True or false: If I give you a placebo pill and tell you it will zap your back pain, it’s crucial that I not also tell you the pill is just made of sugar. Deception is a key ingredient for the mind to manufacture a remedy out of nothing, right?
That’s how we thought the placebo effect worked since its discovery some 70 years ago, but new research is offering a different take (or, at least, a modification of what we thought we knew). A study suggests that the placebo effect may not hinge entirely on deception, but rather on the effect of being “immersed in treatment.” In other words, if taking a placebo is part of the treatment, the mind can use it to boost treatment effects even if patients know they aren’t taking actual medicine.
The study was conducted by a team of researchers from Beth Israel Deaconess Medical Center in Boston and Instituto Superior de Psicologia Aplicada (ISPA) in Lisbon, Portugal. Just under 100 patients suffering from chronic lower back pain were given a 15-minute explanation of the placebo effect and then divided into two study groups for three weeks. One group took nonsteroidal anti-inflammatory drugs (NSAIDs, the class of drugs that includes ibuprofen, which most were already taking before the study) and the other group was instructed to also take a placebo pill twice daily. The placebos were clearly labeled “placebo pills” on the bottle.
Both groups were told to stick to their assigned treatments and not take anything else during the study period, or make any major changes in lifestyle or routines that might affect their health. After three weeks the groups were reevaluated to test their pain levels against a baseline level set at the beginning of the study.
The results showed that patients in both groups experienced a reduction in pain. The group taking only NSAIDs experienced a 9% reduction in their usual pain level and a 16% reduction in maximum pain. But the group taking NSAIDs plus a placebo experienced a 30% reduction in both usual and maximum pain. The placebo boost was more than three times as much for usual pain and nearly twice as much for maximum pain.
That’s a significant result, and more than a little odd considering that everyone in the placebo group knew they were popping fake pills.
"Our findings demonstrate the placebo effect can be elicited without deception. Patients were interested in what would happen and enjoyed this novel approach to their pain. They felt empowered," said lead study author Claudia Carvalho, Ph.D., ISPA.
The results are in line with those of a previous study conducted by the Beth Israel team, led by Professor Ted Kaptchuk from Harvard, showing that patients suffering from irritable bowel syndrome (IBS) can experience improvement from knowingly taking a placebo. About 60% of patients reported less severe IBS symptoms after taking a placebo pill.
These are interesting outcomes, but it’s possible the non-deception element was overstated. Both the latest study and the IBS study were pitched to participants as “novel mind-body management" studies, which the researchers admit may have attracted people already given to thinking that “mind-body” interventions work just as well as traditional medicine. If that’s the case, then deception wasn’t really removed from the equation. The expectation of a result was still created for the participants (i.e. the placebo would help them) just not via traditional means. A true non-deceptive test of placebos should remove all such suggestion-planting.
Bottom line: the study results could be skewed by giving placebos to people predisposed to thinking they'll work. Quoting the researchers from the study limitations section, "The results might not be generalizable to all patients."
Having said that, there’s at least enough in these studies worth following up in larger ones to probe why placebos work well for certain people, which could help determine if we’re missing opportunities to use them therapeutically. Pain management can use all the help we can give it.
The latest study was published in the journal Pain.
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