Wellness and Prevention
Preface
Vincent Morelli, MD Roger Zoorob, MD, MPH Guest Editors
Research in the fields of wellness and prevention has increased dramatically in the last decade, and, as a result, the public’s awareness and interest in these realms has also been heightened. Today, more than ever, our patients seem to be looking to us as ‘‘information analysts’’ to help them wade through the ever-rising sea of health information and misinformation that is widely distributed on the Internet and in other publications. This issue of Primary Care: Clinics in Office Practice will be divided into two parts. First we will examine the latest data in the prevention of our most noted killers: cardiovascular disease, diabetes, obesity, and cancer. The second part will examine the plethora of information surrounding wellness—our relatively new concept of health maximization. We will examine the current hard data, as well as the hopes and theoretical claims of manufacturers and alternative practitioners. Much scientific work has been done in these domains in recent years, but more remains to be done. Our aim is to separate fact from fiction, the known from the hoped for, and to delineate the strengths, weaknesses, and limits of current medical research. We hope that primary care providers and medical students will find our work well written, well researched, and clinically relevant. We are pleased and honored to serve as Guest Editors for this issue, and we feel privileged to have worked with such a distinguished group of collaborators. Many thanks to the contributing authors who have worked painstakingly to make their articles scholarly and relevant in the clinical setting. We also thank the Department of Family and Community Medicine at Meharry Medical College and the Family Medicine Program at Vanderbilt University for providing us with the support needed to complete this project. Thanks also to Elissa Clapp for her creative contributions and to The New
Prim Care Clin Office Pract 35 (2008) xiii–xiv doi:10.1016/j.pop.2008.07.016 primarycare.theclinics.com 0095-4543/08/$ – see front matter ª 2008 Elsevier Inc. All rights reserved.
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Orleans Healing Center for their inspiration and direction. Finally, our sincere thanks to our editor at Elsevier, Barbara Cohen-Kligerman, without whose help this project would never have been accomplished. Vincent Morelli, MD Family and Community Medicine Meharry Medical College 1005 Dr. DB Todd Boulevard Nashville, TN 37208 Roger Zoorob, MD, MPH Family and Community Medicine Meharry Medical College Family Medicine Residency 1005 Dr. DB Todd Boulevard Nashville, TN 37208 E-mail addresses:
[email protected] (V. Morelli)
[email protected] (R. Zoorob)
Preventing Hear t Dis eas e : Who Ne e ds to b e Concerne d a nd What to Do Mohamad Sidani, MD, MS*, Carol Ziegler, MS, RD, FNP KEYWORDS Antioxidants Vitamin E Vitamin B12 Vitamin C Folic acid Exercise
Cardiovascular disease (CVD) is the most prevalent health challenge to the global health care industry.1 Mortality from CVD accounted for 30% all mortality in the world during 2005. There were 7.2 million deaths from ischemic heart disease, 5.5 million deaths from cerebrovascular disease, and 3.9 million deaths from hypertension.1 It is projected that by the year 2010 CVD will be the leading cause of death in the developing world.2 For the past 80 years, CVD has been the leading cause of death in the United States and heavily burdens the economy at a cost of $314.1 billion in 2007.3 Although in the United States rates of CVD are elevated in rural compared with urban areas,4 these trends are reversed in nonindustrialized nations.5,6 Numerous epidemiologic studies link worldwide urbanization with adoption of adverse lifestyle changes and resultant increases in CVD.7 This effect may be attributable to decreases in physical activity and dietary fiber coupled with simultaneous increases in dietary fat and total calories consumed.8 Increased incidence of CVD is observed in immigrants who migrate to the United States when compared with those who have not expatriated. This same trend is seen in developing countries when citizens relocate from rural to urban areas.9–12 We could find no studies examining CVD when moving from third world cities where CVD risk is elevated, to United States cities where CVD is less prevalent than rural areas. The INTERHEART study identified risk factors associated with first myocardial infarction (MI). These risk factors include: family or personal history of previous MI, smoking, hypertension, specifically elevated systolic pressure, energy-dense/nutrient-poor diet, dyslipidemia, specifically elevated low density lipoprotein (LDL), physical inactivity, obesity, hyperglycemia, and type A personality.13 Many risk factors,
Meharry Medical College, School of Medicine, Department of Family and Community Medicine, 1005 Door, DB Todd Boulevard, Nashville, TN 37208, USA * Corresponding author. E-mail address:
[email protected] (M. Sidani). Prim Care Clin Office Pract 35 (2008) 589–607 doi:10.1016/j.pop.2008.07.007 primarycare.theclinics.com 0095-4543/08/$ – see front matter ª 2008 Elsevier Inc. All rights reserved.
