The American Heart Association (AHA) and American College of Cardiology (ACC) recently released an update to the 2013 cholesterol guidelines, calling for more personalized risk assessments to guide primary and secondary cardiovascular disease prevention throughout a patient's lifetime.
"Both guidelines were very much based on the evidence that has developed in terms of what can benefit patients," said Neil Stone, MD, MACP, FAHA, FACC, who worked on the 2018 guideline update and served as vice chair of the writing committee. Stone, a Chicago-based cardiologist and AHA national spokesperson added, "Both begin with emphasizing that lifestyle change is most important."
In fact, he continued, the new guidelines focus on adopting a heart-healthy lifestyle from a young age and build upon the 2013 emphasis on identifying and addressing lifetime risks to prevent cardiovascular disease (CVD). The update also provides additional guidance for physicians to help them drill down for a more robust and personalized risk assessment that considers multiple factors and treatment paths.
The need for personalized risk stratification and intervention is great in the United States. Stone pointed out we live in a country where one of every three people dies of heart disease or stroke annually and nearly six in 10 people develop heart disease during their lifetime. Additionally, he said, one-third of American adults have high levels of low-density lipoprotein cholesterol (LDL-C), known as the 'bad' cholesterol that contributes to plaque buildup and narrowed arteries.
Key highlights from the updated cholesterol clinical practice guidelines statement, which was released this past November during the AHA's 2018 Scientific Sessions conference in Chicago, include:
- High cholesterol, at any age, can increase a person's lifetime risk for heart disease and stroke. A healthy lifestyle is the first step in prevention and treatment to lower that risk.
- The 2018 guidelines recommend more detailed risk assessments, called risk enhancing factors, to help healthcare providers better determine a person's individualized risk and treatment options.
- In some cases, a coronary artery calcium score can help determine a person's need for cholesterol-lowering treatment, if their risk status is uncertain or if the treatment decision isn't clear.
- While statins are still the first choice of medication for lowering cholesterol, new drug options are available for people who have already had a heart attack or stroke and are at highest risk of having another. For those people, medication should be prescribed in a stepped approach, first with a maximum intensity statin treatment, adding ezetimibe if desired LDL cholesterol levels aren't met and then adding a PCSK9 inhibitor if further cholesterol reduction is needed.
Stone, who is a professor of medicine at Northwestern University's Feinberg School of Medicine and the medical director of the Vascular Center of the Bluhm Cardiovascular Institute of Northwestern Memorial Hospital, noted that for those trying to prevent a first heart attack or stroke, personalized risk stratification informs next steps for primary prevention. For those trying to prevent another heart attack or stroke, the guidelines provide additional treatment options for those at very high risk.
For those who have not yet had a heart attack or stroke, Stone said the updated guidelines call for patients with a very high LDL - 190 or more - to be on a high intensity statin. For those with diabetes between the ages of 40 and 75, no matter what the LDL number, the updated guidelines continue the 2013 recommendation for them to be on a statin, as well. He added, "Those who have long-standing diabetes or are older than 50 may do better on a higher intensity of statin."
The new guidelines call for a more nuanced approach to statin use in the largest group - those 40 to 75 without diabetes or the highest LDL-C. Stone said by virtue of four different clinical trials assessing 10-year risk, individuals with a score of 7.5-19.9 percent should at least be considered for statin therapy. He added, those with a score of 5 percent or less typically don't need statins, and those with a score of 20 percent or higher on the risk calculator should automatically be on statin therapy.
"The previous guidelines recommended a clinician-patient risk discussion before a statin was given," he said of the borderline group. "The new guidelines also recommend a clinician-patient discussion, but they give more details of what that should be. The idea is to provide a way for doctors to give patients, who aren't sure whether to take a statin, factors to show a patient what their personal risks are."
In addition to traditional risk factors like smoking and high blood pressure, the new guidelines outline a number of other risk-enhancing factors to consider, including: family history and ethnicity, LDL ³ 160, triglycerides persistently above 175, premature menopause or pre-eclampsia, chronic inflammatory conditions such as rheumatoid arthritis, metabolic syndrome, and chronic kidney disease.
A coronary artery calcium (CAC) score can also help tip the scale on whether or not to start statin treatment immediately. A CAC of zero has typically indicated a low risk of CVD, which has been borne out by two large-scale studies. "We are not recommending calcium scores as a screening test," Stone stressed. "We're using it as a tie-breaker ... it can be the decider," he added.
"Someone with a (risk assessment) score of 9 percent, few other risk factors, and a coronary calcium score of zero may wish to postpone statin use for five to 10 years because their risk is relatively low," Stone continued of using the personalized approach at the heart of the new guidelines.
For everyone, no matter where their risk assessment percentage falls, he stressed the importance of lifestyle modification to either delay or prevent the need for statins or to enhance the work of statins in maintaining heart health. "We point out even if you're on a statin, you need to focus on lifestyle because the lower you can get your number on a statin, the lower your risk," stated Stone.
For individuals who have already suffered a heart attack or stroke, the new guidelines call for additional intervention when LDL-C is not well controlled. "We have three trials showing if the LDL is above 70 in people who are very high risk, they might benefit from not just a maximally tolerated statin but also the non-statin ezetimibe or PCSK9 injection or shot," explained Stone.
He added the recommendation is for a stepwise approach. Stone said the addition of ezetimibe would get a significant portion of high-risk patients under the 70 LDL benchmark. Available as a generic, ezetimibe is typically affordable and well tolerated by patients.
For those who cannot achieve the desired goals with a combination of statin and ezetimibe, a PCSK9 inhibitor could be added. The new guidelines also note a PCSK9 inhibitor might be added as a primary prevention tool for individuals who have a genetic condition that causes high LDL-C.
However, Stone noted, the shot is considerably more expensive. Some insurers have been slow to cover the treatment, although there has been movement in recent months to lower the cost. The AHA and ACC are bringing together stakeholders to further discuss financial barriers to achieving optimal primary and secondary prevention of heart disease and stroke.
Once treatment has started, whether lifestyle modification only or modification with medication, physicians should schedule a follow-up appointment within four to 12 weeks to assess adherence and effectiveness with a fasting lipid test. The guidelines then call for retesting every three to 12 months, depending on determined needs.
Stone said the new guidelines recognize and address the cumulative effects of high cholesterol over a lifetime. In most children, an initial test could be administered between the ages of 9 and 11. For some children with a strong family history of heart disease and high cholesterol, selective cholesterol testing might be appropriate as young as age two. While most children won't need medication, physicians should use the test to discuss the positive impact healthy behaviors have on lifetime CVD risk.
The updated guidelines offer a more individualized method to controlling cholesterol. "Before, it wasn't a one-size-fits-all approach, but everybody thought if you had a score of 7.5 percent or more, you automatically go on statin therapy. The new guidelines really make it clear how to use enhancers to personalize the risk discussion," Stone concluded.
2018 Guideline Update in Circulation
AHA/ACC Special Report: Use of Risk Assessment Tools to Guide Decision-Making in Primary Prevention of Atherosclerotic CVD