Highlights
- •A 15-lb weighted blanket reduced aspects of chronic pain more than a 5-lb weighted blanket.
- •The heavier weighted blanket was more pain relieving for highly anxious individuals.
- •Weighted blanket-related pain reductions were not mediated by changes in state anxiety or sleep.
- •Interoceptive or social-affective effects of deep pressure may mediate pain relief.
- •A 15-lb weighted blanket may be an accessible, low-cost tool to reduce aspects of chronic pain.
Abstract
Pleasant sensation is an underexplored avenue for modulation of chronic pain. Deeper
pressure is perceived as pleasant and calming, and can improve sleep. Although pressure
can reduce acute pain, its effect on chronic pain is poorly characterized. The current
remote, double-blind, randomized controlled trial tested the hypothesis that wearing
a heavy weighted blanket – providing widespread pressure to the body – relative to
a light weighted blanket would reduce ratings of chronic pain, mediated by improvements
in anxiety and sleep. Ninety-four adults with chronic pain were randomized to wear
a 15-lb. (heavy) or 5-lb. (light) weighted blanket during a brief trial and overnight
for one week. Measures of anxiety and chronic pain were collected pre- and post-intervention,
and ratings of pain intensity, anxiety, and sleep were collected daily. After controlling
for expectations and trait anxiety, the heavy weighted blanket produced significantly
greater reductions in broad perceptions of chronic pain than the light weighted blanket
(Cohen's f = .19, CI [-1.97, -.91]). This effect was stronger in individuals with high trait anxiety (P = .02). However, weighted blankets did not alter pain intensity ratings. Pain reductions
were not mediated by anxiety or sleep. Given that the heavy weighted blanket was associated
with greater modulation of affective versus sensory aspects of chronic pain, we propose
that the observed reductions are due to interoceptive and social/affective effects
of deeper pressure. Overall, we demonstrate that widespread pressure from a weighted
blanket can reduce the severity of chronic pain, offering an accessible, home-based
tool for chronic pain.
The study purpose, targeted condition, study design, and primary and secondary outcomes
were pre-registered in ClinicalTrials.gov (NCT04447885: “Weighted Blankets and Chronic
Pain”).
Perspective
This randomized-controlled trial showed that a 15-lb weighted blanket produced significantly
greater reductions in broad perceptions of chronic pain relative to a 5-lb weighted
blanket, particularly in highly anxious individuals. These findings are relevant to
patients and providers seeking home-based, nondrug therapies for chronic pain relief.
Key words
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Article info
Publication history
Published online: August 20, 2021
Accepted:
July 22,
2021
Received in revised form:
July 8,
2021
Received:
April 21,
2021
Footnotes
This work was supported by UC San Diego Health and the National Center for Complementary and Integrative Health – National Institutes of Health (R00-AT009466, F32- AT010843).
The authors have no conflicts of interest to disclose.
Identification
Copyright
© 2021 by United States Association for the Study of Pain, Inc.
