The "nocebo effect" is the lesser-known opposite number of the placebo effect, and describes any case where putting someone in a negative frame of mind has an adverse effect on their health or well-being. Tell people a medical procedure will be extremely painful, for example, and they will experience more pain than if you had kept the bad news to yourself. Similarly, experiences of side effects within the placebo groups of drug trials have shown that a doctor's warning about the possible side effects of a medicine makes it much more likely that the patient will report experiencing those effects.
This is not just in the mind: it is also about physical effects. The stress created by the nocebo effect can have a long-lasting impact on the heart, for example – perhaps serious enough to cause fatal damage.
In the 1970s, for example, doctors diagnosed a man with end-stage liver cancer, and told him he had just a few months to live. Though the patient died in the predicted time, an autopsy showed the doctors had been mistaken. There was a tiny tumour, but it had not spread. It seemed the doctors' prognosis had been a death curse. http://www.newscientist.com/article/mg20327247.100-13-more-things-the-nocebo-effect.html
A nocebo (Latin for "I will harm") is something that should be ineffective but which causes symptoms of ill health. A nocebo effect is an ill effect caused by the suggestion or belief that something is harmful. The term 'nocebo' became popular in the 1990s. Prior to that, both pleasant and harmful effects thought to be due to the power of suggestion were usually referred to as being due to the placebo effect. http://www.skepdic.com/nocebo.html
• More than two-thirds of 34 college students developed headaches when told that a non-existent electrical current passing through their heads could produce a headache.
• "Japanese researchers tested 57 high school boys for their sensitivity to allergens. The boys filled out questionnaires about past experiences with plants, including lacquer trees, which can cause itchy rashes much as poison oak and poison ivy do. Boys who reported having severe reactions to the poisonous trees were blindfolded. Researchers brushed one arm with leaves from a lacquer tree but told the boys they were chestnut tree leaves. The scientists stroked the other arm with chestnut tree leaves but said the foliage came from a lacquer tree. Within minutes the arm the boys believed to have been exposed to the poisonous tree began to react, turning red and developing a bumpy, itchy rash. In most cases the arm that had contact with the actual poison did not react." (Gardiner Morse, "The nocebo effect," Hippocrates, November 1999, Hippocrates.com) [please see reader comments]
• In the Framingham Heart Study, women who believed they are prone to heart disease were nearly four times as likely to die as women with similar risk factors who didn't believe.* (Voelker, Rebecca. "Nocebos Contribute to a Host of Ills." Journal of the American Medical Association 275 no. 5 (1996): 345-47. ) [Of course, one might argue that the women in both groups had good intuitions. The objective risk factors may have been the same, but subjectively the women knew their bodies better than the objective tests could reveal.]
• C. K. Meador claimed that people who believe in voodoo may actually get sick and die because of their belief ("Hex Death: Voodoo Magic or Persuasion?" Southern Medical Journal 85, no. 3 (1992): 244-47).
• "In one experiment, asthmatic patients breathed in a vapor that researchers told them was a chemical irritant or allergen. Nearly half of the patients experienced breathing problems, with a dozen developing full-blown attacks. They were “treated” with a substance they believed to be a bronchodilating medicine, and recovered immediately. In actuality, both the “irritant” and the “medicine” were a nebulized saltwater solution."
• Double-blind, controlled studies have repeatedly shown that electro-sensitives can't tell the difference between genuine and sham electro-magnetic fields (EMFs).1, 2 For example, a research team in Norway (2007) conducted tests using sixty-five pairs of sham and mobile phone radio frequency (RF) exposures. "The increase in pain or discomfort in RF sessions was 10.1 and in sham sessions 12.6 (P = 0.30). Changes in heart rate or blood pressure were not related to the type of exposure (P: 0.30–0.88). The study gave no evidence that RF fields from mobile phones cause head pain or discomfort or influence physiological variables.
• About 20% of patients taking a sugar pill in controlled clinical trials of a drug spontaneously report uncomfortable side effects — an even higher percentage if they are asked.
• Arthur Barsky, a psychiatrist at Boston's Brigham and Women's Hospital, found in a recent review of the nocebo literature that patient expectation of adverse effects of treatment or of possible harmful side-effects of a drug, played a significant role in the outcome of treatment (Barsky et al. 2002).
In medicine, a nocebo reaction or response refers to harmful, unpleasant, or undesirable effects a subject manifests after receiving an inert dummy drug or placebo. Nocebo responses are not chemically generated and are due only to the subject's pessimistic belief and expectation that the inert drug will produce negative consequences. In these cases, there is no "real" drug involved, but the actual negative consequences of the administration of the inert drug, which may be physiological, behavioural, emotional, and/or cognitive, are nonetheless real. The term nocebo (Latin for "I will harm") was chosen by Walter Kennedy, in 1961, to denote the counterpart of one of the more recent applications of the term placebo (Latin for "I will please"); namely, that of a placebo being a drug that produced a beneficial, healthy, pleasant, or desirable consequence in a subject, as a direct result of that subject's beliefs and expectations. http://en.wikipedia.org/wiki/Nocebo
The Nocebo Effect ~ http://harvardmagazine.com/2005/05/the-nocebo-effect.html
The Biochemical and Neuroendocrine Bases of the Hyperalgesic Nocebo Effect ~ http://www.neuro.cjb.net/content/26/46/12014.full
Warnings about insomnia and stress are naturally more likely to induce stress and insomnia, of course, but victims of the nocebo effect report depression, fatigue, nausea, and chronic pain. Those who were told that medical procedures would be painful reported more pain than those who were told that the procedures would be relatively painless. ~ http://io9.com/5639545/plan-the-perfect-murder-with-the-nocebo-effect
Cause leads; effects follow!
Thought is the cause; conditions are the effects!
No comments:
Post a Comment