The Placebo Culture, cont.page 2
Importantly, a subject’s report of change in pain intensity, for example, whether the report is true or false or wishful, is also lumped in as part of the placebo effect phenomenon. The placebo effect is most often simply a subject’s report that he feels better, often as a result of reduced stress from worry about a disease and the subsequent correct adjustment of the body’s normal secretions of feel-good hormones. Handsomely funded research studies allow researchers to acquire positron emission tomography, magnetic resonance imaging, electrocardiograph , or encephalogram equipment that can measure pain intensity before and after introduction of experiment stimuli as a presumed function of heat and chemical activity in the brain; such measures are more accurate than self-reports, though the brain activity in those suffering chronic pain may actually be lower due to habituation effects.
Experiments in which the placebo effect must be considered are primarily studies of new drugs (clinical drug trials) to show the effectiveness, or efficacy, of a new drug compared to no drug or a competing drug whose efficacy is known through prior testing. Pharmaceutical research teams pit their new drug formulations against placebos to determine if the new drug is effective. The placebo effect forces researchers to set up an entire control group just to determine what percentage of a response can be attributed to human subject psychological-based factors, so that that percentage can be factored out of the results of the tested experimental condition. If healing is no more effective than what one would expect from the placebo effect, then the new drug is ineffective.
Placebo control groups aren’t needed in laboratory drug trials run on rats: rats don’t suffer from the same psychological delusions that people do. Give a dog a chew bone and tell him you’ve replaced the marrow with a drug that will cure his limp, and the dog will limp back for a second bone.
If human psychology (the ability of the mind to temporarily fool the body), suggestibility, gullibility, emotional instability, desire to get better, and desire to please authority contribute to the skewing of drug trial results, human error—and not potential flaws in the scientific method—explains why we should be skeptical of placebo study results.
Subjects may also experience the opposite of a positive placebo effect, what researchers have termed a nocebo, in which patients report negative side effects from drugs merely because they expect to. Clinical-trial “participants reported a wide variety of nocebo complaints, including burning sensations, vomiting and even upper-respiratory-tract infections. Many participants reported these problems even when they were part of control groups that were taking a sugar pill. Other research has shown that when doctors tell patients a procedure will be painful, those patients report more pain than patients not similarly warned.” (Cloud, p. 57). Still others report fatigue after taking a drug, though fatigue isn’t a recognized effect of taking the drug.
Placebos might help heal, so why not use them? Because they might not. They might be nocebos because a specific patient’s thinking about the placebo is unknowable and may be affected by an individual’s brain structure and genetic interactions.
In one flawed study published in Journal of Neuroscience, people with social phobias who were most susceptible to placebos (meaning only those few in placebo control groups who indicated positive results) experienced a significant reduction after eight weeks in the amygdala’s activity during an oral speech they had rehearsed and presented to the researchers, compared to pre-placebo administration PET scans. The study also suggested that two genes–the serotonin transporter gene and the tryptophan hydroxylase-2 gene–might have an effect on the activity in the amygdala that influences the propensity to respond to a placebo.
“The effect of placebos is most apparent in the treatment of pain” (Thomas, p. 13), such as an unspecified chest pain (angina pectoris). Angina pectoris differs from exertional angina, which is often the result of myocardial ischemia or perfusion, a condition in which the amount of oxygen that the heart requires isn’t met by the flow of blood due to coronary artery blockage (atherosclerosis), a condition in which improved blood flow can be measurably detected in about 8% of patients who receive a placebo, meaning that the blood flow improvement can be attributed to any factor in the studied patient’s life over the course of 8 weeks of study, even self-healing and exercise. Even placebo surgeries in which nothing but an incision was made in the skin had comparable alleviative effects to actual surgery to litigate the internal mammary artery in the treatment of angina pectoris.
Pain, in most cases, is at its most intense at its peak, just before it begins to lessen. When pain is at its peak is when most people seriously seek relief and then mistakenly believe that the reduction in pain can be attributed to the agent of their relief, even if such medical treatment is a sham, such as a magnet belt or chiropractic spinal manipulation. Throughout a disease’s progression, patients will experience good and bad days, regardless of the effectiveness of the medication they’re taking.
Acupuncture success can be attributed to spontaneous, temporary, or cyclical remissions and the human body’s self-adaptive healing processes.
Because patients psychologically experience pain, they also psychologically experience the degree of pain relief based on the degree of the intervention. Large pills work better as placebos than small pills. Invasive injections work better than pills, and surgery placebos are seen to have the greatest pain diminishment because surgery is seen as the complete removal of whatever is causing the pain, as opposed to a simple treatment to lessen the severity of the pain. Also, lengthy treatments are seen as more effective, and thus self-fulfill as more effective, than quick fixes.
In spite of all of the possible factors that confound results in placebo effect testing, some writers still think that believing “in a cure leads to real bodily changes. The brain opens opiate receptors in response to faux pain pills, boosts dopamine in response to sham Parkinson’s surgery and even prods tumors to shrink if a patient has faith in an ineffective drug” (Cloud, p. 66). “Scientists are coming to understand the placebo response as a cascade of neural reactions that not only provide psychological relief but also play a physiological role in blocking stress hormones that damage the body. In clinical trials, most drug responses are now assumed to be partly due to the placebo effect” (Cloud, p. 57).
However, opiate receptors open and close naturally and tumors change size, with or without belief in a medical procedure, and dopamine is also released in times of stress, such as trepidation about a surgical procedure. Believing in a cure is calming, which slows the body’s production of adrenaline, which in turn slows the action of the nerves and bowels and blood pressure, which in turn reduces the flow of nutrient-rich blood to cancer cells. Of course, there is no valid control group to test if belief or acceptance causes bodily biological changes.
Personal testimonials that a sugar pill has cured an illness or disease (differentiated from illness based on a “pathological state of the organism due to infection, tissue degeneration, trauma, toxic exposure, carcinogenesis, etc.” [Beyerstein]) offer no foundation on which to judge the curative value of any therapy. People get better and mistake the co-occurrence or subsequent diminishment of pain as the result of the placebo, though any number of factors may be involved.
One meta study by Danish researchers of 114 other studies involving placebos found little evidence that placebos provided significant medical benefit, compared with no treatment, regardless of whether outcomes were self-reported or measured with medical equipment (Hrobjartsson and Gotzsche).
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