according to Stephen H. Sheldon, DO.
“They wake up frequently,” Dr. Sheldon, professor of pediatrics and neurology at Northwestern University, Chicago, said during the Revolutionizing Atopic Dermatitis symposium. “They may not stay up for long periods of time, but they move about often. There’s a loss of about 50 minutes of sleep per night in children with AD. This loss can result in significant sleep debt the following day. They have difficulty settling at night. Once they get into bed, they have difficulty falling asleep, and many of them have difficulty staying asleep.”
Dr. Stephen H. Sheldon
At the sleep medicine center at Lurie Children’s Hospital of Chicago, he and his colleagues have observed that some children with AD complain of difficulty with limb movements. “Part of the issue has been that they have been diagnosed with different sleep-related disorders, such as period limb movement disorder, restless leg syndrome, and growing pain,” Dr. Sheldon said. “Often, they do not know how to describe the manifestations of their leg discomfort in restless leg syndrome and period limb movement disorder and limb movements of sleep.”
Children who complain of growing pains say that their legs hurt, he continued. Sometimes they’ll say that they feel like spiders are crawling on their legs, or that their legs itch, but they often say they have pain in their legs that wakes them up and keeps them from keeping their legs still.
According to the American Academy of Sleep Medicine, periodic limb movement disorder of sleep is characterized by frequent limb movements that last at least 0.5 seconds and are separated by no more than 90 seconds. “They’re four movements in a row that are at least 5 seconds apart,” Dr. Sheldon said.
Interestingly, he added, children who have limb movement disorder have symptoms during the day, similar to adults. “But we see many children with periodic limb movements of sleep whose arms and legs are moving all night, and they don’t have many symptoms during the day.” These children may have difficulty falling or staying asleep, but do not fulfill all of the American Academy of Sleep Medicine criteria for diagnosis of periodic limb movement disorder, he added.
In 2018, Lourdes M. DelRosso, MD, EdD, of Seattle Children’s Hospital, and colleagues described a new sleep problem they termed restless sleep disorder: those who do not fit the criteria for any other sleep disorder but have daytime impairment.
“On video they have very frequent movements – more than five movements an hour of major body activity,” Dr. Sheldon explained. “They’ll move their trunk, their legs, and reposition themselves. We have found that there are many children who presented to the sleep disorder center with restless sleep, limb movement disorder, periodic limb movements of sleep, and daytime symptoms that would fulfill the criteria of periodic limb movement disorder but also have atopic dermatitis.”
Recently, Dr. Sheldon and his colleagues used polysomnographic variables to study children who presented to Lurie Children’s Hospital with AD and symptoms such as difficulty maintaining sleep and snoring with allergic rhinitis. They found that there were increased periods of being awake after the onset of sleep, “meaning the children fell asleep fairly easily in the beginning of the night but they had significant wake after they fell asleep,” he said. “They would wake up in the middle of the night and stay awake for long periods of time – either one long session or multiple shorter sessions throughout the night. They had increased total limb movements per hour of sleep. This means that their limb movements were greater than five events per hour of sleep and it resulted in restless sleep and limb movements that would fulfill the criteria of periodic limb movement disorder.”
Most of these children had mild to moderate AD, he continued. “We feel that the sensory afferent loop in these youngsters doesn’t really turn off completely when they’re asleep. This is ripe for further study, but it makes intuitive sense that if the sensory afferent loop continues during sleep, it may affect the arousal system significantly.”
Dr. Sheldon recommended that any child who presents with a diagnosis of periodic limb movement disorder, periodic limb movements of sleep, or restless sleep disorder should be evaluated for AD. “The treatment then, would first require differentiation between periodic limb movement disorder of sleep and AD. Both should be addressed at the same time in order to solve the child’s daytime AD problem as well as the sleep-related issues that occur with an AD diagnosis.”
He reported having no financial disclosures.