A new study shows that weighted blankets are a safe and effective intervention in the treatment of insomnia.
Swedish researchers have found that insomnia patients with psychiatric disorders experienced reduced insomnia severity, improved sleep, and less daytime sleepiness when sleeping with a weighted chain blanket.
The study appeared on September 15 in the Journal of Clinical Sleep Medicine.
Four weeks of weighted blankets reduce insomnia by 50%
Results of the randomized, controlled study show that participants using the weighted blanket for four weeks reported significantly reduced insomnia severity. They also had better sleep maintenance and a higher daytime activity level. Moreover, they experienced reduced symptoms of fatigue, depression and anxiety.
Participants in the weighted blanket group were almost 26 times more likely to experience a decrease of 50% or more in their insomnia severity compared with the control group. They were also nearly 20 times more likely to achieve remission of their insomnia. These positive results remained during a 12-month follow-up phase of the study.
“A suggested explanation for the calming and sleep-promoting effect is the pressure that the chain blanket applies on different points on the body, stimulating the sensation of touch and the sense of muscles and joints, similar to acupressure and massage,” said principle investigator Mats Alder, a consultant psychiatrist in the department of clinical neuroscience at the Karolinska Institutet in Stockholm, Sweden.
“There is evidence suggesting that deep pressure stimulation increases parasympathetic arousal of the autonomic nervous system and at the same time reduces sympathetic arousal, which is considered to be the cause of the calming effect,” Alder said.
The right weight matters
The study involved 120 adults (68% women, 32% men) previously diagnosed with clinical insomnia and a co-occurring psychiatric disorder: major depressive disorder, bipolar disorder, attention deficit hyperactivity disorder, or generalized anxiety disorder. They had a mean age of about 40 years.
The researchers randomly assigned the participants to sleep for four weeks with either a chain-weighted blanket or a normal blanket. Participants assigned to the weighted blanket group tried an 8-kilogram (about 17.6 pounds) chain blanket at the clinic. Ten participants found it to be too heavy and received a 6-kilogram (about 13.2 pounds) blanket instead. Participants in the control group slept with a light plastic chain blanket of 1.5 kilograms (about 3.3 pounds).
Nearly 60% of weighted blanket users had a positive response with a decrease of 50% or more in their ISI score after four weeks. This compared to only 5.4% in the control group. Remission, a score of seven or less on the ISI scale, was 42.2% in the weighted blanket group. In the control group it was only 3.6%.
Most opted for the heaviest weighted blanket
After the initial four-week study, all participants had the option to use the weighted blanket for a 12-month follow-up phase. They tested four different weighted blankets. Two of these were chain blankets (of 6 or 8 kilograms) and two were ball blankets (6.5 or 7 kilograms). After the test, and they were freely allowed to choose the blanket they preferred, with most selecting a heavier blanket. Only one participant discontinued the study due to feelings of anxiety when using the blanket. After 12 months, 92% of weighted blanket users responded to the treatment, and 78% were in remission.
“I was surprised by the large effect size on insomnia by the weighted blanket and pleased by the reduction of levels of both anxiety and depression,” said Adler.
In a related commentary, also published in the September issue of JCSM, Dr. William McCall writes that the study results support the psychoanalytic “holding environment” theory, which states that touch is a basic need that provides calming and comfort.
McCall urges providers to consider the impact of sleeping surfaces and bedding on sleep quality, while calling for additional research into the effect of weighted blankets.
Study: “A randomized controlled study of weighted chain blankets for insomnia in psychiatric disorders“
Authors: Bodil Ekholm, Stefan Spulber, and Mats Adler
Published in: Journal of Clinical Sleep Medicine
Publication date: September 15, 2020
Photo: by Claudio_Scott from Pixabay
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