Everyone knows of the placebo effect, where a person feels better after being given something that should have no effect because they believe that have been given a medication. A new study has found a monetary placebo effect. A patient's perception of the cost of the treatment appears to affect how well it works. An injection of saline worked on people who thought they had been given an expensive medication and did not work as well when they thought it was a cheap alternative.
American and Canadian researchers found this out by running a double blind study on 12 patients with moderate to severe Parkinson's disease. The patients were told that, in addition to their usual treatment, they were being given a new injectable dopamine agonist, which is a class of drugs used to treat Parkinson's. Half the patients received what they were told was a "cheap" version of the drug and half received an "expensive" version of the drug. They were told that the two drugs were being tested to see if they worked equally well.
The patients were told that one version cost $100 per treatment and the other cost $1,500 per treatment. Actually what they all received was just an injection of saline solution under the skin. Four hours later, the patients who received the "cheap" version got the "expensive" version and vice versa.
When the patients were assessed before and after each treatment using standard tests of Parkinson's symptoms, both versions of the placebo saline solution improved their motor function. Both placebo treatments produced changes in the brain as measured using functional magnetic resonance imaging.
The study found that the expensive placebo injection improved motor function and decreased brain activation (a good thing for Parkinson's) almost on the same level as levodopa, one of the drugs commonly used to treat Parkinson's. "[The] perception of cost is capable of influencing motor function and brain activation in Parkinson disease, the researchers concluded.
The study was published in the journal Neurology.
