How to Prevent Heart Disease

As you know, I love prevention of cardiovascular disease, and I love guidelines. I was very excited to see the release of the 2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease. What are these about? Primary prevention means preventing disease in people who don’t already have it. That means, if you have a known blockage in an artery in your heart, neck, or legs, or prior heart attack or stroke, these guidelines do not apply to you. If you already have one of those conditions and want to prevent future events, you are interested in secondary prevention.

These guidelines largely hash together information from previously published guidelines, such as the ones on cholesterol and hypertension. They present new recommendations regarding aspirin therapy, and also place greater emphasis on lifestyle modifications. Here’s what they say:

Patient-Centered Approach

The guidelines start by recommending a team-based approach to care and shared-decision making between patients and clinicians. What does this mean? It means you should utilize whatever health resources are available to you. This means not only your physician, but also nurses and nurse practitioners and physician assistants in your doctor’s office, as well as your pharmacist, and dietitians and health coaches if available. It also means you should ask questions and play a role in the plans for your health, whether it be medications or changes to exercise and diet.

Risk Assessment

An article on risk assessment was one of the first articles I posted on this website and it’s no surprise that it is addressed near the beginning of the guidelines. See my post here on the importance of risk assessment and how to do it. Many of the decisions we make in healthcare require an understanding of risk.

Nutrition and Diet

Heart disease decreased for many decades, until 2015 when heart disease deaths increased by 1%. This reversal is attributed to unhealthy diets.

The guidelines recommend a diet “emphasizing intake of vegetables, fruits, legumes, nuts, whole grains, and fish”. Evidence is cited favoring a “provegetarian” food pattern, meaning more vegetable consumption and less meat, egg, and dairy consumption. Consuming protein from plant sources is associated with lower rates of death than animal sources, with processed red meat carrying the highest risk.

The guidelines also recommend replacing saturated fats (cream, butter, lard) with unsaturated fats (vegetable oils). Trans fats, which carry the highest risk, are being phased out of the food supply in the United States.

Other specific foods to avoid include processed meats, refined carbohydrates, and sweetened beverages (including artificially-sweetened “diet” beverages).

Exercise

Both aerobic exercise and weight training have been shown to improve multiple aspects of health. They also improve mood, sleep, and energy levels.

The guidelines recommend 150 minutes/week of moderate-intensity exercise or 75 minutes/week of vigorous exercise.

Examples of moderate exercise include, brisk walking, ballroom dancing, and active yoga. Vigorous exercise includes jogging/running, singles tennis, or swimming laps. A general rule of thumb is – if you can carry a conversation but would find it difficult to sing, it is moderate exercise.

The guidelines also note that if you can’t meet the recommendations above, any exercise is better than none. Also, replacing sedentary behavior with even light activity may be beneficial. For example, it may be healthier to do light housework or go for a slow walk than it is to sit in a recliner and watch television (or write articles for a blog).

Obesity

As would be expected, the guidelines recommend weight loss in people who are overweight or obese. This can be attempted with comprehensive lifestyle programs with trained interventionists. Specific recommendations include exercising > 150 minutes/week, eventually increasing to 200-300 minutes/week to sustain weight loss. Additionally, calorie restriction by >500 calories/day from the initial diet should be attempted, usually resulting in a 1200-1500 cal/day diet in women and 1500-1800 cal/day in men. Waist circumference and BMI should be measured to assess obesity and results of interventions.

Type 2 Diabetes

Some of the recommendations for diabetes management are new in these guidelines. They of course recommend healthy diet and exercise. They also recommend first-line use of a medication called metformin to improve blood sugar control and decrease cardiac risk. This is not new. What is new is the recommendation for second-line therapy in patients with additional cardiac risk factors with two newer classes of medications, SGLT-2 inhibitors (gliflozins) and GLP-1R agonists (tides), which have also been shown to decrease cardiovascular risk.

High Blood Cholesterol

These recommendations mirror the cholesterol management guidelines which I have extensively discussed here. Also check out my post on cholesterol basics.

Hypertension

Once again, the document reinforces previously published guidelines which I discuss here.

Smoking Cessation

The benefits of quitting smoking on reducing cardiovascular risk are immediate. Your physician should discuss this with you and can also consider pharmacotherapy with nicotine replacement options. At this time, the guidelines note that it is unclear whether e-cigarettes are effective or safe as tools for tobacco cessation.

Aspirin

The recommendations regarding aspirin therapy in this document have received the most media coverage. Remember that these guidelines address primary prevention. If you have known vascular disease, these guidelines do not apply to you. In patients without previously diagnosed heart disease, the recommendations for aspirin therapy are updated in these guidelines.

The new recommendations are in part because recent studies have not shown as much of a benefit of aspirin in preventing cardiovascular events and death compared to older studies. Additionally, we have gotten better at controlling other risk factors, thereby resulting in a long-term decrease in cardiac disease, making any potential benefit of aspirin less. But the risk of bleeding from aspirin presumably is still the same.

Thus, the new guidelines recommend aspirin only among select individuals 40 to 70 years of age who are at higher ASCVD risk but not at increased bleeding risk. They do not specifically state what constitutes “higher ASCVD risk” but leave that as a decision for patient and clinician to make. For reference, the previous guidelines recommended aspirin for those with a 10-year risk > 10 percent, and the new guidelines are recommending less aggressive measures. They do mention patients with a strong family history and inability to achieve blood pressure and lipid goals as those who might potentially benefit. Presumably, continued tobacco use should also be considered as a factor.

If you and your physician do decide to use aspirin for the prevention of cardiovascular disease, the dose should be less than 100mg daily, usually 81mg (a “baby” aspirin) in the United States.

The guidelines also state that patients above the age of 70 should not receive aspirin on a routine basis. There is a higher risk of bleeding in this age group, but similarly to those aged 40 to 70 years, high risk features may lead a patient and physician to opt for aspirin as a preventative measure.

Reference: WRITING COMMITTEE MEMBERS, Arnett DK, Blumenthal RS, Albert MA, Michos ED, Buroker AB, Miedema MD, Goldberger ZD, Muñoz D, Hahn EJ, Smith Jr SC, Himmelfarb CD, Virani SS, Khera A, Williams Sr KA, Lloyd-Jones D, Yeboah J, McEvoy JW, Ziaeian B, ACC/ AHA TASK FORCE MEMBERS, O’Gara PT, Beckman JA, Levine GN, Chair IP, Al-Khatib SM, Hlatky MA, Birtcher KK, Ikonomidis J, Cigarroa JE, Joglar JA, Deswal A, Mauri L, Fleisher LA, Piano MR, Gentile F, Riegel B, Goldberger ZD, Wijeysundera DN, 2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease, Journal of the American College of Cardiology (2019), doi: https://doi.org/10.1016/j.jacc.2019.03.010.