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The Science of Medicine
Treatment and recovery: Cause and effect?
If one event comes immediately before another, people naturally assume the first is the cause of the second. For example, if a person pushes an unmarked button on a wall and a nearby elevator door opens, the person naturally assumes that the button controls the elevator. The ability to make such connections between events is a key part of human intelligence and is responsible for much of our understanding of the world. However, people often see causal connections where none exist. That is why athletes might continue to wear the "lucky" socks they had on when they won a big game, or a student might insist on using the same "lucky" pencil to take exams. This way of thinking is also why some ineffective medical treatments were thought to work. For example, if an ill person’s fever broke after the doctor drained a pint of blood or the shaman chanted a certain spell, then people naturally assumed those actions must have been what caused the fever to break. To the person desperately seeking relief, getting better was all the proof necessary. Unfortunately, the apparent cause-and-effect relationships observed in early medicine were rarely correct, but belief in them was enough to perpetuate centuries of ineffective remedies. How could this have happened? People get better spontaneously.Unlike “sick” inanimate objects (such as a broken axe or a torn shirt), which remain damaged until repaired by someone, sick people often get well on their own (or despite their doctor’s care) if the body heals itself or the disease runs its course. Colds are gone in a week, migraine headaches typically last a day or two, and food poisoning symptoms may stop in 12 hours. Many people even recover from life-threatening disorders, such as a heart attack or pneumonia, without treatment. Symptoms of chronic diseases (such as asthma or sickle cell disease) come and go. Thus, many treatments may seem to be effective if given enough time, and any treatment given near the time of spontaneous recovery may seem dramatically effective. better. Pain, nausea, weakness, and many other symptoms can diminish even if a pill contains no active ingredients and can be of no possible benefit, such as a "sugar pill" (termed a Placebos ). What counts is the An ineffective (or even harmful) treatment prescribed by a confident doctor to a trusting, hopeful person often results in remarkable improvement of symptoms. This improvement is termed the placebo effect. Thus, people might experience anactual(not simply perceived) benefit from a treatment that has had no obvious effect on the disease itself. Current research suggests there is a biologic basis for the placebo effect in some disorders, even though that effect is not targeting the actual disease. Why does it matter?Some people argue that the only important thing is whether a treatment makes people feel better. It does not matter whether the treatment actually “works,” that is, affects the underlying disease. This argument may be reasonable when thesymptomis the problem, such as in many day-to-day aches and pains, or in illnesses such as colds, which generally go away on their own. In such cases, doctors do sometimes prescribe treatments that have little effect on the disease and, instead, may at least in part relieve symptoms due to the placebo effect. However, in any dangerous or potentially serious disorder, or when the treatment itself may cause side effects, it is important for doctors to only prescribe a treatment that really does work. A treatment's potential benefits must be balanced against its potential harms. For example, drugs with many side effects may be worth taking for people with life-threatening diseases, such as cancer. Some cancer drugs may cause serious damage, such as to the kidneys or heart, but these risks are often acceptable because the alternative to the drugs (the effects of untreated cancers), is likely worse than the drug side effects 