Statins are widely used to help prevent heart attacks, but a new study shows that the same process that causes this class of drugs to reduce heart attack risk can also increase memory loss, muscle problems, joint pains and diabetes (American Journal of Physiology – Cell Physiology, July 29, 2015).
Progression to a Heart Attack
Susceptibility to heart attacks starts many years beforehand when plaques start to form in arteries. First your immunity punches holes in the inner linings of your arteries (see my report below on inflammation). Then immune cells called macrophages bring fat (cholesterol) into the damaged arteries.
They also attract other macrophages to help form plaques along the inner blood vessel walls. For many years, macrophages can continue to attack the plaques that they have helped to form. They release enzymes that weaken the fibrous cap that separates the plaque on the inner lining of the artery from the flow of blood.
A heart attack occurs when:
- a plaque breaks off from the inner lining of an artery that carries blood to the heart,
- the plaque travels down that ever-narrowing artery until it blocks the flow of blood to the heart muscle completely,
- the part of the heart muscle supplied by the blocked artery then suffers from lack of oxygen, hurts and then dies,
- then the heart can start to beat irregularly or it can stop beating completely, and
- the damaged heart muscle can heal and be replaced by scar tissue, or * the damaged heart can start to beat irregularly or it can stop beating completely and the patient can die.
Why Statins Reduce Heart Attack Risk
Statins help to prevent plaques from forming in arteries by blocking the liver’s production of cholesterol that forms plaques
Statins also block the production of macrophages that secrete enzymes that can break off the plaques to cause heart attacks.
New Study Shows How Statins Can Harm
The blocking of macrophages that makes statins useful for heart attack prevention can also lead to memory loss, muscle pain, osteoarthritis and diabetes. Macrophages develop from stem cells inside the bone marrow and inside special tissue called mesenchyma throughout the body. Bone marrow stem cells mainly become blood cells, but mesenchymal stem cells develop into all cell types, including bone, cartilage, muscle and macrophages.
This study showed that statins work by preventing stem cells from turning into macrophages. Thus statins prevent heart attacks by decreasing inflammation and improving plaque stability in patients with heart disease, but statins also prevent stem cells from growing and differentiating into new adult body cells to cause:
- Muscle pain: statins interfere with muscle repair, particularly after intense exercise
- Memory Loss: Statins reduce your ability to grow new nerve cells to replace worn out and damaged nerve cells
- Osteoarthritis: Statins reduce your ability to grow new cartilage
- Diabetes: Statins increase diabetes risk by raising blood sugar levels. When you eat a meal that contains carbohydrates, they are converted to simple sugars. Some of the excess sugars go to your liver, where they are converted to triglycerides and cholesterol. However, statins prevent your liver from making cholesterol, so the excess sugar that is not converted to cholesterol goes back from the liver into your bloodstream to raise blood sugar levels. Statins also block the action of insulin to raise blood insulin levels.
- Statins also have been shown to increase stem cell aging and reduce your ability to repair damaged genetic material called DNA.
If you are at high risk for a heart attack, there is abundant data that you can benefit from taking statins. However, if you are at low risk for a heart attack, you should discuss both the benefits AND RISKS of taking statins with your doctor before making your decision.
Gabe Mirkin, M.D., is a sports medicine doctor and fitness guru. A practicing physician for more than 50 years and a radio talk show host for 25 years, Dr. Mirkin has run more than 40 marathons and is now a serious tandem bike rider with his wife, Diana. His website is http://drmirkin.com/. Click to read Gabe’s full bio.