Primary Prevention A Focus on Lifestyle

The Big Heart Disease Lie

Foods to eat if you have Heart Disease

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Key Points

The five key elements of a healthy lifestyle are:

1. Not smoking.

2. Consuming 5 servings of fruits or vegetables each day.

3. Ten minutes of relaxation, silence, or meditation daily for stress reduction.

4. Maintaining BMI less than 30 kg/m2 and working to bring it down toward 18.5 kg/m2.

5. Exercising for at least 150 minutes a week (about 20 minutes daily), equivalent to at least brisk walking.

The five key elements may be simply communicated to patients by the numbers 0-5-10-30-150.

Only about 3% of the U.S. population has a healthy lifestyle as defined by criteria 1, 2, 4, and 5 above.

The potential benefits of a healthy lifestyle are:

• A 40% to 65% reduction in all-cause mortality.

• An 81% to 87% reduction in coronary heart disease events.

• A 67% reduction in all cardiovascular diseases.

• A 58% to 93% reduction in the risk of developing type 2 diabetes.

A clinical practice may choose a broad, primary prevention approach rather than a single focus on prevention of coronary heart disease. Between 2000 and 2009, nine major

Heart healthy measures

10 leading causes of death in 2006, ages 50-85 years

Heart healthy measures

#1

Stop smoking

.____

Heart disease

Figure 7-1 A single intervention with a simple, comprehensive medical approach to coronary risk has a significant impact on all 10 of the most common causes of death in the United States. A line is drawn from each of 10 potential cardiac risk interventions on the left side to all the causes of death that each intervention would also tend to reduce.

Vitamin supplementation (folate, Vitamin D, etc.

Figure 7-1 A single intervention with a simple, comprehensive medical approach to coronary risk has a significant impact on all 10 of the most common causes of death in the United States. A line is drawn from each of 10 potential cardiac risk interventions on the left side to all the causes of death that each intervention would also tend to reduce.

studies demonstrated that a healthy lifestyle is associated with large reductions in all-cause mortality and major reductions in multiple disease-specific outcomes. These studies succinctly define what should be understood by the term "healthy lifestyle." These primary prevention studies demonstrate that persons who have a number of healthy characteristics at the beginning of a period of observation enjoy remarkable benefits over periods ranging from 4 to 20 years.

The evidence chain begins with the Nurses' Health Study (Hu et al., 2001; Stampfer et al., 2000). In 84,129 participants followed up for 14 years, the effects of several lifestyle factors were analyzed, including not currently smoking, body mass index (BMI) less than25 kg/m2, alcohol consumption at least 0.5 drinks per day, at least 0.5 hour daily of moderate to vigorous physical activity, and adhering to several dietary elements (increased intake of cereal fiber, marine omega-3 fatty acids, and folate; increased polyunsaturated/saturated fat ratio; and low trans fat intake and glycemic load). The group defined as "low risk" had all these characteristics. After 14 years, this low-risk group (3% of original study population) had an 83% reduction in coronary disease events. Another analysis of the same cohort showed that women at low risk also had a 91% reduction in the risk of developing diabetes.

In 2002 the Diabetes Prevention Program Research Group published the results of the only RCT among these lifestyle studies. This study focused solely on the outcome of type 2

diabetes among 3324 nondiabetic patients. The "standard" healthy lifestyle intervention consisted of written information provided at the beginning of the study and an annual 20- to 30- minute individual counseling session. The defined "standard" lifestyle goals included instructions to adhere to the U.S. Department of Agriculture (USDA) Food Guide Pyramid and the equivalent of an NCEP Step 1 diet; to reduce weight; and to increase physical activity. Subjects were randomized to standard lifestyle intervention plus metformin (875 mg twice daily), to standard lifestyle intervention plus placebo, or to "intensive" lifestyle intervention alone. The latter group was encouraged to achieve and maintain a weight reduction of at least 7% of initial body weight through a healthy low-calorie, low-fat diet and to engage in physical activity of moderate intensity, such as brisk walking, for at least 150 minutes per week. Subjects in this group also received a 16-lesson curriculum, taught by case managers on a one-to-one basis during the first 24 weeks after enrollment, with brief follow-up sessions monthly. After an average follow-up of only 2.8 years, the intensive lifestyle intervention was associated with a reduced incidence of diabetes (58% vs. 31% reduction with metformin, both compared to placebo). The intensive lifestyle intervention was significantly more effective than the standard lifestyle intervention plus metformin.

In the Healthy Aging: A Longitudinal Study in Europe (HALE Project), in 2539 participants age 70 to 95 at baseline, investigators found a 65% reduction in all-cause mortality and 67% to 77% reductions in disease-specific risks for coronary heart disease, any cardiovascular disease, and cancer in the group with four healthy lifestyle factors (never smoking, Mediterranean diet, 3-4 hours/week of moderate physical activity, and glass of wine or more daily) compared with the group with none of these healthy characteristics (Knoops et al., 2004).