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such as personal history of MI, hypertension, hyperglycemia, obesity, and dyslipidemia, are identified late in disease progression and 50% of men and 63% of women who die suddenly from MI have no prior symptoms or known risk.14 The goal of prevention is compression of morbidity and enhancement of quality of life through modification of lifestyle and environmental risk factors. Treatment of established cardiovascular disease is expensive and inefficient relative to disease prevention. Early implementation of preventive measures aimed at decreasing risks for hypertension, elevated lipids, obesity, and smoking may decrease death and disability from CVD by 50%.2 Several randomized controlled trials have examined the effect of various lifestyle changes on the reduction of established CVD. The Lifestyle Heart Trial examined the effect of intensive lifestyle changes (10% fat, whole food vegetarian diet, aerobic exercise, stress management training, smoking cessation, and group psychosocial support) on 5-year CVD risk and reported CVD regression and decreased incidence of MI in the experimental group compared with CVD progression and increased incidence of MI in the control group.15 Although such regimented lifestyle changes are difficult to maintain in ‘‘real life,’’ some effective dietary and lifestyle interventions are addressed. This article discusses some of the more common nonpharmacologic methods of preventing heart disease. Primary versus secondary prevention is discussed if applicable. SMOKING
It is well established that smoking increases risk for heart disease and death from MI.16–18 Encouraging patients not to start smoking and assisting current smokers by way of smoking cessation interventions are crucial in the prevention of heart disease. Secondhand smoke exposure is an independent risk factor in CVD and constant exposure to secondhand smoke doubles the risk for MI.19 The establishment of this public health risk has lead to the enactment of legislation banning smoking in many public areas and launched research over the concern of links between environmental air pollution and CVD. AIR POLLUTION
Concerns over environmental exposure to pro-atherogenic matter may have farreaching effects for global health policy. Epidemiologic research suggests that particulate matter smaller than 2.5 mm in diameter (PM2.5) may injure cardiovascular tissue and promote atherosclerosis. (PM2.5 is generally emitted from activities such as industrial and residential combustion and from vehicle exhaust.) In 2007 the worst three cities in the United States for exposure to this matter were Los Angeles, California; Pittsburgh, Pennsylvania; and Fresno, California. (A ranking of cities by annual PM2.5 exposure levels may be found at the American Lung Association Web site http://lungaction.org/reports/sota07_cities.html). Air pollution has in fact been linked to increased rates of heart disease and triggering MI,20 and surprisingly seems to have a more deleterious effect on cardiovascular than pulmonary tissues.21 The Women’s Health Initiative Study showed a 24% increase in CVD and a 76% increase in CV mortality per 10 mg/m3 increase in annual average PM2.5 level,22 establishing a strong link between environmental exposure to small particulate atmospheric matter and CVD mortality. Another cross-sectional exposure study found that for every 10 mg/m3 increase in PM2.5 levels, carotid intima-medial thickness increased 5.9%23 (for reference the EPA sets the United States standard of safety at an average of 15 mg/m3; Beijing, Cairo,
Preventing Heart Disease
and Delhi all have PM2.5 levels greater than 150 mg/m3). The impact of air quality on cardiovascular health needs to be investigated further, but people living in areas where there is a relatively significant level of exposure to small particulate matter shoulder an increased risk for CVD mortality and efforts aimed at reduction of exposure would be prudent in disease prevention. THE ROLE OF DIET IN CARDIOVASCULAR DISEASE PREVENTION
