Patients with chronic pain conditions such as fibromyalgia experience similar pain relief with a placebo as people without chronic pain, a new study indicates.
Harnessing the so-called placebo effect, researchers suggest, could be a viable strategy for treating fibromyalgia and other disorders, and for reducing dependence on pain medications.
The study, “Individuals with chronic pain have the same response to placebo analgesia as healthy controls in terms of magnitude and reproducibility,” was published in the journal PAIN.
The placebo effect is a phenomenon in which a treatment that is demonstrably not effective results in therapeutic benefits. Yet, what causes such effects remains unclear.
Placebo effects most often are discussed in the context of clinical trials and other scientific evaluations; to demonstrate efficacy, a potential therapy must be superior to an inactive placebo.
Conditions such as fibromyalgia and osteoarthritis are characterized by chronic pain. Since pain affects everyone differently, it might be particularly amenable to being influenced by the placebo effect.
“Pain normally increases negative emotions, which in turn increases the subjective experience of pain … That is why chronic pain patients have psychological co-morbidities such as anxiety, depression, pain catastrophizing [the inability to stop thinking about pain and its amplification] and cognitive impairments. For this reason, the role of expectancy and anxiety in modulation of pain by placebo has a role in treating these patients,” Andrea Power, a researcher at The University of Manchester, England, and the study’s first author, said in a press release.
Yet, the utility of the placebo effect in such cases relies on the assumption that people with chronic pain experience the placebo effect in a manner comparable to healthy individuals.
To test this hypothesis, the team from the U.K. recruited 79 participants with fibromyalgia, 60 with osteoarthritis, and 98 without chronic pain. All participants had an inert cream — that is, a cream with no known pain-relieving ingredients — applied to their forearm. Then, a laser was used to cause controlled pain, and the participants were asked to rate their pain, expectation of pain relief, and anxiety.
They were divided into two groups. The “placebo” group was told that the cream may or may not be a local anesthetic (pain-relieving) cream. The “control” group was told that the cream was inert. In this way, the researchers accounted for participants’ expectations.
Regardless of underlying diagnosis — fibromyalgia, osteoarthritis, or neither — participants in the placebo group had significantly lower pain scores than the controls. No differences were seen in the magnitude of effects and in the expectancy of pain relief across the different diagnoses in the placebo group.
Results were similar two weeks later, indicating that the benefits are consistent.
“The results demonstrate that individuals with chronic pain respond to experimental placebo analgesia in a similar and reproducible manner as healthy individuals, despite higher levels of psychological co-morbidity,” the researchers wrote.
These findings support using the placebo effect as a beneficial strategy against chronic pain. “What was previously considered to be a nuisance variable has now been shown to have substantial potential to improve patient outcomes in chronic pain,” said Manoj Sivan, MD, study co-author and professor at the University of Leeds.
Notably, placebo is typically safe, According to the team, it could be used as a replacement for other treatments, such as opioids, which can cause more severe side effects.
“Anything which can reduce the use of Opioids and the concomitant side effects has to be welcomed. Placebo has been shown to work for many individuals without any harmful side effects. Therefore I believe that it could be used more widely in the treatment of chronic widespread pain,” said Val Derbyshire, who has fibromyalgia and osteoarthritis, and collaborates with the Salford Fibromyalgia Support Group.