The Women's Health Study analyzed smoking, alcohol use, exercise, BMI, and diet among 37,636 participants age 45 or older. After a mean of 10 years follow-up, there were risk reductions of 55% for total stroke and 71% for ischemic stroke; the risk-adjusted hazard ratio for participants who scored higher on an index of lifestyle factors than those who scored lower was 0.45 for total stroke and 0.29 for ischemic stroke (Kurth et al., 2006).

In the Health Professionals Follow-up Study, 42,847 men age 40 to 75 were followed over 16 years using similar healthy lifestyle criteria. "Low risk" was defined as the absence of smoking, BMI less than 25 kg/m2, moderate to vigorous activity of at least 30 minutes a day, moderate alcohol consumption (5-30 g/day), and the top 40% of the distribution for healthy diet score. Compared with men with no healthy lifestyle factors, those with all five factors had an 87% reduction in the risk of developing coronary heart disease (Chiuve et al., 2006).

In the Atherosclerosis Risk in Communities Study (ARIC), the effects of four healthy lifestyle factors (>5 servings of fruits and vegetables per day, >2.5 hours of exercise per week, BMI of 18.5-30 kg/m2, not smoking) were analyzed in 15,708 participants followed for only 4 years. Among subjects who had no healthy characteristics at baseline, those who changed their behavior and adopted a healthy lifestyle (all four habits) experienced a lower risk (40% reduction) of all-cause mortality and a 35% reduction in cardiovascular disease (King et al., 2007). This study is particularly important because it indicates clearly that those with a relatively unhealthy lifestyle who change in midlife can still achieve dramatic reductions in health risks and longer life expectancy.

The European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk study demonstrated significant reductions in all-cause mortality with increasing numbers of health factors in 20,244 participants followed for a mean of 11 years. The four factors analyzed were current nonsmoking status, engaging in regular physical activity, moderate alcohol use, and plasma vitamin C level greater than 0.88 ng/dL, as a surrogate for fruit and vegetable consumption. Individuals with all four factors had an advantage of approximately 14 years in chronologic age over those with only one of the four factors (Khaw et al., 2008).

Further follow-up analysis of the 43,685 individuals in the Health Professionals Follow-up Study and the 71,243 participants in the Nurses' Health Study showed that a healthy lifestyle was associated over time with a 69% reduction in the risk of developing an incident stroke among men and a 79% reduction of stroke risk among women (Chiuve et al., 2008).

The most recent major study in this line of evidence that changes in lifestyle behavior lead to remarkable changes in health outcomes is the "Healthy Living Is the Best Revenge" report. Ford and colleagues (2009) used data from 23,153 German participants age 35 to 65 from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam study. They analyzed end points of type 2 diabetes mellitus, myocardial infarction, stroke, and cancer and the effect of four healthy lifestyle factors: never smoking, BMI less than 30 kg/m2, 3.5 hours/week of physical activity or more, and adhering to healthy dietary principles (high intake of fruits, vegetables, and whole-grain bread; low meat consumption). Fewer than 4% of participants had zero healthy factors; most had one to three healthy factors, and 9% of the group had all four factors. During a follow-up of 7.8 years, after adjusting for age, gender, educational status, and occupational status, the hazard ratio for developing a chronic disease decreased progressively as the number of healthy factors increased. Participants with all four factors at baseline (vs. those with none) had a 78% lower risk of developing a chronic disease. The risk of developing diabetes was reduced by 93%, the risk of myocardial infarction by 81%, risk of stroke by 50%, and risk of cancer by 36%.

The results of these studies are summarized in Tables 7-3 and 7-4. Despite minor variations, there is now substantial consensus on what constitutes a "healthy lifestyle." Briefly stated, a healthy lifestyle consists of the following:

1. Not smoking

2. Five (5) servings of fruits and vegetables a day

3. Body mass index (BMI) less than 30 kg/m2

4. About 150 minutes of exercise a week (~20 min/day)

Consider a fifth lifestyle factor: stress reduction or relaxation.

