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Reversing Chronic Diseases Using Lifestyle Medicine 

Reversing Chronic Diseases Using Lifestyle Medicine
Chapter:
Reversing Chronic Diseases Using Lifestyle Medicine
Author(s):

Benjamin R. Brown

DOI:
10.1093/med/9780190241254.003.0014
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date: 23 November 2020

In memory of the lives and work of our friends and colleagues, James Billings, PhD, Lee Lipsenthal, MD, and Glenn Perelson, who served for many years at the nonprofit Preventive Medicine Research Institute.

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Introduction

Over 86% of the $3.0 trillion in annual healthcare costs in the United States are due to chronic diseases that can often be prevented or even reversed by making comprehensive lifestyle changes.

Lifestyle medicine is an exciting and rapidly growing movement in medicine today in which comprehensive lifestyle changes are used not only to prevent but also often to reverse the progression of many chronic diseases. These include even severe coronary heart disease, type 2 diabetes, hypertension, obesity, hyperlipidemia, and early-stage prostate cancer. Anecdotal evidence exists indicating that these comprehensive lifestyle changes may also beneficially affect the progression of early-stage breast cancer, some autoimmune conditions, multiple sclerosis, and Alzheimer’s disease.

Many forces are converging that make this the right idea at the right time. While the limitations of drugs and surgery for treating and preventing chronic diseases are becoming increasingly well documented, the power of comprehensive lifestyle changes are also becoming increasingly well recognized. Changes in how medical care is reimbursed are also paving the way for lifestyle medicine as this approach to chronic illness not only increases quality of life but also saves money.

A guiding principle of lifestyle medicine is that it is usually more powerful to address the underlying causes of diseases rather than treating only the symptoms. Imagine a group of doctors busily mopping up the floor around an overflowing sink, yet no one is turning off the faucet.

To a remarkable degree, the faucet—the underlying cause of many chronic diseases—represents the lifestyle choices we make each day. These include:

  • a whole foods, plant-based diet (naturally low in fat and refined carbohydrates);

  • stress management techniques (including yoga and meditation);

  • moderate exercise (such as walking); and

  • social support and community (love and intimacy).

In short—eat well, move more, stress less, and love more.

Many people tend to think of advances in medicine as high-tech and expensive, such as a new drug, laser, or surgical procedure. They may have a hard time believing that something as simple as these comprehensive lifestyle changes can make such a powerful difference in our lives—but they often do. Lifestyle medicine is a disruptive technology, akin to an electric car or an iPhone, not just an incremental change.

In our research, we have used high-tech, expensive, state-of-the-art scientific measures to prove the power of these simple, low-tech, and low-cost interventions. These randomized-controlled trials and other studies have been published in leading peer-reviewed medical and scientific journals.

The Paradox of Comprehensive Lifestyle Changes: How Do People Make and Sustain Comprehensive Changes?

We have learned that our bodies often have a remarkable capacity to begin healing—and much more quickly than had once been realized—when we treat these underlying lifestyle causes. And because the underlying biological mechanisms are so dynamic, most people feel so much better, so quickly, it reframes the reason for making lifestyle changes from fear—for example, preventing something bad from happening, such as a heart attack or stroke—to joy and pleasure. Fear is not a sustainable motivator, but joy and pleasure are. What a person has gained is so much more significant than what they have given up.

For example, in all of our studies and demonstration projects, patients with even severe coronary heart disease reported a greater than 90% reduction in angina (chest pain) frequency in just a few weeks. When someone who cannot work, cannot walk across the street before the light changes, cannot make love with their partner, or cannot play with their kids due to chest pain, finds that they can do all of these activities after making these changes for only a few weeks, these choices shift from being a sacrifice to being a gateway to a renewed life and naturally become sustainable.

