Medical Nutrition Therapy in Cardiovascular Disease Chapter 35 Medical Nutrition Therapy in Cardiovascular Disease

Coronary Heart Disease (CHD) or Coronary Artery Disease (CAD) Disease involving the network of blood vessels surrounding and serving the heart Manifested in clinical end points of myocardial infarction (MI) and sudden death 10

Cardiovascular Disease (CVD) CVD has been the leading cause of death in the United States for every year since 1900, except 1908. CVD kills almost as many people yearly as the next seven causes of death combined.

Prevalence and Incidence The United States ranks 14th and 16th, among industrialized nations for the prevalence of CVD in women and men, respectively. More than 61 million Americans have at least one form of CVD (i.e., hypertension, CHD, stroke, rheumatic heart disease, or congestive heart failure). The incidence of CHD is high; an American experiences a coronary event almost every 29 seconds.

Natural Progression of Atherosclerosis (From Harkreader H. Fundamentals. Philadelphia: W.B. Saunders, 2000)

Plaque That Has Been Surgically Removed from Coronary Artery Courtesy Ronald D. Gregory and John Riley, MD.

Prevention Blood lipids and lipoproteins Total cholesterol Total triglycerides Lipoproteins and metabolism —Chylomicrons, VLDL, IDL, LDL, HDL

Functions of the Plasma Lipoproteins Chylomicron—Transport of dietary triglyceride VLDL—Transport of endogenous triglyceride IDL—LDL precursor LDL—Major cholesterol transport lipoprotein HDL—Reverse cholesterol transport

Lipoprotein Assessment Includes measurement of total cholesterol, LDL cholesterol, HDL cholesterol, and triglyceride level after fasting

Cardiovascular Risk Factors Category I—cigarette smoking, LDL cholesterol, high-fat diet, hypertension Category II—diabetes mellitus, physical inactivity, HDL cholesterol, TG, obesity Category III—psychosocial factors, lipoprotein a, homocysteine Category IV—age, male gender, low socioeconomic status, family history

Quantity of Soluble Fiber Needed Daily to Produce Lipid-Lowering Effect Pectin: 6 to 40 g Gums: 8 to 36 g Dried beans or legumes: 100 to 150 g Dry oat bran: 25 to 100 g Oatmeal: 57 to 140 g Psyllium: 10 to 30 g

Genetic Hyperlipidemias Familial hypercholesterolemia Familial combined hyperlipidemia Familial dyslipidemia Familial dysbetalipoproteinemia

Nutrient Composition of the Therapeutic Lifestyle Change Diet Saturated fat Polyunsaturated fat Monounsaturated fat Total fat Carbohydrate Fiber Protein Cholesterol Total calories (energy)

Category I Risk Factors for Coronary Heart Disease Cigarette smoking Elevated LDL and total cholesterol Hypertension Left ventricular hypertrophy (LVH) Thrombogenic factors

Category II Risk Factors for Coronary Heart Disease Diabetes mellitus types 1 and 2 Physical inactivity Low HDL cholesterol Obesity Menopausal factors

Major Disease Processes Contributing to Coronary Heart Disease Atherosclerosis—chronic (long-term development) Thrombosis—acute (late and brief event)

Pathophysiologic Steps in Development of Coronary Heart Disease/Myocardial Infarction Phase 1 Fatty streaks (atherogenesis) Phase 2 Atheroma (or plaque) formation Phase 3 Complicated lesions with rupture (nonocclusive thrombosis) Phase 4 Complicated lesions with rupture and occlusive thrombosis Phase 5 Fibrosis (occlusive) lesions

Hyperlipidemias Elevated blood triglycerides and/or cholesterol Lipoproteins found in blood Chylomicrons = postprandial dietary fat Very-low-density lipoproteins (VLDL) = lipid being transported from liver to peripheral tissue Low-density lipoproteins (LDL) = transport of cholesterol High-density lipoproteins (HDL) = reverse transport of cholesterol, tissues to liver Type of hyperlipidemia depends upon portion of particles present 5

LDL and HDL Cholesterol Laboratory Values Predict Risk of CHD LDL-C >130 mg/dl HDL-C <35 mg/dl Total cholesterol (TC) >200 mg/dl Total triglycerides (TG) >150 mg/dl Formula: LDL-C = TC – HDL-C–(TG/5) 13

HDL Cholesterol Levels Predict Risk of Coronary Heart Disease Increased by: Exercise Weight loss Moderation of alcohol Decreased by: Obesity No exercise Cigarettes Androgenic steroids B blockers High TGs Genetic factors 12

LDL Cholesterol Levels Predict Risk of Coronary Heart Disease Increased by Fat in diet Obesity Diabetes Hypothyroidism Decreased by Estrogen 11

Primary Prevention with Lipoprotein Analysis (From National Cholesterol Education Program: Second Report of the Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel II). National Institutes of Health, NIH Publication No. 93-3095. Bethesda, MD: National Heart, Lung, and Blood Institute, 1993.)

Primary Prevention in Adults without Evidence of CHD: Initial Classification Based on Total Cholesterol and HDL Cholesterol (From National Cholesterol Education Program: Second Report of the Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel II). National Institutes of Health, NIH Publication No. 93-3095. Bethesda, MD: National Heart, Lung, and Blood Institute, 1993.) HDL = high-density lipoprotein.

Diet Therapy for High Blood Cholesterol (Data from National Cholesterol Education Program [NCEP]. Second Report of the Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults [Adult Treatment Panel II]. NIH Publication N. 93-3095. Bethesda, MD; National Institutes of Health. National Heart, Lung, and Blood Institute, 1993.) * Calories from alcohol not included.

General Goals for Treatment of Hyperlipidemias Achieve IBW. Decrease simple sugars and alcohol. Decrease total fat, especially cholesterol and SFA. Increase complex carbohydrate and fiber. 6

Lipid-Lowering Drugs Added if Diets Are Not Successful After a 6-month trial on each diet, drugs are added to the treatment. Types: Nicotinic acid and lovastatin Gemfibrozil, probucol, clofibrate— for high TGs Cholestyramine and colestipol (bile acid sequestrants)—to lower high cholesterol; may increase TGs 8

Myocardial Infarction (MI) Coronary Infarction, Coronary Thrombosis, or Heart Attack Some part of coronary circulation blocked Ischemia leads to muscle destruction Diagnosis: ECG; blood levels of enzymes such as LDH and CPK 14

Myocardial Infarction—MI Postinfarction nutrition 1. 1st 24 hrs: no caffeine, liquid diet (nausea and choking are common) 2. Small frequent meals; soft or liquid diet 3. Na+ restriction if BP and fluid status indicate 4. Consistent diet information 5. Drugs that cause nausea—digitalis, morphine 15