In the world of EMS and the Emergency Department, the treatment of an acute MI or STEMI can get your own pulse going.
We have many tools and treatments at our disposal for these cases. Many of the treatments, such as defibrillation, dopamine, and stenting — well — they are kind of sexy. Rarely included in the “sexy” category are the drugs called statins. It’s my hope to give you a new insight into this class of medication, and to be able to sort between the hype and the reality of statins. For pharmaceutical industries, statins are a huge business, with sales in the billions.
Since statins work in part by lowering cholesterol levels, I first want to talk about how cholesterol and heart disease became entwined. In the early 1960s, there seemed to be a flood of young men dying prematurely from heart disease. Indeed, in 1969, this upward trending of premature death was described by the World Health Organization as potentially “the greatest epidemic mankind has faced.”
With intense investigation, many things were proposed as causes (more about causation later) for this dramatic rise. A few of the proposed causes included:
- Sedentary lifestyle
- High cholesterol
- Smoking
- High-fat diets
- Stressful professions
After relentless research, it was found that people with high total cholesterol have approximately twice the risk of heart disease as people with optimal levels. Also, in the young men killed in the Vietnam War, it was noted that many had cholesterol-filled plaques in their coronary arteries, setting the stage for later heart disease. Cholesterol rose to the top of the list as a potential culprit.
Why is cholesterol important?
From Wikipedia: “Cholesterol is a waxy steroid of fat that is produced in the liver or intestines. It is used to produce hormones and cell membranes and is transported in the blood plasma of all mammals. It is an essential structural component of mammalian cell membranes and is required to establish proper membrane permeability and fluidity. In addition, cholesterol is an important component for the manufacture of bile acids, steroid hormones, and vitamin D.”
Obviously, cholesterol is important stuff. But when diseased coronary arteries are examined, the plaques were noted to be full of cholesterol. It wasn’t completely unreasonable to think that by reducing cholesterol we will reduce heart disease.
Approximately one in every six adults — 16.3 percent of the U.S. adult population — has high total cholesterol, which is defined as 240 mg/dL and above. This has spurred a quest to find ways to lower cholesterol.
The cholesterol in our body comes from two sources – from the cholesterol we consume in our food, and from the cholesterol that our own body manufactures. What may surprise you is that our own body is responsible for the large majority of our cholesterol (about 75 percent), and not what we eat.
As you might suspect, efforts to lower cholesterol by modifying diet alone met with limited success. Efforts were then focused on trying to disrupt the manufacturing of cholesterol by our own bodies, and statins were born.
Effects of statins on mortality
Statins act by disrupting parts of the manufacturing of the cholesterol in our body, blocking a critical enzyme called HMG-CoA reductase. They are often highly effective at lowering cholesterol levels.
If you have already had a problem with your heart (MI, stents, etc), statins work in decreasing your mortality. Interestingly, they can be a benefit even if your cholesterol levels don’t drop much – which is why some people have postulated that there must be something else (perhaps inflammation) that is responsible for the accelerated heart disease.
If you have already had a heart attack, statins clearly work, decreasing your risk of a second heart attack by about one third, although it remains unclear as to exactly why they work.
If you don’t have any heart disease, statins can lower your cholesterol, but don’t necessarily have a dramatic effect on your mortality. One study that looked at statin use for primary prevention (translated: no prior heart disease) showed that if 100 people took a statin for three and a half years, just one less person would have a cardiac attack. Of course, that’s great for that one person, but is it an expensive proposition with no benefit, not to mention the potential side effects, for the other 99.
Correlation does not imply causation
As human beings, it is in our nature to always seek causation for an event. The real challenge for science is to separate “correlation” from “causation.”
Causation is just that — “the action of causing something,” while correlation simply means two events happening together. One example comes to mind. If you look at all patients with lung cancer, you will find that every patient had been drinking water. Water intake and lung cancer are correlated, but obviously water is not the causative factor in lung cancer.
Actually, when we compare our cholesterol levels to other countries, we find some interesting facts. America, despite its reputation, actually falls more in the middle of the pack. Other countries, (Norway to name one) have higher average cholesterol levels, but with lower levels of heart disease, so cholesterol cannot be “the final and only answer.”
Conclusion
In closing, statins play a role in the management of heart disease. What I want you to take home is that you should always be questioning the current trends, regardless of the many scientists/doctors who might be recommending them at this current moment – especially if it is a big business. This is not to say you should completely write off current trends, but you should seek to think things through in a logical fashion. Do your own digging to understand all sides. Don’t just go the way the tides may take you. This is where Internet has become such a useful tool.
I do know one thing, however: we still have a great deal to learn. Twenty years from now we will chuckle at how little we knew about heart disease, cholesterol, and statins in 2011.
