The Value of Placebos

Tuesday, March 09, 2010

Via Amit Ghate is an interesting article about a burgeoning area of research that recent problems experienced by the pharmaceutical industry during drug trials have invigorated: Placebo effects have been growing stronger lately, sinking several candidate drugs and even calling into question the effectiveness of established drugs upon reevaluation.

What might be the basis of the placebo/nocebo effect, and how might we take advantage of it?

Further research by [Fabrizio] Benedetti [of the University of Turin] and others showed that the promise of treatment activates areas of the brain involved in weighing the significance of events and the seriousness of threats. "If a fire alarm goes off and you see smoke, you know something bad is going to happen and you get ready to escape," explains Tor Wager, a neuroscientist at Columbia University. "Expectations about pain and pain relief work in a similar way. Placebo treatments tap into this system and orchestrate the responses in your brain and body accordingly."

[O]ne way that [a] placebo aids recovery is by hacking the mind's ability to predict the future. We are constantly parsing the reactions of those around us--such as the tone a doctor uses to deliver a diagnosis--to generate more-accurate estimations of our fate. One of the most powerful placebogenic triggers is watching someone else experience the benefits of an alleged drug. Researchers call these social aspects of medicine the therapeutic ritual.
This research is, of course, in addition to making obviously-needed improvements in the clinical trials themselves.
Benedetti has helped design a protocol for minimizing volunteers' expectations that he calls "open/hidden." In standard trials, the act of taking a pill or receiving an injection activates the placebo response. In open/hidden trials, drugs and placebos are given to some test subjects in the usual way and to others at random intervals through an IV line controlled by a concealed computer. Drugs that work only when the patient knows they're being administered are placebos themselves.
It is interesting how the concept of "placebo" is evolving over time with added knowledge of how the body and mind work and interact. From first denoting a class of sham or merely palliative remedies, to a presumably ineffective stand-in for a real drug, and now perhaps to more of a type of psychological or psychosomatic effect.

-- CAV

P.S. Statistician Nick Barrowman views the idea of a placebo effect with a much-needed jaundiced eye.


: Corrected a spelling error.
10-5-11: Added PS.


Steve D said...

The article makes a lot of sense and there is nothing in the conclusions seem to violate common sense.

Very interesting that the placebo effect (or response) can vary so much depending upon when and where the study is performed. If the effect is getting stronger over time, perhaps it is because we expect more from our drugs. Still only a long term study could actually prove it was getting strong over time.

Also, interesting is that when you take a drug you may end up with the physical effect of the drug PLUS the placebo effect, giving it effectively more power?

I wonder what the limits of this are. Another question is how can we best harness this response for improved health?

I worked for a pharmaceutical company for a short period of time. All the drugs are developed to hit specific (usually enzyme) targets and they have real physiological effects which can be measured. The fact that naloxone can block one placebo response suggests that it has real and therefore potentially identifiable targets. Perhaps we can identify the targets for other placebo responses and use them to develop new drugs with effects stronger than the placebo.

Gus Van Horn said...

"[P]erhaps it is because we expect more from our drugs. Still only a long term study could actually prove it was getting strong over time."

I think this is precisely because of the success of Western medicine.

Imagine how much stronger the placebo effect can be when actual evidence becomes part of the therapeutic ritual, independently of whether the evidence actually supports what the patient is being told in particular.

It's as if the successes of scientific medicine have rubbed off onto the effectiveness of suggestion.