Cholesterol management is an important aspect of prevention of heart disease. Primary prevention for individuals without cardiovascular disease includes lifestyle modifications including dietary restrictions and physical activity, and medical therapy primarily with a statin. Since primary prevention involves treating healthy individuals, deciding to initiate statin therapy has been a controversial issue.
In 2018, the American Heart Association (AHA) along with the American College of Cardiology (ACC) updated guidance for management of blood cholesterol. At face value, the updated AHA/ACC guideline for management of blood cholesterol may appear to drastically change the conversation about statin therapy for primary prevention of cardiovascular disease. However, the data hasn’t changed as fast as its interpretation.
The new AHA guidelines recommend testing blood cholesterol at a younger age with more frequent intervals for repeat testing. While time in the exam room is limited, be sure to discuss the clinical uncertainties before checking the box.
The new AHA guidelines recommend testing blood cholesterol at a younger age with more frequent intervals for repeat testing. While time in the exam room is limited, be sure to discuss the clinical uncertainties before checking the box.
Here are ten points about cholesterol management to discuss with your patients.
- Before ordering a lipid panel, discuss what you will do with the information. If you typically plug the numbers into a calculator, keep in mind that risk stratification using computer modeling tools like the AHA’s pooled cohort equation overestimate cardiovascular disease risk among all patients, particularly when patients are prescribed modern medical therapies (DeFilippis et al 2017).
- Statin therapy lowers the risk of cardiovascular events in patients with 10-year atherosclerotic cardiovascular disease (ASCVD) risk of 7.5% (NNT= 108 after 5 years of therapy). For patients with a ≥ 10% ten-year ASCVD risk, statins may also reduce death.
- Statin therapy isn’t risk-free. Up to 30% of patients experience muscle aches and up to 50% discontinue therapy for a variety of reasons ranging from myalgia to abnormal liver function testing (Zhang et al 2013). Statins may increase the risk of developing type 2 diabetes in some patients.
- Biomarkers such as C-reactive protein and lipoprotein(a) have not been found to improve cardiovascular risk stratification or outcomes. Even so, evaluation of these ‘risk enhancers’ is currently recommended by the AHA for patients at borderline-risk (estimated 10-year ASCVD risk of 5-7.4%).
- Considering non-traditional risk factors such as family history of cardiovascular disease can help personalize the discussion about testing and treatment with patients, especially those at borderline risk.
- Frequent monitoring of low-density lipoprotein (LDL) may help determine if patients are adherent to therapy. Increasing dosage or adding additional LDL-lowering agents (such as niacin or ezetimibe) will reduce LDL without improving clinical outcomes.
- Coronary artery calcium scoring may allow some patients to forgo statin therapy if they manage to score zero. However, many more patients will fall into the ‘gray zone’ with a score between 1 and 99, which usually triggers initiation of a statin. Coronary artery calcium scoring will not help risk stratify smokers or those with a strong family history of cardiovascular disease.
- The benefits of ezetimibe therapy for primary prevention of cardiovascular disease is unknown. The only clinical trial demonstrating benefit compared ezetimibe plus statin therapy to placebo alone. There is no evidence demonstrating that ezetimibe plus statin therapy is any better than statin therapy alone for improvement of patient-oriented outcomes.
- Adults over age 75 without diabetes or known cardiovascular disease are unlikely to benefit from statin therapy for primary prevention. Consider de-escalating therapy in these patients.
- There is limited evidence to support statin therapy for primary prevention among adults in their thirties and no evidence among adults in their twenties. Statin therapy is contraindicated in pregnancy--- an important consideration for women in these age groups.
The new AHA/ACC guidelines recommend initiating testing blood cholesterol at a younger age with more frequent intervals for repeat testing. It may be tempting to reflexively begin ordering this test for many patients. While time in the exam room is limited, be sure to discuss the clinical uncertainties before checking the box. This discussion represents an opportunity to learn more about your patients while engaging in shared decision-making for this complex topic.