I am deeply concerned regarding the frequent misuse by the medical field of the words “cause” and “causal.” As succinctly as possible: cause and effect means that if A, then B. It does not mean, if A then maybe B!
While depression would certainly be a factor in exacerbating or even bringing out incipient disease, to state depression as causal is improper and scientifically absurd—the misuse of “cause/causal” costs this culture millions of dollars, a great deal of heartache to the population, and the rising fear of litigation when we, the misusers of the concept, do not deal with each and every one of the “causes” of disease.
Coronary artery disease, and most other diseases for that matter, is a multi-factorial problem. This means that there is no single causative factor. While falling down the steps and breaking a leg can be regarded as having broken because of the fall (ie, cause-effect), disease is not as simple as injury. I belie myself here in that the fracture is also dependent on the speed of the trauma, the angles of the trauma, and even the integrity of each person's bones, etc. In physics, we are at least aware that we are unlikely to “know” all of the variables and the “hidden variable” theory reminds us that we rarely have full knowledge of all variables and that there are actually very few instances of only one variable.
I have been in practice since 1977 and every “cause” of disease that researchers report and the journals reinforce would be more correctly regarded as contributing or aggravating factors, or perhaps better stated as “players in the game.”
Remember: When I throw an object up while standing on the Earth, it will fall down! It does so 100% of the time, and also it does not jump up on it's own. We therefore can properly say that gravity causes the object to fall. However, imagine if the object came down only 80% of the time. Would we say gravity causes or contributes? What if the object came down only 10% of the time?
Too many articles report small percentages of difference in results, which are then related as causal, to whatever variable is being investigated. We help no one by misusing this concept. I appeal to both the medical researchers as well as the reporting journals to change our wording and therefore implications. I appeal to the physicians in the trenches, my comrades in arms, as it were, to understand that we should not reinforce the idea of cause and effect to our patients unless it meets the criteria of if A then B.
Overweight is certainly less than healthy, but there are many overweight individuals who will not develop diabetes, hypertension, etc. One of the latest reports I read stated that only about 11% of smokers get lung cancer and a similar percentage get COPD. That leaves a good almost 70% or more who do not get these illnesses. While we should not support lifestyles that are risky, we injure our own credibility as physicians by stating what the layman intuitively knows are gross exaggerations—and furthermore, the legal system uses against us.
This is not suggesting that the research is poor and inappropriate. It is suggesting that we should be more scientifically correct in ascribing cause and effect. It is suggesting that we remember that there are very few disease states that have only one variable. It is suggesting that we stop forcing all statically valid results into cause-effect single variable models. These ideas limit our own, as well as the layman's understandings and beliefs.
Statistical validity is not sufficient to prove causality. It is we, the professionals who must lead by educating, that know there is no gain on any level to our labeling minor and even significant variances and variables as singular causes.
Barry Marged DO, MA, ABD