A study by University of Houston sleep expert and psychology professor Candice Alfano has found that weighted blankets, between 5 and 10 pounds, do not improve sleep for children who have experienced various types of maltreatment including abuse or neglect.
The popularity of weighted blankets has soared in recent years, largely based on the idea that the pressure of a heavy blanket induces feelings of relaxation and calm that help us fall asleep. Yet surprisingly little research has examined claims of improved sleep, particularly among children.
In fact, whether weighted blankets might improve sleep among children who spend time in foster care – a population that experiences high rates of sleep problems - had never been examined.
Until now.
The study by Alfano and her team, and published in Journal of Clinical Sleep Medicine, included 30 children, aged 6-to-15 years old, adopted from foster care in Texas. The group was asked to use a weighted blanket for two weeks and their usual blanket for two weeks at home in random order. Sleep was monitored continuously for one month using both sleep diaries and actigraphs. An actigraph is a wristwatch-like device that reliably tracks sleep-wake patterns.
"We were somewhat surprised to find no differences in either objective or subjective sleep variables based on blanket type, including total sleep time, sleep onset latency, wake minutes after sleep onset, or sleep quality ratings. We also explored whether child age, sex, or maltreatment/trauma history might have influenced outcomes, but no such effects were found," said Alfano, who is also director of the Sleep and Anxiety Center of Houston at UH.
Alfano's research has routinely found that, even after adoption, a large proportion of children who spend time in foster care have persistent sleep problems, including difficulty falling asleep, nighttime awakenings, nightmares and/or parasomnias.
"We have heard from at least some foster and adoptive parents that a weighted blanket has seemed to help their child sleep better, so we wondered" Alfano said. "Childhood maltreatment can produce sleep problems via multiple pathways, including hyperarousal of the body's stress response systems and/or feelings of increased fear and insecurity at night. Theoretically, use of the weighted blanket might reduce these symptoms and improve sleep."
Unfortunately, that is not what the research found.
Alfano emphasizes, however, that their study is not the final word. "Children who have histories of maltreatment are a very diverse group, so more well-controlled studies using larger samples of children are still needed," said Alfano.
The study was co-authored by doctoral students Anthony B. Cifre and Alyssa Vieira.
