We are inundated with new information regarding health-related studies on an almost daily basis. Often the results are exactly as one expects, but occasionally, findings are published that are so counter-intuitive, it makes ones jaw drop to the space bar. Such is the case with an article published in the world renowned Journal of the American Medicine Association entitled, “Number of Coronary Heart Disease Risk Factors and Mortality in Patients With First Myocardial Infarction”. The study’s findings, based on follow-ups of over a half a million heart attack patients, were astonishing, and that’s putting it mildly.
What the study hoped to quantify was the probability of someone dying of their very first heart attack, given the presence or absence of five well known risk factors. These risk factors are as follows:
high cholesterol, diabetes, elevated blood pressure, smoking, and having a family history of heart failure.
One would assume, going into this study, that the results would be obvious; a “no-brainer” as they say. It seems reasonable, the more of those five risk factors the patient possesses, the more likely the last thing they will see after a heart attack, is a guy with a white mask hovering over him, paddles in hand, saying, “We lost him.”
However, unbelievably, the exact opposite is true. Based on the incontrovertible data, from the enormous survey sample size, the death rate for someone with no risk factors is almost five times higher than those patients who present all of them. Here’s how it breaks down by number of risk factors.
If you engage in a risky lifestyle; you smoke, eat lots of fatty foods, never exercise, have diabetes and have relatives with bad tickers, the chance of you dying in hospital from your first heart attack is 3.6%. If you did all that except for, say, you were a non-smoker, but still exhibited the other four risks, your odds go up to 4.2%. With three risks, 5.3%, two risks jumps to 7.9% and with just one risk factor, your chance of dying is 10.9%. What if you are one of the minority, the less than 15% of the population who have no risk factors at all? In that case, your chance of dying on your first try is a whopping 14.9%!
It is not like this was just some screwball data from a small sample group with figures extrapolated to magnify the numbers. The methodology was impeccable and the 542,008 cases studies were certainly large enough to carry the weight of the findings. In fact, the authors of the report, there were thirteen listed, including lead researcher Dr. John G. Canto, MD, MSPH, stated in their comments that they believed this to be the single largest study to date, examining mortality rates and other outcomes from admissions to community hospitals in America.
In a world awash in data, with precious little real information to show for it, it is not surprising the experts in many fields sometimes disagree over what it all means. The public is constantly pelted with reports, what foods are good, bad or indifferent, and the lists often disagree with one another. Last week’s pronouncement that coffee is worse than poison is followed in the next week by another so-called “expert” extolling the virtues of the beverage on human health. The reasons for the discrepancies are varied and can even include the bias of the source, besides, simply the quality of the studies being discussed.
Considering the huge difference between mortality rates of those with no risk factors and people who have the complete set, what should we make of this new information? Obviously, no doctor will recommend you take up tobacco use or try out the “Supersize Me” diet. Still, how can they ignore the findings when they are so unambiguous?
Some researchers in the report did speculate that when a human is involved with any or all of the risk factors, the behavior stresses the heart in ways that makes it prepare for a critical episode. “Health nuts”, with their sterling circulatory systems, on the other hand, exhibit a great deal more cardiac shock during a critical failure than their less healthy counterparts who, apparently, are used to abuse.
There may be other reasons, however. One possibility is that people with zero risk factors or behaviors may not be as likely to seek medical attention as quickly as chronic medical users which the multi-risk population are more likely to be. Indeed, in the journal report, they did allude to the fact that zero risk patients were less likely to receive invasive heart attack treatment as quickly as their riskier brethren. With the high risk patients, medical practitioners leaped to the heart attack diagnosis much quicker, since that group fits the patient profile for a heart attack victim much better than their healthier lifestyle fellows.
The study’s researchers also made the point that as the population ages, they are more likely to cease risky behaviors they once did. Perhaps this may, at least partially account for the dichotomy. One would expect that the younger a person, irrespective of their lifestyle, the better their chance of recovering from a major cardiac episode.
Whatever is the cause of the seemingly skewed statistics regarding mortality rates and risk factors, the researchers did not explore the quality of life these individuals had on their way to their first heart attack. Nor do they mention how many of the people with no risk factors were saved from debilitating cancers or other diseases unrelated to cardiac arrest. Without knowing more information, this surprising finding becomes something of a statistical curiosity, but is not information one should use to change their risk factor exposure. It’s just one more piece of a very complex puzzle.