A spate of recent studies reinforces the idea that what we think about our
medical care really can affect our health.
The new research into the power of placebos is giving scientists new
insights into how patients’ expectations their beliefs about whether an
inactive, sham treatment will work can have an actual, observable effect on
their well-being.
In one small study, volunteers with jaw pain were repeatedly injected with
what they were told was a pain drug but in reality was nothing but salt
water, yet PET scans showed that after every injection, their brains
produced endorphins natural, opiate-like painkillers.
The men’s beliefs about the treatment caused changes in the brains and
reduced their perception of pain, said Dr. Jon-Kar Zubieta, the study
leader and associate professor of psychiatry and radiology at the
University of Michigan Medical School.
The placebo effect can work in reverse, too, through its evil twin, the
“nocebo” effect. At least 25 percent of the time, when people take an
inactive placebo they report experiencing side effects like headache,
insomnia, and fatigue, said Dr. Arthur Barsky, a psychiatrist at Brigham
and Women’s Hospital. In other words, telling patients about potential side
effects can make it more likely that they’ll occur.
And last week, Harvard researchers reported that sham acupuncture provides
more pain relief than a sugar pill that comes with a promise of relief. The
conclusion to draw from the study, said researcher Ted Kaptchuk, is that
medical ritual “may be a critical component” of treatment.
The work on placebos will help researchers determine precisely what their
drugs are doing and what the contribution of the placebo effect is for
healing though it’s still unclear precisely how best to harness the placebo
effect to make patients feel better.
“The whole point of all this is, how do we capitalize on the placebo
response,” said Dr. Helen Mayberg, a professor of psychiatry and neurology
at Emory University School of Medicine.
The research shows that it’s not possible to “psych yourself” into making a
drug work. But not trusting your care whether it’s popping a pill handed to
you by a doctor or undergoing 30 minutes of treatment from an alternative
medicine practitioner is likely to undermine any benefits.
“This is not about the power of positive thinking, it’s about positive
expectations,” Mayberg said. “I can’t think myself well, but if you go in
with a new treatment and say, `This is not going to work,’ it probably
won’t help you.”
In general, from 30 to 60 percent of patients with everything from
arthritis to depression report an improvement in symptoms after receiving a
placebo. One-third of depressed people feel better after taking placebos,
while 50 to 60 percent of those taking antidepressants do, said Dr. Andrew
Leuchter, vice chairman of the department of psychiatry at the University
of California, Los Angeles.
“The placebo effect is the summation of all the things we do in treatment
that help people get better that are not part of a known specific
treatment,” he said.
“I define it that broadly because when we interact with someone in a
positive way, when we give them encouragement and support, and also when
they become part of the healthcare system no longer sitting at home ill,
but in a milieu where they are getting treatment we tap into positive
expectations.”
The effects of placebos wear off with time, but real drugs keep on working.
Because of this and medical ethics no one is suggesting that doctors
prescribe their patients sugar pills or sham treatments.
But combining real medicines with the “placebo effect” does more than
either can alone.
“The take-home message is that when you get an active drug, you get the
effect of the drug itself and the placebo effect,” said Michigan’s Zubieta.
The newest research, much of it based on brain imaging techniques, provides
direct evidence of how the placebo effect works. The research will help
scientists determine more precisely the contributions of the “placebo
response” to the effectiveness of medications.
Some other recent findings:
Columbia University researcher Tor Wager has used brain scans to map where
in the brain the placebo response occurs. It turns out that those areas
including the thalamus, the insula, and the anterior cingulate cortex are
also among the areas activated when a person is in pain.
The placebo effect can even kick in when there’s no placebo, according to
Dr. Fabrizio Benedetti, a professor at the University of Turin.
In one study, Benedetti hooked pain patients to a computerized injection
device. In some cases, the computer administered morphine without the
patients knowing it, and in others, a doctor gave the drug in full view.
The hidden therapy was much less effective than the open one, showing that
to get the most from a treatment, you have to know you’re getting it.
Similarly, Parkinson’s patients improved more when they were told doctors
were activating a stimulator in their brains than when the stimulator was
turned on without their knowing it, Benedetti showed.
In Alzheimer’s patients, however, the Italian team found the expectation of
pain relief did not reduce the perception of pain, suggesting that a mostly
healthy brain is required for the placebo effect to work.
Though all this makes for compelling research, it’s still unclear what it
means to patients and their doctors. “That’s the new frontier,” Harvard’s
Kaptchuk said.
What is clear is that having a reasonably positive attitude that a new
treatment will work can at least stack the odds in your favor, and not
focusing on all the possible side effects makes sense, too.
It’s also essential to pick a healthcare provider you trust so that his or
her words of encouragement about a treatment can boost the chance it will
work for you.