The paradox here is that we often think of taking a medication as easy and making these lifestyle changes as hard, but when you look at the adherence data it would imply just the opposite. In our studies, adherence was 85%–90% in 3,780 men and women at all 24 sites after 1 year, comparing this with the studies done on statin adherence in adults showing that one-half to two-thirds of patients prescribed statins are not taking them after 1 year. In patients age 65 years or older, adherence to statins for primary prevention after 2 years was 25.4%. Even in patients with documented CAD, Duke University researchers showed that consistent use of all three therapies (aspirin, statins, and beta-blockers) was only 21%.1

Selected Clinical Research on Lifestyle Medicine to Prevent Chronic Diseases

Healthcare costs for cardiovascular disease are more than for any other diagnostic group. In 2012, the estimated annual healthcare costs for cardiovascular disease were $316.6 billion, including $193.1 billion in direct costs (hospital services, physicians and other professionals, prescribed medications, home healthcare, and other medical durables) and $123.5 billion in indirect costs from lost future productivity. By comparison, the estimated direct cost of all types of cancer that year was $88.7 billion (50% for outpatient or doctor office visits, 35% for inpatient care, and 11% for prescription drugs).2

Despite the prevalence and costs of cardiovascular disease, it is primarily a preventable and even reversible lifestyle illness. Most of the total deaths per year from heart disease and stroke are preventable by lifestyle and medications.3

For example, The INTERHEART study followed 30,000 men and women in seven continents and found that nine risk factors modifiable by intensive lifestyle changes accounted for 94% of the risk of a myocardial infarction in women and 90% of the risk in men. Abnormal lipids; smoking; hypertension; diabetes; abdominal obesity; psychosocial factors; consumption of fruits, vegetables, and alcohol; and regular physical activity account for most of the risk of myocardial infarction worldwide in both sexes and at all ages in all regions.4

Another study looking prospectively at over 20,000 men found that those who followed a healthy diet, did not smoke, exercised moderately, and did not have excessive belly fat reduced their risk of a heart attack by 80%.5

Thus, the disease that accounts for more premature deaths and costs than any other illness is almost completely preventable simply by changing diet and lifestyle. And the same lifestyle changes that can prevent or even reverse heart disease may also help prevent or even reverse many other chronic diseases as well.

In the European Prospective Investigation into Cancer and Nutrition (EPIC) study, patients who adhered to healthy dietary principles (low meat consumption and high intake of fruits, vegetables, and whole-grain bread), never smoked, were not overweight, and had at least 30 minutes a day of physical activity had a 78% lower overall risk of developing a chronic disease. This included a 93% reduced risk of diabetes, an 81% lower risk of heart attacks, a 50% reduction in risk of stroke, and a 36% overall reduction in risk of cancer, compared with participants without these healthy factors.6

The Four Parts of the Program

Our program included intervention across four areas—diet, stress management, exercise, and group support.

The Diet

The approach to nutrition is an abundant low-fat plant-based nutrition plan. This plan emphasizes:

  • Whole grains: 6 or more servings a day

  • Fresh fruits 2–4 servings a day and vegetables 3 or more servings a day

  • Plant protein 3–5 servings a day: Legumes and beans with soy products, egg whites, and meat analogues as options.

  • Optional

    • Nonfat dairy 0–2 servings a day.

    • Refined carbohydrates and nonfat sweets 0–2 servings a day.

    • Alcohol 0–1 serving a day.

    • Low-fat foods in limited amounts 0–3 servings a day.

When a person eats this way, without adding oil, the fat content comes out to approximately 10% and cholesterol is 10 mg or less a day. This eating program has been adapted for people following a FODMAPS diet, a gluten-free diet, and a full vegan diet as well as people on dialysis. Modifications can be made if people are losing weight too fast or have increased protein needs for other health reasons.

Stress Management

The stress management techniques included stretching exercises, breathing techniques, meditation, progressive relaxation, and imagery. The purpose of each technique is to increase the participants’ sense of relaxation, concentration, awareness, resiliency, and well-being. Participants were asked to practice these stress management techniques for at least one hour per day.

