Nonpharmacologic Treatment of Dyslipidemia ⁎ Mark C
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Progress in Cardiovascular Disease 52 (2009) 61–94 www.progcardvascdis.com Nonpharmacologic Treatment of Dyslipidemia ⁎ Mark C. Houston , Sergio Fazio, Floyd H. Chilton, Dan E. Wise, Kathryn B. Jones, Thomas A. Barringer, Dean A. Bramlet Vanderbilt University School of Medicine, Nashville, TN Wake Forest University Health Sciences, Winston-Salem, NC Presbyterian Center for Preventive Cardiology, Charlotte, NC University of North Carolina School of Medicine, Chapel Hill, NC Duke University School of Medicine, Durham, NC Cardiovascular disease is the number one cause of preference for natural or alternative therapies. A more morbidity and mortality in the United States,1 with aggressive integrative approach to the management of coronary heart disease (CHD) and myocardial infarction dyslipidemia is recommended to improve CHD outcomes, (MI) being the leading causes of death.1 The 5 major risk minimize adverse effects, and reduce health care costs. factors for CHD—hypertension, dyslipidemia, diabetes Pharmacologic therapies for dyslipidemia have been mellitus, smoking and obesity1,2—account for 80% of the discussed in detail in many recent reviews and will not risk for CHD. Interventions, both pharmacologic and be discussed in this article. nonpharmacologic, can improve all of these risk factors and decrease the incidence of cardiovascular disease (CVD) and its consequences such as MI, angina, Part I: Nutrition and Exercise congestive heart failure, and stroke.3-6 In this article, we Introduction will review the nonpharmacologic treatment of dyslipide- mia. Recent guidelines by the National Cholesterol Optimal nutrition and proper aerobic and resistance Education Program recommend more aggressive control exercise form the cornerstone for the management of of serum lipids to reduce the incidence of CHD.7 dyslipidemia. Changes in weight and body composition Nutritional and dietary therapy, weight loss, exercise, with loss of total body and visceral fat can have dramatic and scientifically proven nutritional supplementation changes in serum lipid levels that are similar to many should be used initially in appropriately selected patients pharmacologic therapies. In this section we will discuss to manage dyslipidemia. Hypertriglyceridemia, frequently the numerous modalities that have been studied in the due to obesity, insulin resistance, metabolic syndrome, literature that can provide an effective initial treatment and diabetes mellitus,7 deserves special attention. Phar- plan for improvement in serum lipid levels. macologic therapy should be administered in those cases that are at high or very high risk for CHD or who do not Nutrition respond to nondrug therapy. Many patients prefer nondrug therapies for many reasons including adverse effects of Multiple approaches to diet therapy have been initiated antilipid drugs, contraindications or allergic reactions to for improvement of hyperlipidemia and reduction of CVD. drugs, perceptions of adverse effects of drugs, or personal Dietary approaches extend from one extreme to another regarding fats, sugar, and protein content. Ornish8 investigated 48 individuals with moderate to severe CVD established by quantitative angiography in a Statement of Conflict of Interest: see page 84. ⁎ Address reprint requests to Mark C. Houston, MD, MS, 4230 randomized trial. Su\bjects were randomized to usual Harding Road, Suite 400, Nashville, TN 37205. care or intensive therapy. The intensive therapy group E-mail address: [email protected] (M.C. Houston). consisted of a diet with 10% fat, 10 mg cholesterol daily 0033-0620/$ – see front matter © 2009 Elsevier Inc. All rights reserved. doi:10.1016/j.pcad.2009.02.002 62 M.C. Houston et al. / Progress in Cardiovascular Disease 52 (2009) 61–94 (plant based) associated with moderate aerobic exercise, provided to both groups. In the patient population, 76% stress management training, smoking cessation, and group completed the study in the LCKD group, as opposed to the psychosocial support. Of 28 individuals in the intensive LFD group where only 57% completed the study. In 24 therapy group, 20 completed the trial, and 15 of 20 people weeks, there was greater weight loss in the LCKD group in the control group completed the 5-year trial. The than in the low-fat group (12.9% vs 6.7%). The LCKD intervention group had a decrease in the diameter of group had greater decrease in triglyceride levels (74.2 mg/ coronary stenosis of 1.75 absolute percentage points at 1 dL vs 27.9 mg/dL). High-density lipoprotein increased in year and 3.1 after 5 years. In contrast, the percent diameter the LCKD group compared with the low-fat group (5.5 vs in the control group increased by 2.3 percentage points in 1.6 