Weighted blankets are a popular Christmas present this year and have also been described by Time Magazine as one of the best inventions of 2018 (Source: Choice Magazine.) Gravity weighted blankets have sold over $18 US million dollars worth of weighted blankets yet many experts say that there is no evidence that they work.
I must admit I am getting a little tired of ‘experts’ being interviewed who state that there is no evidence for weighted blankets. I wonder if they do a recent google search or if they are going on something that they read years ago when the research trials were just beginning.
It would be more accurate to describe that there is strong evidence in some areas and limited evidence in other areas. In research groups, strong and limited evidence is described according to levels of evidence. This table describes the categories of levels of evidence.
Level of evidence description (Winona State University Evidence Based Practice Tool kit)
Level I
Evidence from a systematic review or meta-analysis of all relevant RCTs (randomized controlled trial) or evidence-based clinical practice guidelines based on systematic reviews of RCTs or three or more RCTs of good quality that have similar results.
Level II
Evidence obtained from at least one well-designed RCT (e.g. large multi-site RCT).
Level III
Evidence obtained from well-designed controlled trials without randomization (i.e. quasi-experimental
Level IV
Evidence from well-designed case-control or cohort studies
Level V
Evidence from systematic reviews of descriptive and qualitative studies (meta-synthesis).
Level VI
Evidence from a single descriptive or qualitative study
Level VII
Evidence from the opinion of authorities and/or reports of expert committees.
As each research paper is published, the evidence is accumulating that weighted blankets work. In 2020 alone, a quick google scholar search will bring 15 articles up on weighted blankets. This includes a systemic review and randomised control trials. As soon as one systemic review is published it is out of date. For example the 2020 article on systemic review found that there were no randomised control studies for insomnia, but since their search was in 2018, there have been multiple randomised control studies published in this area. It is pretty hard to keep up.
In this blog, I will only refer to Level 1 and Level 2 evidence as this is considered the highest levels of evidence. There are hundreds of research papers for Level 3, 4, 5, 6, 7 levels of evidence.
Level 1: Evidence that a weighted blanket decreases anxiety
A systematic review was conducted on weighted blankets and concluded that ‘ the literature supports the use of weighted blankets for anxiety reduction’
(This article also looked at insomnia however there were less articles available at the time of the review and the ones that I have included here are more recent)
“Credible research suggests that weighted blankets may be an appropriate therapeutic tool. The intervention was reviewed for use in relieving anxiety and it was found to demonstrate some success in reducing anxiety. “
Level 2 Evidence in Insomnia, Adult patients receiving chemotherapy, Adult patients with eating disorders in inpatient setting.
Another systematic review on insomnia is warranted given the recent studies in the last 2 years. This includes:
A randomized controlled study of weighted chain blankets for insomnia in psychiatric disorders
Conclusion:
Weighted chain blankets are an effective and safe intervention for insomnia in patients with major depressive disorder, bipolar disorder, generalized anxiety disorder, or attention deficit hyperactivity disorder, also improving daytime symptoms and levels of activity.
Worth The Weight: Weighted Blanket Improves Sleep And Increases Relaxation. (randomised control trial)
Results:
Objective sleep data from the 28 participants who completed all study requirements showed 7% improvement of Wake After Sleep Onset, 2% decrease in Light Sleep, and slight improvement in Sleep Efficiency (1.5%) and Sleep Maintenance (1.4%) during intervention (all ps < 0.05). Additionally, participants felt they fell asleep faster (13% faster), experienced better sleep quality (14% better), felt more rested in the morning (17% more rested), and felt they slept better through the night without waking up (36% improvement). They also reported feeling 13% less stressed at bedtime and 17% more relaxed while trying to fall asleep.
Conclusion
Using a weighted blanket reduces self-reported feelings of stress, enhances feelings of relaxation, and can improve sleep and reduce time awake at night in people with sleep onset and sleep maintenance issues.
Weighted Blankets: Anxiety Reduction in Adult Patients receiving chemotherapy.
Conclusion: “
This randomised control trial concluded that a standard-weight, medical-grade therapeutic weighted blanket can be safely used to reduce anxiety in patients of various weights, and a visual analog scale can be a reliable indicator of patients' state anxiety.
An RCT that assesses the efficacy of weighted blankets on anxiety for patients with severe anorexia nervosa (AN) and avoidant restrictive food intake disorder (ARFID) in an inpatient medical setting. The results demonstrate clinical significance, advancing the field of OT as it supports the use of a sensory intervention to positively impact psychological and emotional states of a patient population with limited evidence to support best practices.
Low levels but not no evidence that weighted blankets improve sleep in Autistic children.
There has been some research on using weighted blankets with autistic children that have not found strong levels of evidence of the benefits. However, the weighted blanket was favored by children and parents, and blankets were well tolerated over this period in this study. There has also been some research with small number that have shown positive benefits, but these need to be larger scale and randomised to add to the evidence base .
