MEDICAL MATTERS:Are patients more open and willing to experiment with placebo than doctors think they are, asks Muiris Houston
READERS OF this column will be aware of my interest in placebos and the effect of giving inert or sham treatments. I have argued in the past for our health system to recognise the power of "the doctor as placebo" and to facilitate the use of the phenomenon to increase the likelihood of a treatment achieving its desired effect.
So when the British Medical Journal (BMJ) published a paper online last week - Prescribing placebo treatments: results of a national survey of US internists and rheumatologists - a subsequent headline "Half of doctors routinely prescribe placebos" certainly caught my attention.
The study asked almost 700 specialists in internal medicine and rheumatology in the US a series of questions about their prescription of placebos.
Depending on how the question was phrased, 46-58 per cent of doctors said they used placebos on a regular basis.
Saline injections and sugar pills were used by 3 per cent and 2 per cent of respondents respectively. But the use of vitamins and over-the-counter analgesics was far more prevalent. And perhaps most surprising of all, some 13 per cent of consultants said they had used antibiotics and sedatives as placebos in the previous year.
In the purest sense of the word, a placebo is defined as a sham treatment. Injecting water or giving a tablet made of sugar was considered acceptable medical practice up to the 1960s.
But with an increased emphasis on informed consent and, in more recent times, on the practice of evidence-based medicine, the use of purely inert substances is now considered by some to be ethically unacceptable.
However, the placebo effect is more complex than giving a sham treatment to patients. So the authors of the BMJ research decided to define "placebo treatment" as: "treatment whose benefit [in the opinion of the clinician] derives from positive patient expectations and not from the physiological mechanism of the treatment itself".
This helps to explain, at least in part, the rather high usage of placebo by the US specialists. It certainly opens the door to prescribing vitamins as a placebo. I am less sure about the 40 per cent who said over-the-counter analgesics, such as paracetamol, are placebo treatments. And I definitely have a problem with the use of antibiotics and sedatives as placebos.
The US doctors who recommended a placebo mostly described them to patients as "a medicine not typically used for your condition but which might benefit you". Just one in 10 of those surveyed described the treatment they prescribed to patients as "a placebo".
I am not sure that the description used by most of the doctors could ever hope to elicit a placebo response. The spiel is half-hearted and defensive and falls far short of the doctor investing his own belief in the treatment in a way that might maximise the placebo effect.
It appears I am not alone in my concerns. Online correspondents to the BMJ following the paper's publication have voiced their reservations. "I fear that the iron discipline of evidence- based medicine has deprived us and our patients of the honest and proper use of harmless placebos," wrote one GP.
And doctors from the Department of Biomedical Ethics at the University of Zurich said, in reference to the standard assumption by doctors that openly prescribing placebos is unacceptable to patients, "we urgently need to investigate the patient perspective and compare it to physicians' attitudes. It may turn out patients are much more open and willing to experiment with placebo interventions than is generally assumed."
It may indeed. And who better to ask than readers of HEALTHplus. So I have created a brief scenario below along with some questions which some of you might be kind enough to answer (on a strictly anonymous basis). Please send your replies to mhouston@irish-times.ie; I will provide feedback and discuss the results in a future column.
The scenario
You have been suffering with widespread muscle aches for some months. All medical tests are normal. Your doctor offers to prescribe a sugar pill, which he says has worked for patients with similar symptoms.
1. Would you agree to his proposal?
2. Would you consider his approach unethical?
3. Would you respond differently if the placebo contained an active ingredient such as a vitamin?