Exercise

Participants were asked to exercise a minimum of 3 hours per week and to spend a minimum of 30 minutes per session exercising within their prescribed target heart rates and/or perceived exertion levels. Two strength training sessions were added later and are now included in the program.

Group Support

Group support sessions were designed to increase social support and a sense of community by creating a safe environment for the expression of feelings and also to help participants adhere to the lifestyle-change program. The methodology of the support group is surprisingly simple, participants learn to listen with empathy and speak their feelings. These simple practices transform relationships, and people often feel understood on a deeper level then they ever have. As they practice this weekly, trust and intimacy develops and participants report no longer feeling isolated and alone.

Selected Clinical Research on Lifestyle Medicine as Treatment to Reverse Chronic Diseases

From 1978 through 1991 we conducted pilot, follow-up and 5-year studies to assess the outcomes of lifestyle medicine in coronary heart disease.

Pilot Study

In 1978, we began a series of studies spanning four decades demonstrating the power of a lifestyle medicine intervention, beginning with coronary heart disease.

In the first study, 10 patients with severe coronary artery disease were housed in a hotel for 30 days and asked to make these comprehensive lifestyle changes.

During this time, patients reported a 91% reduction in the frequency of angina, clinically and statistically significant improvements in all modifiable cardiac risk factors, and improved well-being, including enhanced cognitive function and functional status. Eight of these 10 patients showed improvements in myocardial perfusion as measured by exercise thallium scintigraphy.7 Although there was no randomized control group, it is highly unusual for patients to improve to this degree in such a short time.

Follow-Up Study with Randomized Control Group

To address this issue, in 1990 we conducted a randomized-controlled trial in which experimental group patients were housed in a residential setting and asked to make these comprehensive lifestyle changes. After 24 days, patients again reported a 91% reduction in frequency of angina, significant improvements in all modifiable cardiac risk factors, and improved well-being, including enhanced cognitive function and functional status.

In addition, there were significant improvements in the ejection fraction response from rest to peak exercise as measured by exercise radionuclide ventriculography. There was also significant improvement in regional wall motion when compared to the randomized control group.8

Lifestyle Heart Trial and 5-Year Follow-Up Study

The Lifestyle Heart Trial began in 1986 with 48 subjects randomized to either the intensive lifestyle intervention described earlier or to usual care. Clinical entry criteria included age between 35 and 75 years; no coexisting life-threatening illness; lack of myocardial infarction within 6 weeks of the start of the trial; not currently taking lipid-lowering medication; single, double, or triple vessel coronary disease in nonrevascularized vessels with at least one proximal lesion greater than 75% stenosed; left ventricular ejection fraction greater than 25%.

The original Lifestyle Heart Trial was a 1-year study; based on the results after one year, the National Heart, Lung, and Blood Institute of the National Institutes of Health provided funding to extend the trial for 4 additional years.

Endpoint measurements included: (1) quantitative coronary arteriography at baseline, 1 year, and 5 years to assess the extent of coronary atherosclerosis; (2) cardiac PET scans to measure myocardial perfusion; (3) lipoprotein and apolipoprotein profiles; (4) 3-day diet diaries and other questionnaires designed to measure adherence; (5) psychosocial questionnaires to evaluate change in quality of life; (6) quantitative coronary arteriography and cardiac PET scans blindly read by independent observers; and (7) cardiac events.

After 5 years, experimental patients were exercising an average of 3.6 hours per week, practicing stress management 5.7 hours per week, and consuming an average of 18.6 mg per day of cholesterol and 8.5% of total calories from fat. Control patients were exercising 2.9 hours per week, practicing stress management techniques 0.98 hours per week, and consuming an average of 138.7 mg per day cholesterol and 25% of total calories from fat.

From baseline to 1 year, experimental group patients reported a 91% reduction in frequency of angina, whereas the control group reported a 186% increase in frequency (Table 14.1).

