At the dawn of a new decade, what is the best way to assess a person’s risk for atherosclerosis? There are many tools to choose from but what is the optimal approach for someone who may have coronary artery disease?
First, have a physical examination and basic laboratory tests, including total cholesterol and LDL cholesterol. If the total cholesterol is over 200 or the LDL is over 100, enter the data into the American College of Cardiology risk calculator. This will give an estimate of the chance of heart attack or stroke within the next 10 years. Low risk patients 0-5% need no further testing or medication. High risk patients >20% should start on aspirin, blood pressure medication (if appropriate) and a statin. For borderline 5-7.5% and intermediate 7.5-20% categories, additional consideration is needed. You need to assess whether the patient has other risk enhancers. These include LDL > 160 mg/dl; high-sensitivity C reactive protein level > 2.0 mg/L; triglycerides > 175 mg/dl; peripheral arterial disease, chronic kidney disease, chronic inflammatory disease, metabolic syndrome, family history of premature heart disease, or premature menopause.
For the patient with borderline or intermediate risk and the presence of one or more risk enhancer, a statin should be initiated. If there is still uncertainty about starting medication or the patient is reluctant, do a coronary calcium score, obtained with a CT scan. Fortunately, locally, the cost for a coronary calcium score is just $99.
A coronary calcium score of 0 means there is no plaque in the heart arteries and the patient is at very low risk for a future heart attack. A calcium score 1-99 means there is plaque present and a statin should be considered. For those over 100, a statin is indicated, and further testing should be done to see if the plaque is causing significant blockage.
This approach is only for patients who do not have heart artery disease. For those with a history of disease or those who have diabetes with an LDL over 70, this approach should not be used, and those patients should be on a statin. This approach is only for adults between the ages of 40-75.
What about patients who are 75+? The risk for cardiovascular disease increases with age so taking a statin may help reduce that. On the other hand, other diseases also rise with age and limit the benefit of statins. For patients with a history of heart attack, stroke or cardiac revascularization, the data is clear: continue the statin. For primary prevention in those 75+, the data is less clear. A recent trial of patients over 70 showed a lower risk of dying from any cause for those on statin versus those who were not. Another study looked at patients 75+ who had their statin stopped. They were at higher risk for hospitalization and cardiovascular events. One reason for stopping a statin in older patients is the perception that statins increase the risk for dementia. However, a recent study of statin patients 70-90 years old confirmed that there was no increased risk for dementia. In fact, the statin patients showed less cognitive decline, suggesting statins may be protective for brain function.
So, if you are between 40 and 75 years old, see your doctor, have blood work, calculate your 10-year risk and see if a coronary calcium score is right for you. If you are over 75 years old, don’t stop the statin and discuss with your doctor the pros and cons of continuing medications.