In my opinion, this is a tricky area to research due to the sensory over and under responsivity of Autistic People. For example, one child may really dislike deep pressure (and therefore weighted blankets) whilst another child may find it very calming. Ideally, the sensory preferences of autistic children would be identified as part of the protocol for future research.
The practice guideline: treatment for insomnia and disrupted sleep behaviour in children and adolescents with autism spectrum disorder stated that: Clinicians should counsel that there is currently no evidence to support the routine use of weighted blankets or specialized mattress technology for improving disrupted sleep. If asked about weighted blankets, clinicians should counsel that the trial reported no serious adverse events with blanket use and that blankets could be a reasonable nonpharmacological approach for some individuals.
Special Mention:
One researcher stands out as having published multiple papers on Weighted Blankets and championing the benefits – Tina Champagne. We can thank Tina for all of her groundbreaking work that has contributed to weighted blankets being recognised as evidence based and in such popular use that it is now considered a great Christmas present. This is one of Tina Champagnes articles:
Mullen and Champagne et al (2008) explored the effectiveness of a thirty pound weighted blanket on thirty-two adults. Vital sign metrics showed that using the weighted blanket in a lying down position was safe. Thirty-three percent of participants experienced a lowering of electro-thermal activity, sixty-three percent reported lower anxiety and seventy eight percent preferred the weighted blanket as a calming modality.
Safety
For people with disabilities and medical conditions it is recommended to discuss the option of a weighted blanket with an Occupational Therapist and your treating Doctor. This blog is a general description of the benefits and is not advice specific to the individual.
Further Information
Weighted Blankets are a Sensory Modulation intervention using deep pressure stimulation.
Further information on Sensory Modulation is available from:
O Sullivan, J & Fitzgibbon, C (2018) Sensory Modulation Resource Manual
Champagne, T. (2011) Sensory Modulation & Environment: Essential elements of occupation
Using Sensory Modulation Online Course 5 hours CPD.
References
Rachel Ohene, MOT, OTR/L; Christina Logan, MS, OTR/L; Ashlie Watters, PhD; Figaro Loresto, PhD, RN; Kathryn Eron; Philip Mehler, MD, FACP, FAED (2020) Assessing the Impact of Weighted Blankets on Anxiety for Patients With Eating Disorders in an Inpatient Setting: A Randomized Control Trial Pilot
A randomized controlled study of weighted chain blankets for insomnia in psychiatric disorders
Ekholm B, Spulber S, Adler M. (2020) A randomized controlled study of weighted chain blankets for insomnia in psychiatric disorders. J Clin Sleep Med. 2020;16(9):1567–
Danoff-Burg, Sharon & Rus, Holly M & Martir, L & Raymann, Roy. (2020). 1203 Worth The Weight: Weighted Blanket Improves Sleep And Increases Relaxation. Sleep. 43. A460-A460. 10.1093/sleep/zsaa056.1197
Eron, K, Kohnert, L, Watters, A, Logan, C, WEisner-Rose, M, Mehler, P. (2020) Weighted Blanket Use: A systematic Review American Journal of Occupational Therapy, August 2020, Vol. 74, 7411515404. https://doi.org/10.5014/ajot.2020.74S1-PO5511
P Gringras, D Green, BWright, C Rush, M Sparrowhawk, K Pratt, V Allgar, Naomi Hooke, D Moore, Z Zaiwalla and L Wiggs (2014) Weighted Blankets and Sleep in Autistic Children—A Randomized Controlled Pediatrics August 2014, 134 (2) 298-306; DOI: https://doi.org/10.1542/peds.2013-4285
Choice article: https://www.choice.com.au/health-and-body/conditions/trouble-sleeping/articles/do-weighted-blankets-work
Mullen, B., Champagne, T. Krishnamurty, S. Dickson, D & Gao, R. (2008) Exploring the safety and therapeutic effects of deep pressure stimulation using a weighted blanket. Occupational Therapy in Mental Health, 24, 65 -89
Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology
Ashura Williams Buckley, Deborah Hirtz, Maryam Oskoui, Melissa J. Armstrong, Anshu Batra, Carolyn Bridgemohan, Daniel Coury, Geraldine Dawson, Diane Donley, Robert L. Findling, Thomas Gaughan, David Gloss, Gary Gronseth, Riley Kessler, Shannon Merillat, David Michelson, Judith Owens, Tamara Pringsheim, Linmarie Sikich, Aubyn Stahmer, Audrey Thurm, Roberto Tuchman, Zachary Warren, Amy Wetherby, Max Wiznitzer, Stephen Ashwal First published February 12, 2020, DOI: https://doi.org/10.1212/WNL.0000000000009033
Winona State University Evidence Based Practice Tool kit: https://libguides.winona.edu/c.php?g=11614&p=61584
: This level of effectiveness rating scheme is based on the following: Ackley, B. J., Swan, B. A., Ladwig, G., & Tucker, S. (2008). Evidence-based nursing care guidelines: Medical-surgical interventions. (p. 7). St. Louis, MO: Mosby Elsevier.
https://pediatrics.aappublications.org/content/134/2/298.short