Trick or Treatment—The Undeniable Facts about Alternative Medicine (Electronic book text)

Interest in the placebo effect grew over the course of the nineteenth century, but it was only in the 1940s that an American anaesthetist named Henry Beecher established a rigorous programme of research into its potential. Beecher’s own interest in the placebo effect was aroused towards the end of the Second World War, when a lack of morphine at a military field hospital forced him to try an extraordinary experiment. Rather than treating a wounded soldier without morphine, he injected saline into the patient and suggested to the soldier that he was receiving a powerful painkiller. To Beecher’s surprise, the patient relaxed immediately and showed no signs of pain, distress or shock. Moreover, when morphine supplies ran low again, the sly doctor discovered that he could repeatedly play this trick on patients. Extraordinarily, it seemed that the placebo effect could subdue even the most severe pains. After the war, Beecher established a major programme of research at Harvard Medical School, which subsequently inspired hundreds of other scientists around the world to explore the miraculous power of placebos.

As the twentieth century progressed, research into placebo responses threw up some rather shocking results. In particular, it soon became clear that some well-established treatments benefited patients largely because of the placebo effect. For example, in 1986 a study was conducted with patients who had undergone tooth extraction, and who then had their jaw massaged by an applicator generating ultrasound. These sound waves, whose frequency is too high to be heard, could apparently reduce post-operative swelling and pain. Unknown to the patients or the therapists, the researchers tampered with the apparatus so that there was no ultrasound during half of the sessions. Because nobody can hear ultrasound, those patients not receiving ultrasound did not suspect that anything was wrong. Astonishingly, patients described similar amounts of pain relief regardless of whether the ultrasound was on or off. It seemed that the effect of the ultrasound treatment was wholly or largely due to the placebo effect and had little to do with whether the equipment was working. Thinking back to Haygarth’s criteria for a good placebo, we can see that the ultrasound equipment fits the bill — dentists had promoted it as effective, it looked expensive and it was novel.

An even more startling example relates to an operation known as internal mammary ligation, which was used to relieve the pain of angina. The pain is caused by a lack of oxygen, which itself is caused by insufficient blood running through the narrowed coronary arteries. The surgery in question was supposed to tackle the problem by blocking the internal mammary artery in order to force more blood into the coronary arteries. Thousands of patients underwent the operation and afterwards stated that they suffered less pain and could endure higher levels of exercise. However, some cardiologists became sceptical, because autopsies on patients who eventually died revealed no signs of any extra blood flow through the remaining coronary arteries. If there was no significant improvement in blood flow, then what was causing the patients to improve? Could the relief of symptoms be due simply to the placebo effect? To find out, a cardiologist named Leonard Cobb conducted a trial in the late 1950s that today seems shocking.

Patients with angina were divided into two groups, one of which underwent the usual internal mammary ligation, while the other group received sham surgery; this means that an incision was made in the skin and the arteries were exposed, but no further surgery was conducted. It is important to point out that patients had no idea whether they had undergone the real or sham surgery, as the superficial scar was the same for both. Afterwards, roughly three-quarters of the patients in both groups reported significantly lower levels of pain, accompanied by higher exercise tolerance. Incredibly, because both real and sham operations were equally successful, then the surgery itself must have been ineffective and any benefit to the patient must have been induced by a powerful placebo effect. Indeed, the placebo effect was so great that it allowed patients in both groups to reduce their intake of medication.

Although this suggests that the placebo effect is a force for good, it is important to remember that it can have negative consequences. For example, imagine a patient who feels better because of a placebo response to an otherwise ineffective treatment — the underlying problem would still persist, and further treatment might still be necessary, but the temporarily improved patient is less likely to seek that treatment. In the case of mammary ligation, the underlying problem of narrowed arteries and lack of oxygen supply still existed in patients, so they were probably lulled into a false sense of security.