The previous studies did not include this variable in their design most likely because of the difficulty in measuring effects. Nevertheless, substantial literature on this subject suggests (but does not prove) significant beneficial effects on blood pressure, smoking, alcohol abuse, cholesterol, psychosocial stress, atherosclerosis (measured by carotid artery

Table 7-3 Summary Data for the Eight Major Prospective Lifestyle Studies

Study

N

Ages

Follow-up (years)

m2)

Exercise (min/wk)

Diet

Other

Nurses' Health Study (2000)

84,129

30-55 in 1976

14

Not currently

<25

210

Top 40%*

Alcohol: / drink/day

Lifestyle or Metformin for Prevention of Diabetes (2002)

3234t

>25

2.8

Not specified

>24

150

NCEP Step 1 diet

Healthy Aging: A Longitudinal Study in Europe (HALE Project) (2004)

2339

70-95

10

Never, or quit >15 years

200$

Mediterranean Diet Score = 8§

Alcohol: >0 glass/day

Women's Health Study (2006)

37,636

>45

10

Never

<22, 22-24.9 25-29.9 30-34.9 > 35

Never/rare <1 time/wk 2-3 x/wk > 4 x/wk

<1, 1-3, 4-10.5, >10.5

Health Professionals Follow-up (2006)

42,847

40-75 in 1986

16

Not currently

<25

210

5-30 g

Atherosclerosis Risk Factors in Communities (ARIC) (2007)

15,708

45-64

6

Not currently

18.5-30

>150

5 servings of fruits and vegetables daily

Alcohol: 1-14 units/ wk

EPIC-Norfolk (2008)

20,244

45-79

11

Not currently

--- —

210

Vitamin C level >50 mmol/L#

Alcohol: 1-14 units

EPIC-Potsdam (2009)

23,153

35-65

7.8

Never

<30

210

Composite**

*Diet criterion: highest 40% of the cohort for consumption of a diet high in cereal fiber, marine n-3 fatty acids, and saturated fat, and low in trans fat and glycemic load. Subjects were selected based on criteria of age >25, BMI >24, and either fasting blood glucose or post-75-g glucose load; 2-hour postprandial glucose elevated but not diagnostic for diabetes.

¿Individuals with a score in the intermediate and the highest tertile on the Voorrips or Morris questionnaire were considered the low-risk group for physical activity.

§For the Mediterranean Diet Score, the subject must have had above-average consumption of the six positive variables: (1) polyunsaturated/saturated fatty acid ratio, (2) fruits, (3)

vegetables, (4) legumes, (5) fish, and (6) grains. They also must have had below-average consumption of the two adverse factors: (7) red meat and (8) dairy products.

^Considered six dietary factors: cereal fiber, folate, polyunsaturated/saturated fat ratio, omea-3 fatty acids, trans fats, and glycemic load, grouped into deciles and scored as 0 to 9.

Calculated a summary dietary score based on the Alternate Healthy Eating Index (AHEI).

#As a proxy for 5 servings of fruits and vegetables per day.

**A healthy diet was considered to consist of high intake of fruits and vegetables, whole-grain bread, and low consumption of meat. NCEP, National Cholesterol Education Program; EPIC, European Prospective Investigation into Cancer and Nutrition.

intima-media thickness), angina, left ventricular hypertrophy, and overall mortality. A review of controlled trials using Transcendental Meditation (TM) techniques (many of which also compared TM to progressive muscle relaxation and other stress reduction techniques) found the following (Walton et al., 2004):

• Significant blood pressure reductions (11 mm Hg systolic and 6 mm Hg for diastolic) among elderly blacks (Alexander et al., 1996a; Schneider et al., 1995).

• A 13% reduction in cigarette use and smaller but significant reductions in drug and alcohol use (Alexander et al., 1994).

• Significant reductions in cholesterol after 11 months (Cooper and Aygen, 1979).

• A 30% reduction in psychosocial stress (Eppley et al., 1989).

• Implied reductions in atherosclerosis in patients with two or more risk factors for coronary heart disease of 33% after 1 year (Alexander et al., 1994, 1996a; Fields et al., 2002).

• Reduction in the likelihood of heart attack or stroke of 11% among elderly blacks (Alexander et al., 1994, 1996a).

• Greater exercise tolerance, maximal workload, delayed onset of ST-segment depression after 8 months (Zamarra et al., 1996).

• A highly significant reduction in all-cause mortality (Alexander et al., 1989, 1996b).

These studies are generally older, small in size, and of relatively poor methodologic quality (University of Alberta, 2007). However, these findings are supported by the INTER-HEART study, which identifies psychosocial stress as one of the nine leading risk factors for MI (Rosengren et al., 2004; Yusuf et al., 2004).

A relaxation or stress reduction variable is added to the basic lifestyle formula for two main reasons: (1) the mounting support from clinical research and (2) the epidemiologically well-established correlation of stress to overall morbidity and mortality (Figueredo, 2009). Also, a compelling com-monsense belief among the general public holds that stress is bad for health and can be reduced by various behaviors.

Table 7-4 Outcomes of the Eight Major Prospective Lifestyle Studies

Study

Healthy Lifestyle at Baseline*

Major Findings

Nurses' Health Study (2000)

3%

83% reduction in coronary heart disease (CHD) events; follow-up study showed a 91% reduction in the risk of type 2 diabetes.

