Sleep experts define pediatric sleep condition, iron deficiency likely culprit

“For years, we would see children whose parents were concerned that there was something wrong because they moved a lot in their sleep but the diagnosis and tools we had available were not able to identify any abnormalities. We would tell those families that there was nothing wrong. Parents would insist,” ​explained Dr. Lourdes DelRosso, Seattle Children’s pediatric sleep specialist. “Finally, I contacted an expert in movement disorders and together, we designed the research to be able to see and assess the movements at night.” ​

Along with an international panel of sleep experts, DelRosso led the charge in defining a new pediatric sleep disorder they call restless sleep disorder, or RSD. 

The description and medical definition of RSD is detailed in a paper published in Sleep Medicine, offering a new tool to help more children challenged by restless sleep.

To get there, the panel of ten sleep experts agreed on 16 consensus questions to guide the development of diagnostic criteria. The questions addressed things such as evidence, frequency and duration criteria for RSD, the age of RSD sufferers, and areas for future research. 

The authors agreed that RSD occurs in children 6-18 years old and can lead to attention impairment, mood and behavioral problems and other issues at home and school due to poor sleep quality.

DelRosso said parents often characterize their children's behavior as wrestling in their sleep or thrashing in the bed. 

Iron

Thankfully, parents may be able to solve their children’s sleep problems by simply supplementing them with iron.

DelRosso explained that iron is a cofactor of dopamine synthesis in the brain and it’s hypothesized that iron helps with dopamine and dopamine in turn helps with the movements providing a more restful sleep.

“There’s a lot of evidence that points toward an association between movement disorders and iron deficiency in the brain,”​ said DelRosso. “In children with RSD, we recommend checking their levels of a protein needed to store iron called ferritin and if they are low, begin supplementing with iron.”​

For their study, DelRosso said they measured the ferritin levels of their subjects, which is a marker of iron stores in the rests of the body. 

According to their findings, the ferritin levels came about to be between 14-20. 

“Although within normal, they were in the low range of normal. At these levels, some studies have shown that there is already non-anemic iron deficiency,"​ she explained. 

Sleep and immune health 

DelRosso said she can’t emphasize enough the importance of sleep in everyone, especially in the growing and developing brain of a child. 

“We see in studies on sleep deprivation how lack of sleep adversely affects the immune system. There is a study on the flu vaccine that shows that people who were sleep deprived the week prior to receiving the vaccine did not develop as good an antibody level as those with good sleep,"​ said DelRosso. "Also, lack of sleep weakens our immune system and makes us more vulnerable to infections.” ​

Source: Sleep Medicine​

2020 Nov;75:335-340. doi: 10.1016/j.sleep.2020.08.011​

“Consensus diagnostic criteria for a newly defined pediatric sleep disorder: restless sleep disorder (RSD)”​

Authors: L. DelRosso et al.