Calorie-dense/nutrient-poor diet is a well-established contributor to CVD risk.24,25 Recent research links the western diet with type 2 diabetes and CVD risk.26 Dietary modification is a primary intervention in treating established CVD and has traditionally focused on decreasing dietary fat. Several long-term studies, including the Lyon Heart study27 and Seven Countries study,28 demonstrate that the lipid-lowering effects of diet rival the effects of statins. The Seven Countries study revealed that people living on the island of Crete had low rates of CVD despite a moderate-fat diet.28 Out of this study emerged the concept of the Mediterranean diet as preventive for heart disease. THE MEDITERRANEAN DIET
The Mediterranean diet is characterized by high intakes of fish, fruits and vegetables, whole grains, olive and canola oils, and relatively lower intakes of meat and refined flours. The primary fat is olive oil, primary dairy foods are yogurt and cheeses, and intakes of red meat and poultry are limited. The diet is also punctuated by moderate consumption of wine. When compared with other CVD interventions, the Mediterranean diet is impressive as a tool for CVD prevention. In the Lyon Diet Heart Study,27 605 people who had similar CVD risk panels who had survived their first MI were randomized to follow the Mediterranean diet (n 5 302) or the American Heart Association (AHA) prudent diet (n 5 303). The trial was stopped after 1 year because of the remarkable beneficial effects observed in the experimental group in which Mediterranean diet decreased CVD risk by 72%, independent of serum lipid levels. A later single-blind, randomized trial of patients who had established CVD or risk factors for CVD demonstrated decreased risk for cardiac events in people on an Indo-Mediterranean diet (consisting of whole grains, legumes, fruits, vegetables, nuts, and soybean or mustard oil) compared with the National Cholesterol Education Program Step I prudent diet.29 Additionally a dose-dependent effect is observed with respect to adherence to the diet. The National Institutes of Health–AARP Diet and Health study examined high versus low adherence to the Mediterranean diet over 5 years and found increased adherence to the diet results in increased (22%) reduction in death from heart disease compared with low adherence.30 In another study of 180 men and women followed for 2 years, the diet resulted in decreased body weight, blood pressure, blood glucose, insulin levels, triglycerides, and total cholesterol, increased high density lipoprotein (HDL) cholesterol, and it actually reversed the metabolic syndrome in 56% of participants versus 13% on the AHA prudent diet.31 In this author’s opinion, based on current research, advising patients to follow a Mediterranean-style diet is a leading strategy in preventing CVD. DIETARY APPROACHES TO STOP HYPERTENSION DIET
The Dietary Approaches to Stop Hypertension (DASH) trial was an outpatient controlled feeding study that tested the effects on blood pressure of two experimental dietary patterns compared with a control dietary pattern similar to what many Americans eat. Both diets differed from the control diet in the type of carbohydrates they
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contained. Relative to the control diet, each experimental diet contained less refined grains and sweets and more whole grains, fruit, and vegetables. Results showed that the DASH diet did indeed reduce systolic and diastolic blood pressure in normotensives (by 6 and 3 points, respectively) and in hypertensives (11 and 6 points respectively). DASH also reduced total cholesterol, including LDL and HDL.25 Authors of the study postulated that the effect was attributable to increased vegetable and fiber consumption, subsequent increased mineral intake, and decreased intake of saturated fat and sodium. An inverse relationship has been established between fruit and vegetable consumption and cardiovascular disease risk.32,33 Vegetarian diets have been shown to decrease risk for dying of heart disease by 24% in epidemiologic studies.34 CALORIC RESTRICTION
Caloric restriction is believed to prolong life expectancy and reduce incidence of chronic disease in humans and involves a reduction in total calories while maintaining nutritional adequacy by eating predominantly nutrient-dense foods. One small study compared 18 people currently following caloric restriction (
