Understanding The New Cholesterol Guidelines

The new cholesterol guidelines are here! This is a big deal for a heart disease prevention nerd such as myself because blood cholesterol is one of the primary drivers of heart attacks and strokes. If you haven’t already, take a look at my post on cholesterol basics for a better understanding of blood cholesterol, and then come back here to see what the new guidelines mean for you. The guidelines are published by the American College of Cardiology, the American Heart Association, and a number of other medical organizations.

What are guidelines? These are large, thorough documents that are published intermittently by prominent medical organizations. They are put together by really smart, really experienced people – physicians and other professionals who are leaders in their fields. They are well-referenced with data from studies that support their recommendations. That being said, there is a common phrase in medicine – “guidelines are just that … guidelines” – meaning that they aren’t rules or laws that need to be followed. Every patient is different, and sometimes an alternative approach is required. Also, guidelines are updated every few years or even less often, so frequently they are out-of-date. So, guidelines aren’t perfect, but they are great resources because of the expertise and thought that goes into them.

What do the cholesterol guidelines say?

The new cholesterol guidelines replace the last set that was published in 2013. They are largely the same, but there are a few very interesting developments.

The guidelines only devote one page (out of 69) to healthy lifestyle recommendations, and instead of a thorough treatment, refer to an older guideline on lifestyle management. However, the first recommendation in their list of “Top 10 Take-Home Messages” is to emphasize a heart healthy lifestyle. Stay tuned to this blog for frequent posts on exercise, nutrition, and weight loss so that you too can live a heart healthy lifestyle!

Should you be on a statin medication?

The guidelines mostly address the use of statin medications to treat cholesterol, primarily because statins are one of the most effective tools we have for the prevention of cardiac events. According to the guidelines, there are four major groups of patients aged 20-75 who are likely to benefit from a statin. Follow this algorithm to see if you belong to one of those groups:

1. Do you have known atherosclerotic cardiovascular disease (ASCVD)?

This includes diagnoses such as prior heart attack, coronary intervention (stent, angioplasty, or bypass surgery), stroke, TIA (mini-stroke), or peripheral vascular disease.

This is obviously a high risk group and the guidelines recommend high-intensity statin therapy, with the addition of other medications, such as ezetimibe or PCSK9 inhibitors, in select very-high risk individuals.

2. Do you have LDL-cholesterol (LDL-C) > = 190 mg/dL?

LDL levels this high are strongly associated with the development of cardiovascular disease, and the guidelines recommend high-intensity statin therapy, even at a relatively young age. Levels this high are also suggestive of a genetic condition called Familial Hypercholesterolemia, and family members should be screened by having lipid profiles checked.

3. Do you have diabetes?

Diabetes is one of the strongest risk factors for cardiovascular disease. The guidelines recommend moderate-intensity statin therapy in patients aged over 40, and high-intensity therapy if other risk factors are present. Statins should be considered in younger patients if certain risk factors are present.

4. Are you aged 40-75 with a calculated ASCVD risk > 5%?

Most statin eligible patients fall into this group, and to identify whether you are one of those people, you need to know your risk. If you don’t know it yet, see our article on cardiac risk to gain a better understanding of what cardiac risk is and calculate your own risk!

ASCVD risk > 20%

Patients with a risk score >= 20% are deemed high-risk, and high-intensity statin therapy is recommended.

ASCVD risk between 7.5% and 20%

The biggest change to the guidelines is the recommendation for a discussion of risk between patient and physician for this group of people. This discussion should include the calculated level of risk (a risk of 8% is far different than a risk of 19%) as well as consideration of certain “risk-enhancing” factors. These factors are listed below.

The guidelines seem to imply that most patients in this group would benefit from at least moderate-intensity statin therapy. They suggest that if the decision is uncertain after discussion, a coronary calcium score may help guide the process. Specifically, older patients without many risk factors are a very diverse population in terms of cardiac risk, and a coronary artery calcium scoring may help guide the decision about statins.

Personally, I would take a statin if I fell into this category, based on the reduction in cardiovascular events and the fact that statins are overwhelmingly safe and also generally well tolerated. However, if you are unsure, the guidelines recommend getting a coronary calcium score to help you and your physician make a decision.

ASCVD risk between 5 and 7.5%

People who fall into this category are termed “borderline risk”. Under the old guidelines, statins were recommended for this group, but the new guidelines recommend a risk discussion and consideration of statin therapy if “risk enhancers” are present. These risk enhancers are listed below. The guidelines suggest that this group of patients may also benefit from coronary artery calcium scoring to further define risk level.

Risk enhancers

• Family history of premature cardiovascular disease
• LDL-C greater than 160 or non-HDL-C greater than 190
• Metabolic syndrome
• Chronic kidney disease
• Inflammatory conditions (such as psoriasis, rheumatoid arthritis, HIV/AIDS)
• Premature menopause
• History of gestational risk factors such as pre-eclampsia or gestational diabetes
• South Asian ancestry
• Persistently elevated triglycerides > 175
• If measured:
  • Elevated high sensitivity CRP (> 2.0 mg/L)
  • Elevated Lp(a) (> 50 mg/dL or > 125 nmol/L)
  • Elevated apoB (>130 mg/dL)
  • ABI < 0.9

Other known risk enhancers that are not mentioned in the guidelines:

• Erectile dysfunction
• Elevated uric acid/gout
• Secondhand smoke exposure

Don’t fall into one of the above groups?

Age > 75

Age is one of the most powerful risk factors for cardiovascular disease. In this age group, if your LDL is greater than 70, a moderate-intensity statin should be considered to decrease risk, especially if you are very functional and have a reasonable life expectancy. A coronary calcium score of zero may be helpful in identifying patients who would not benefit from statin therapy.

Age 20-39

Although cardiac events are uncommon in this age group, the development of arterial disease begins at a young age and the burden of risk factors over time increases risk later in life. Lifestyle modifications are of tremendous importance in this age group, but statins should also be considered if LDL-C is greater than 160 and there is a family history of premature cardiovascular disease.

ASCVD risk < 5%

The guidelines refer to these patients as low risk, but I would prefer the term “normal-risk”. Even though the 10-year risk may not be very high, the lifetime risk of having a heart attack or stroke may be quite elevated, especially in younger people. If you have risk factors, or even if you don’t, this is a great time to start living a healthy lifestyle through good nutrition and exercise!

Summary

The new guidelines are here. Most importantly, they stress the importance of lifestyle modifications for the prevention of cardiovascular disease. They also recommend statin medications for adults with known cardiovascular disease, those with LDL-C > 190, and diabetics aged 40-75 with LDL-C > 70. If you are over the age of 40 and do not fall into one of those groups, you should calculate your 10-year risk, and discuss a statin with your physician based on that risk and the presence of other risk-enhancers.

Reference: Grundy SM, Stone NJ, Bailey AL, Beam C, Birtcher KK, Blumenthal RS, Braun LT, de Ferranti S, Faiella-Tommasino J, Forman DE, Goldberg R, Heidenreich PA, Hlatky MA, Jones DW, Lloyd-Jones D, Lopez-Pajares N, Ndumele CE, Orringer CE, Peralta CA, Saseen JJ, Smith SC Jr, Sperling L, Virani SS, Yeboah J. 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/AphA/ASPC/NLA/PCNA guideline on the management of blood cholesterol: a report of the American College of CArdiology/American Heart Association Task force on Clinical Practice Guidelines. Circulation. 2018