On the flip side, what if your
doctor knew that statistically patients who are gradually weaned off of a
chronic pain medication by decreasing their dosage until it is a placebo will
still experience relief from their pain as a result of habituation? Should the
doctor lie to you about your dosage in an effort to help your chronic pain
while mitigating side effects?
Mark Alfano, bioethicist at Delft
University of Technology in the Netherlands writes a compelling argument for
re-defining our views of placebos and placebo effects and how, by defining them
in terms of classical conditioning, expectation fulfilment, and somatic
attention and feedback, the ethics of informed consent changes by doing so. His
is the target article in this month's issue of the American Journal of
Bioethics...
However, placebo effects are real
phenomena caused by neurobiological and psychological factors, many of which
are specific. Research provides many examples of how certain interventions or
suggestions, considered placebos, produce specific results.
Alfano lays out three psychological mechanisms that are
known causes for placebo effects. The first is expectation-confirmation. This
is when a patient believes that a certain treatment will help in a certain way.
In some cases, because the patient has a preconceived notion about the efficacy
of the treatment, it will influence the patient's capacity for
"self-cure." For example, one study found that patients experienced
more pain relief from name-brand aspirin than from generic aspirin because
advertising and reputation lead the patients to expect the name-brand aspirin
to work better. Functional MRI studies showed that there was a difference in
brain activity within the pain centers of the brain based on an expectation of
pain relief versus an expectation of more pain whether the pills had active
ingredients or not, demonstrating a physiological effect based on expectation
bias.
The next type of psychological mechanism responsible for
placebo effects is classical conditioning, or habituation. This is when the
body learns to respond in a certain way to a stimulus, such as taking a pill of
a certain size and color. One example in the literature is with psoriasis
treatment. Psoriasis is a skin condition that presents as a rash and is
triggered by various stimuli, including stress. In one study, subjects were
given the full dosage of medicine to control their psoriasis. Their dosage of
active ingredient gradually decreased until the subjects were taking a placebo.
The physiological effects were the same as when the subject was taking the full
dose.
Somatic attention and feedback is another psychological
mechanism and has to do with how much attention a person pays a particular
stimulus. The way the person interprets that stimulus depends on his or her
views on its importance. Often the patient's interpretation will dictate
whether they are experiencing pain or pain relief and whether pain is from side
effects or another medical condition. This mechanism will often lead to actual
relief because, by construing something as relieving, it may actually induce
physiological changes from decreased stress and anxiety.
Given these various causes of the placebo effect, Alfano
suggests that what is broadly termed the "placebo effect" should be
investigated as separate groups based on its psychological cause. Furthermore,
by investigating these phenomena, doctors can have empirical evidence for when
it would serve the patient's best interest to employ confirmation-expectation
bias, classical conditioning, or somatic attention and feedback as part of the
patient's overall treatment.
Alfano points out that this is not a reversion to
paternalism, but is more about managing expectations and mitigating the amount
of information a patient receives. More information is not always better, and
in some cases, can have adverse effects. Respecting patient autonomy may
involve getting patient permission to not describe the side effects because
studies have shown that a patient is less likely to experience side effects if
he is not aware of them. The caveat to this is that the side effects must be
trivial or symptomatic, or some other options must be in place in case the
patient does experience side effects.
Importantly, incorporating these three different groups need
not involve deception on the physician's part. Managing expectations does not
require lying, deceiving or misleading someone. For example, Classical
conditioning works even if you know you are being conditioned to a response
since it is similar to forming a habit. Even in cases of somatic attention, the
doctor could nudge or frame the situation in such a way as to change the
patient's perspective, what Cass Sustein and Richard Thaler describe as
libertarian paternalism. In this sense, the patient still has the option to
choose the doctor's suggested treatment or not, but will benefit from the way
the doctor frames the treatment.
Alfano's article offers a paradigm shift in the way that
placebos and placebo effects are typically viewed, and opens the door to
further studies into the effects of these three psychological mechanisms, as
well as others, that promote efficacy of treatments. These placebogenic
practices are not alternatives to traditional treatments, but can be used to
enhance treatments.
http://medicalxpress.com/news/2015-10-re-framing-placebo-effect-consent.htmlAlfano M. Placebo Effects and Informed Consent. Am J Bioeth. 2015
Oct;15(10):3-12.
Abstract
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