mg/dL). Low-density lipoprotein cholesterol (LDL-C) 1 year and 11.8 percentage points in 5 years. Even with did not change significantly.11 this small cohort, these were statistically significant. In a More detailed information concerning CV risk reduc- subsequent trial using the Ornish approach, 440 men and tion can be obtained by evaluating lipoprotein subclass women with coronary disease and diabetes mellitus (DM) analysis. Studies have suggested that LDL particle were evaluated for compliance to comprehensive lifestyle concentration and HDL particle concentration are more therapy for a 1-year duration. There were 347 men (55 predictive in assessing CV risk.12 with DM) and 93 women (33 with DM). Adherence to the There is discordance between LDL-C or even non– lifestyle demonstrated weight reduction of 5 kg, body fat HDL-C and LDL particle concentration (LDL-P). This is reduction, low-density lipoprotein (LDL) reduction, most pronounced in patients with type 2 DM, metabolic functional capacity improvement and improvement in syndrome, or familial combined hyperlipidemia. In quality of life indices. No significant changes were noted numerous studies,13-15 nuclear magnetic resonance in high-density lipoprotein (HDL) or triglycerides. Within (NMR) technology has been used and demonstrated the diabetic cohort, 20% of the patients had a decrease in superior predictive power in assessing CV risk. Nuclear the amount of diabetic medication required to control their magnetic resonance used the unique signal generated by blood glucose. The intensive intervention group produced each lipoprotein to identify the type of particle (LDL, improvement in weight, body fat, and LDL. There was not HDL, very low-density lipoprotein [VLDL]). The apo- a significant change in HDL and triglycerides.9 protein components of each particle are unique and Overweight patients with type 2 DM present a difficult constant allowing the number of particles to be measured. challenge to reduce their cardiovascular (CV) risk factors. The amount of triglyceride (TG) and cholesterol contained The Look AHEAD trial had 5145 individuals with type 2 in each particle can vary significantly, leading to the DM with a body mass index greater than 25. Intensive discrepancy between estimates of risk assessed by LDL-C lifestyle intervention with group and individual meetings and LDL-P. There can be as great as a 70% difference in were designed to achieve and maintain weight loss by particle concentration when the amount of cholesterol and decreasing energy intake and increasing physical activity. TG per particle is constant, but there is a change in particle The control group included diabetes support and education size. At the same particle size, the concentration of TG and only. The lifestyle intervention group was designed to cholesterol can vary leading to as much as a 40% induce a minimum weight loss of 7% from initial body difference of LDL-P at the same LDL-C. weight by energy restriction primarily and exercise. The Westman et al16 evaluated the effects of the LCKD vs maximum energy uptake from fat was 30%, saturated fat LFD on NMR lipoprotein subclass analysis. Using 10% and the minimum from protein was 15%. Participants standard analytic measures of lipid, there was a decrease were prescribed portion-controlled diets using liquid meal in TG in both groups but significantly greater in the LCKD replacements and frozen entrees. The exercise program group. High-density lipoprotein increased significantly in was graduated to a goal of 175 minutes of moderate the LCKD group but not the LFD group. Low-density activity weekly. The 1-year data revealed the intensive lipoprotein did not change significantly in either group. lifestyle group lost an average of 8.6% of their total body Both diets had a positive effect on lipoprotein subclasses weight vs 0.7% in the control group. Mean hemoglobin with less large, medium, and small VLDL particle A1c (HbA1c) decreased from 7.3% to 6.6% in the intensive concentrations with a greater change in the LCKD for lifestyle group and 7.3% to 7.2% in the control group. medium and small VLDL particle concentration which Systolic and diastolic blood pressure, triglycerides, HDL was statistically significant. There was an increase in cholesterol (HDL-C), and urine albumin-to-creatinine VLDL particle size in the LCKD group vs the LFD group. ratio improved compared with control.10 Low-density lipoprotein particle size increased in both The other dietary extreme extends the Atkins groups with an increase in large LDL particle concentra- approach.11 Studies comparing a low carbohydrate (less tion and a decrease in medium and small LDL particle than 20 g Carbohydrates daily), ketogenic diet (LCKD) vs concentrations. Between groups, there was a statistically a low-fat diet (LFD) with less than