Over the past several years, there’s been a public argument
happening between science and religion on a variety of points. As a physician,
I take a non-partisan stance in this debate, and simply want to know what works
so that I can best help my patients - as a favorite teacher of mine used to
say, ‘There’s no room for dogma in medicine.’ With that in mind, let’s see what
happens when religion and science mix directly, in the form of intercessory prayer
to achieve health outcomes.
Let’s take a look first at some studies that show positive
benefit. One study I came across was done to measure the effect of intercessory prayer on aiding South Korean women undergoing IVF in an effort to become pregnant. 219 women were randomized to either a prayer group or a control group.
Interestingly, the women were not informed that they were taking part in a
study, nor were their healthcare providers. The prayer groups were located in
Canada, Australia and the United States (some distance from South Korea). The
study found that the group receiving the prayer intervention achieved implantation
and became pregnant at nearly double the rate that their non-prayed-for
counterparts did. One of the points this study illustrates is that prayer
apparently doesn’t have to happen locally to demonstrate benefit.
A quite large study, done in Israel, was published in the British Medical Journal that looked at
3393 adult patients with bloodstream infections (sepsis). An interesting aspect
of this study is that the prayer was done retroactively – 4-10 years after the
episodes occurred. This intervention was done on the argument that God was not
limited by linear time the way we are, and that we could not assume that time
was linear in any event. The study found a minor trend towards decreased
mortality among the group receiving prayer, but this was not statistically
significant. However, the length of stay in the hospital and duration of fever
among the group receiving prayer were both shorter. The duration of fever was
mildly shorter among the intervention group, but the length of hospital stay in
the intervention group was remarkably shorter, especially as one reached the
more severe levels of disease.
One of my favorite studies on this topic was done on bush babies who displayed a condition called chronic self-injurious behavior – a
condition characterized by excessive self-grooming that results in the
formation of skin lesions, being something like a non-human
obsessive-compulsive disorder. Twenty-two bush babies were assigned to receive
either l-tryptophan alone, or l-tryptophan and intercessory prayer for four
weeks. After the four weeks, researchers found that the bush babies receiving
prayer in addition to conventional treatment had a reduction in wound size
compared to their counterparts, engaged in less wound-grooming, and less
grooming behaviors overall. The authors noted that because the study was done
on non-human animals, the results were not susceptible to the effects of
placebo, as they might have been in a human trial.
Here's a pic of Otolemur garnetii, the type of bush baby studied
Obviously, however, not all studies have shown benefit. A
study done among kidney dialysis patients showed that intercessory prayer could
not be distinguished from the effect of expectancy (sometimes called ‘placebo’)
in improving medical or psychological measures of patient’s well-being, and a study of HIV patients that included intervention by professional healers,
untrained nurses, or no intervention found that there was no benefit to prayer
among study participants, and no clinical outcome could be attributed to the
prayer. We shouldn’t be surprised that some studies have shown no benefit, as
almost all treatments have tested poorly at one point or another.
One interesting focus of study has been on cardiac patients
in the hospital. A study was published in 1999 in the Archives of Internal Medicine which suggested that intercessory
prayer might improve a patient’s experience in the coronary care unit. In the
study, 990 patients were randomized into intervention or placebo groups without
their knowledge, and either did or did not receive intercessory prayer while
they were in the hospital. While the length of CCU and hospital stay did not
vary between groups, the patients in the prayer group had lower CCU course
scores, which basically means that they had fewer adverse events in the course
of their stay. However, a year later, the Mayo Clinic published a similar study
which found no significant benefit from intercessory prayer among 799 CCU
patients.
These findings caught the eye of researchers at Harvard’s
Medical School, and so they set up a similar study with one twist – that along
with the patients who were blinded as to whether or not they would receive
prayer, a third arm of patients would be told they would be receiving prayer,
and did receive prayer. This study was the largest of all, with a total of 1802
patients being involved. However, not only did this study find that prayer did
not reduce complications in patients receiving CABG (commonly known as bypass
surgery), nor did it change mortality after surgery, but in fact, being certain
that one was receiving prayer was associated with a higher incidence of complications. The study authors brushed off
this as a fluke, but needless to say, this was not good news. In reaction to the published results, commentators noted that participants’ concealing from
their providers the fact that they were being prayed for may have caused this
increase in complications. This study is confusing at best, troubling at worst,
and needs further examination, as the commentators called for.
What happens when we put this all together? A Cochrane Systematic Review looked at 10 studies on intercessory prayer for patients
already receiving routine care for a variety of conditions. Not unexpectedly,
the review noted that the results were mixed, and that although some studies
showed positive results, others showed no result. The review declared that
there was not enough data to recommend either in favor or against of the use of
prayer to improve health. The authors went on to say that resources available
for the study of prayer should be better devoted to other questions in health
care. The Cochrane Review is a very high quality, but largely scientifically
conservative organization, and their commentary is unsurprising.
So what’s my opinion after reading all of this literature? I
think you ought to pray if the spirit moves you. A few studies have noted
beneficial effects. A few have noted no measurable effect. I think that the one
outlier study, which showed a negative effect needs a critical reexamination –
the authors brushed off the negative effect, but I think it’s worth taking a
good hard look and trying to determine what factors may have caused the
negative effect (I’m inclined to believe that the stress of concealing
information from one’s providers while undergoing major surgery may have been
part of the cause). In the future, research into this topic should be improved
– a few studies have noted a measurable beneficial effect, and I think we need
to nail down factors that influenced that positive effect, a process that will
require further quantifying and describing the prayer process. I have no
illusions that this will remain on the back burner for researchers, and some
might argue that quantifying prayer defeats the whole point, but I think that
there’s enough evidence that something
is going on that we should work to figure it out.