Lifestyle or Metformin for Prevention of Diabetes (2002)

58% reduction in diabetes compared to placebo; vs. 31% reduction with metformin and "standard" lifestyle intervention.

Healthy Aging: A Longitudinal Study in Europe (HALE Project) (2004)

65% reduction in all-cause mortality (all 4 points); 77% reduction in CHD; 67% reduction in all cardiovascular diseases; and 68% reduction in all cancers.

The lack of any healthy lifestyle characteristics was associated with a population-attributable risk of 60% of all deaths, 64% of deaths from CHD, 61% from all cardiovascular diseases, and 60% from cancer.

Women's Health Study (2006)

4.7%

55% reduction of total stroke, 71% reduction ischemic stroke, and 27% increase in hemorrhagic stroke.

Health Professionals' Follow-up Study (2006)

87% reduction in men for CHD; 62% of coronary events might have been prevented with the five healthy lifestyle factors; in men taking medication for hypertension or hypercholesterolemia, 57% of all coronary events may have been prevented with a low-risk lifestyle. Compared with men who did not make lifestyle changes during follow-up, those who adopted two or more additional low-risk lifestyle factors had a 27% lower risk of CHD.

Atherosclerosis Risk Factors in Communities (ARIC) (2007)

8.5%

During 4 years of follow-up, total mortality and cardiovascular disease events were lower for new adopters (2.5% vs. 4.2%) and 11.7% vs. 16.5% compared to individuals who did not adopt a healthy lifestyle. New adopters had 40% lower all-cause mortality and 35% fewer cardiovascular events.

EPIC-Norfolk (2008)

Adjusted relative risks for all-cause mortality for men and women who had 3, 2, 1, and 0 risk factors compared to 4 healthy behaviors were 1.39, 1.95, 2.52, and 4.04, respectively. All 4 behaviors = 14 more years of life.

EPIC-Potsdam (2009)

9%

Subjects with all 4 factors at baseline had a 78% lower risk of developing a chronic disease: diabetes, 93% reduction; myocardial infarction, 81% reduction; stroke, 50% reduction; and cancer, 36% reduction.

*Prior data on the prevalence of healthy lifestyle characteristics among U.S. adults demonstrated that only 3% had all four healthy lifestyle factors: not smoking, 5 servings of fruits and vegetables a day, 150 minutes of exercise a week, and body mass index (BMI) of 18.5 to 25 kg/m2. (Reeves MJ, Rafferty AP. Healthy lifestyle characteristics among adults in the United States, 2000. Arch Intern Med 2005;165:854-857.)

Currently, the data do not precisely define the minimum time needed in meditation or relaxation to achieve health benefits; many studies use 15 to 20 minutes daily (Lane et al., 2007). A reasonable conjecture of the "minimal effective dose," which follows the work of Depak Chopra (1993), is 10 minutes a day. Chopra believes that nothing more than 10 minutes of silence is required. Progressive increases in time will enhance the benefits, but a place to start is needed, as with the BMI criterion.

Thus, the revised list of essential components for a healthy lifestyle is as follows:

1. Not smoking

2. Five (5) servings of fruits and vegetables daily

3. Ten (10) minutes of relaxation or meditation exercise daily

4. BMI less than 30 kg/m2

5. Exercise for at least 150 minutes per week

This can be conveniently expressed by the simple numeric mnemonic 0-5-10-30-150, as follows:

O

Cigarettes a day

5

Servings of fruits and vegetables a day

1O

Minutes of relaxation or meditation daily

3O

BMI less than 30

15O

Minutes of exercise a week

This is a concise notation for a prescription of 0 cigarettes a day, 5 servings of fruits and vegetables every day, 10 minutes of relaxation or meditation daily, a BMI less than 30, and 150 minutes of exercise each week. For a behavioral lifestyle intervention to be practical and acceptable to most physicians, it should be brief, easily memorable, and simple to communicate to patients.

The nine studies clearly indicate that certain lifestyle characteristics are associated with important reductions in both chronic disease and death. Also, only 3% to 9% of typical populations meet the varying requirements of a healthy lifestyle; the relevant number for the U.S. population from the national Behavioral Risk Factor Surveillance System is 3% (BRFSS, 2002). There is a huge population of people who do not have a healthy lifestyle and whom physicians can help by facilitating their transition to a healthier lifestyle.

Of the studies previously described, in many ways the ARIC Study and the Prospective Diabetes Group trial are arguably the most important. These studies show directly that subjects who previously had a suboptimal lifestyle up into middle age can experience proportional benefits in health outcomes by making changes in their behavior at that time. These studies do not, however, tell us that physicians can persuade patients to make corresponding changes in their behaviors.

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