result in a tool primary care physicians will be able to use to conduct a preliminary screening to determine if a sleep study should be scheduled. The vision is to create a webpage primary care physicians can use to enter the variable data. An algorithm would then predict the likelihood of OSA. Patients with Down syndrome who have negative results on the assessment probably could avoid a sleep study, Dr. Skotko said.
In the meantime, he encourages families to follow the American Academy of Pediatrics recommenda-tions for sleep studies to identify OSA.