How effective are statins in preventing heart disease and stroke?

Joseph Saseen, PharmD
Cholesterol Management
Statins are proven in multiple clinical trials to reduce the risk of a cardiovascular disease event (e.g., heart attack, stroke).
Kent Holtorf, MD
Endocrinology Diabetes & Metabolism
Statin drugs are used to lower cholesterol levels and are the most prescribed (and marketed) medications in the US. They have been highly touted as an effective means to prevent heart attacks and strokes. A recent major trial reported that patients with normal cholesterol levels but increased inflammation had a small but significant reduction in "cardiovascular events" when placed on the statin Crestor compared to placebo.

Statins were initially approved by the Food and Drug Administration (FDA) for the prevention of a repeated heart attack or stroke in patients with high cholesterol who had already suffered from a heart attack, which is called "secondary prevention." Physicians and the public then came to believe that statins could prevent heart attacks in individuals without heart disease but who have elevated cholesterol levels, which is known as "primary prevention." This has resulted in the majority of people who use statins to be doing so for primary prevention of heart attacks and strokes. This has, of course, been continuously reinforced by massive drug company marketing to both doctors and the public to support the 25 billion per year in sales that these medications bring.

It is coming to light that the benefits of using a statin for primary prevention have been greatly exaggerated and have not been shown to be beneficial when compared to placebo. Evidence keeps mounting that using a statin to lower cholesterol in someone without known heart disease is of little if any benefit. In recent years, fourteen major studies found no cardiovascular protection with statin use in those without known heart disease or were halted because no benefit was shown. A review study published in the Annals of Internal Medicine analyzed the evidence of statin use for primary prevention. Data was available for over 65,000 high risk patients who were treated with statins to lower cholesterol for primary prevention. The study found no benefit to treatment.
There is limited evidence that statins help prevent a first heart attack and are cost-effective and improve patient quality of life. Statins may also relatively reduce the risk of a first stroke, but again, the evidence is limited. The decision to start statins or not should depend on a person's cardiovascular risk factors and lipid/cholesterol levels. You can discuss this with your doctor.
Spencer D. Kroll, MD
Internal Medicine
The modern age of lipidology started with the publication of the landmark 4S trial in 1994, showing that lowering of LDL with statins significantly reduced heart attack recurrence. It was from this study that the association between cholesterol reduction by statins and the inhibition of cardiovascular events was proven. After this, pharmaceutical companies were encouraged to develop more potent statins that have allowed physicians to achieve even greater LDL cholesterol reductions. We now live in at a time where there are successive trials that demonstrate the effectiveness of lower and lower LDL targets for preventing heart disease. The decreased incidence of fatal heart attacks as a result of statin discovery and use may be one of the greatest discoveries of the modern age. Still, controversies continue as to when and if to use statins, particularly in primary prevention. It is thus very important to define patients who might be at medium or intermediate risk. LDL targets are just one measure.

As to the controversy about statin use in primary prevention, according to a recently published meta-analysis of persons at low risk for vascular disease (including those receiving statins for primary prevention), statins reduced the risk of major vascular events by 21% per each reduction of 1.0 mmol per liter (38.7 mg per deciliter) in low-density lipoprotein cholesterol. The risk of death from vascular causes was reduced by 12%. There was no increase in the incidence of cancer or the rate of cancer-related death. Even among participants with estimated 5-year event rates of less than 5%, there was a 38% reduction in the rate of major vascular events, a 43% reduction in the rate of major coronary events, and a 48% reduction in the rate of revascularization.  

Given the immense threat of a growing cardiovascular risk burden, it is very important to determine a patient's risk and treat appropriately. But if there is criticism that statins are overused in primary prevention, it is because too many clinicians jump to treatment for simply "bad numbers."  The initial benefits of primary prevention that were surmised from the WOSCOPS and AFCAPS/TexCAPS trials showing reductions in MI and other coronary events have been tempered by subsequent meta-analysis. But this does not diminish the important role of statins in primary prevention in appropraiately selected patients.  

Continue Learning about Heart and Circulatory System

Be Apprehensive About Heart Health Apps
Be Apprehensive About Heart Health Apps
We know you wouldn’t buy the Brooklyn Bridge—although many folks have believed they did! Around 1900 con man, George C. Parker sold it over and over (...
Read More
How is cholesterol related to coronary artery disease?
Intermountain Registered DietitiansIntermountain Registered Dietitians
Cholesterol is a substance that carries digested fat from your liver to other parts of your body. Ab...
More Answers
When is stereotactic radiosurgery recommended for AVMs in the brain?
Dr. Geoffrey P. Colby, MDDr. Geoffrey P. Colby, MD
Stereotactic radiosurgery is used on arteriovenous malformations (AVMs) in the brain that have an ac...
More Answers
What Are the Risks Associated with Lvads?
What Are the Risks Associated with Lvads?

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.