A healthy lifestyle is a central recommendation for all patients in the ACC/AHA 2013 guideline. Many observational studies, such as the Nurses’ Health Study showing that women who followed a healthy lifestyle overall were 80% less likely to have a CV event compared to other women in the study (Stamfer et al, 2000), suggest that following a heart health diet is associated with lower CV events. The 2013 dietary and exercise recommendations are based on RCT evidence behind interventions that affect lipid and blood pressure control, not overall mortality or ASCVD events. In general, recommendations for lifestyle changes that reduce cholesterol are considered to be overall ‘heart healthy’, and benefit blood pressure as well.
| Case Three, revisited |
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| Nelson Nguyen is your 43 year old Vietnamese male patient living in Castro Valley, CA discussed on the previous page. He has poorly controlled hypertension, obesity, hyperlipidemia and smokes one pack a day of cigarettes. After calculating his cardiovascular risk to be 17%, you want to counsel him on healthy lifestyle changes to reduce his risk. |
Which one of the following statements about dietary changes would be the most accurate to use with the patient?
After you counsel Mr. Nguyen on treatment strategies, he tells you that he may not be able to return for care. He cannot afford to take time off from work because of his illness; he is the sole wage earner for his two children going to college, his wife, and his mother-in-law. Besides this, he has avoided medical attention for the past years for fear of a catastrophic diagnosis that would prevent him from supporting his family in the future. He says he can’t afford a gym, buy expensive “health” foods, and pay for expensive medications. How would you approach Mr. Nguyen?
| Evidence-based Heart Healthy Lifestyle Recommendations: ACC/AHA 2013 | ||
|---|---|---|
| Recommendation | Level of Evidence | Notes |
| Achieve and maintain a healthy weight | Not evaluated | This is a cornerstone of all lifestyle changes in 2013 ACC/AHA guidelines |
| DASH, USDA Food Pattern, or AHA diet. Follow a dietary pattern emphasizing intake of vegetables, fruits and whole grains; includes low-fat dairy products, poultry, fish, legumes, non-tropical vegetable oils and nuts; and limit intake of sweets, sugar-sweetened beverages and red meatsAdapt this pattern to personal and cultural food preferences, caloric requirements, and nutritional therapy for other conditions (e.g. diabetes) | A (strong) | DASH diet associated with 11 mg/dl drop in LDL level. Counseling pts to follow a Mediterranean diet has not been proven to affect cholesterol levels (but has been shown to lower BP slightly). The definition of ‘mediterranean diet’ differs between countries and studies. |
| Saturated fat 5-6% of calories
Reduce percent of calories from trans fat.
Aerobic activity: 3-4 sessions per week or moderate- to vigorous intensity activity, at least 40 minutes/session. |
A (strong)
A (strong)
B (moderate) |
In studies, this lowered LDL 11-13 mg/dl, 11% Exercise reduces LDL 3-6 mg/dL; no effect on HDL |
Note that reduction of dietary cholesterol intake is not recommended, due to a lack of evidence on dietary cholesterol’s effect on LDL level.
Intake of saturated fat is estimated to be 11% of all caloric intake in the US population – approximately twice as much as in the above heart-healthy recommendations. Diets that reduce saturated fat intake have been shown to reduce cholesterol levels by 11-13 mg/dl, or approximately 11%. Identify the top source of saturated fat in the US diet:
Alcohol, fitness level, tobacco use, and the addition of lifestyle to drug therapy are all potential considerations that may impact cholesterol and ASCVD, but were not included in the 2013 review due to time and space limitations. For example, dietary options you may observe being offered to statin-intolerant patients on your rotation may lower LDL but have unclear effect on health outcomes (CV events or mortality) include:
- Phytosterols, plant sterols
- Ground flax seed
- Dietary fiber
- Soy protein
- Psyllium (e.g. Metamucil)
Hypertriglyceridemia
There is a well-established link between hypertriglyceridemia and cardiovascular risk. However, there is debate as to whether triglycerides represent a biomarker for other processes, or are an independent risk factor. Over 30% of the US adult population has a triglyceride level over 150 mg/dl (Volnada 2012), and most of this elevation is related to lifestyle. Although not specifically addressed in the 2013 guidelines, a brief overview is presented here to assist with patient counseling.
| Classification of Serum Triglycerides (mg/dL; fasting) |
|---|
| <150 Normal 150-199 Borderline High 200-499 High ≥ 500 Very High |
Key points in hypertriglyceridemia:
- In all patients, triglyceride levels are modified by body habitus, activity level, and dietary factors like simple carbohydrate (including sugars and fructose) and trans-fat consumption. Click here to see a list of common high-fructose containing foods.
- In additional to genetic disorders not reviewed here, frequent causes for very high hypertriglyceridemia include excessive alcohol intake, uncontrolled diabetes, and hyperalbuminuria (Vonalda 2012).
- Patients with hypertriglyceride levels ≥ 500 mg/dL should be evaluated for other causes.
- At triglyceride levels of approximately 1000 mg/dl or higher, the risk for pancreatitis rises. However, only 20% of patients with levels this high will actually develop pancreatitis. The risk of retinal thrombosis is much smaller.
| Effects of Nutrition Practices on Triglyceride Lowering | |
|---|---|
| Nutrition Practice | TG-Lowering Response, % |
| Weight loss (5% to 10% of body weight) | 20 |
| Implement a Mediterranean-style diet vs. a low-fat diet | 10-15 |
| Add marine-derived PUFA (EPA/DHA) (per gram) | 5-10* |
| Decrease carbohydrates 1% Energy replacement with MUFA/PUFA |
1-2 |
| Eliminate trans fats 1% Energy replacement with MUFA/PUFA |
1 |
| TG indicates triglyceride; PUFA, polyunsaturated fatty acid; EPA, icosapentaenoic acid; DHA, docosahexaenoic acid; and MUFA, monounsaturated fatty acid (Miller, 2011)* Intake of omega-3 fatty acids has not been definitively shown to reduce CV events in patients with hypertriglyceridemia.
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A practical one-page summary for management of all levels of hypertriglyceridemia from the American Heart Association can be found here.
The physician’s role in lifestyle change
A minority of the U.S. population follows a heart-healthy dietary pattern. Change requires true commitment from the patient; simply recommending to your patient to adopt these lifestyle changes is unlikely to affect their behavior. Facilitating sustained behavior change through engagement and effective counseling is a critical part of the physicians’ job. To enhance your clinical effectiveness and practice motivational interviewing techniques, visit the Kaiser Foundation’s interactive module on Management of Chronic Conditions to practice on a patient with CAD and hyperlipidemia (enter your name, email, and choose the CAD module).
Share this patient-friendly American Heart Association site with English-speaking patients on healthy diets.
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