Table 14.1 Results at One Year

Study Group

Control Group

disease regression for 82%

disease progression for 53%

91% decrease in anginal frequency

186% increase in anginal frequency

37% decrease in LDL, without medication

minimal change in LDL

percent diameter stenosis improved

percent diameter stenosis worsened

(p = .001)

In the experimental group, 82% of the experimental group patients showed overall regression of coronary atherosclerosis after 1 year9,10 and even more improvement after 5 years than after 1 year.11 In contrast, the degree of coronary atherosclerosis progressed (worsened) in the control group after 1 year and showed even more progression after 5 years. These differences between groups were statistically significant and clinically significant after 1 year and after 5 years.

The number of cardiac events in the experimental group was less than half that in the control group, including significantly lower rates of angioplasty, bypass surgery, and cardiac-related hospitalizations.

Using an a priori score that took into account all four components of the lifestyle intervention, we found a statistically significant, dose-response correlation between adherence to the lifestyle intervention and changes in the degree of coronary atherosclerosis (percent diameter stenosis) across both groups after 1 year and also after 5 years.

We also found a statistically significant, dose-response correlation between intake of dietary fat and changes in percent diameter stenosis as well as a statistically significant, dose-response correlation between intake of dietary cholesterol and changes in percent diameter stenosis.12

Cardiac PET scans revealed that there was an overall improvement in myocardial perfusion (blood flow to the heart) in the experimental group patients after 5 years, whereas control group patients worsened. The size and severity of perfusion defects in the experimental group improved by 4.2 ± 3.8 units, whereas it worsened by 13.5 ± 3.8 units in the randomized control group—a net differences of 400%.13

Lipid-Lowering Medication

None of the experimental group patients in the Lifestyle Heart Trial or the two earlier studies were taking lipid-lowering drugs during these trials. This enabled us to assess the effects of comprehensive lifestyle changes without being confounded by lipid-lowering drug therapy.

Approximately 50% of control group patients began taking lipid-lowering drugs during the study. Progression of coronary atherosclerosis was significantly greater in control group patients who were not talking cholesterol-lowering drugs (40.7% to 59.7%) than those who were (45.7% to 51.7%). There was a 40% average reduction in LDL-cholesterol levels in experimental group patients during the first year even though none of these patients were taking cholesterol-lowering drugs.

Would patients benefit from making comprehensive lifestyle changes and taking cholesterol-lowering drugs? On the one hand, if most patients were able to achieve regression of atherosclerosis without drugs, why add the costs and side-effects? On the other hand, would improvement have been even greater by doing both? To answer this question more research is needed.

Multicenter Lifestyle Demonstration Project

To determine the scalability and cost-effectiveness of this lifestyle medicine program, we conducted the Multicenter Lifestyle Demonstration Project, sponsored by Mutual of Omaha. We were curious to learn whether patients in community hospitals would do as well as in academic medical centers; if patients could safely avoid revascularization; and if cost savings would occur. The data-coordinating center for this study was directed by Alexander Leaf, MD, who at the time was chair of preventive medicine at Harvard Medical School.

Almost 80% of patients who were recommended to undergo revascularization (bypass surgery or angioplasty) chose this lifestyle medicine intervention as a direct alternative and did not have worse clinical outcomes from doing so. Mutual of Omaha calculated saving almost $30,000 per patient in the first year.14

We conducted a second demonstration project in collaboration with Highmark Blue Cross Blue Shield. Through the nonprofit Preventive Medicine Research Institute, we continued to train a total of 53 hospitals and clinics throughout the United States as part of the Multicenter Lifestyle Demonstration Project.15

Almost 3,000 men and women from 24 socioeconomically diverse sites in West Virginia, Nebraska, and Pennsylvania participated in this lifestyle medicine program and data was collected at baseline, 12 weeks, and 1 year. Only 46% of these patients had diagnosed coronary artery disease; 34% had type 2 diabetes; 74% had high blood pressure; 79% had hypercholesterolemia; 69% had obesity.

Again, patients made bigger changes in lifestyle and achieved better clinical outcomes and adherence than had ever been shown in an ambulatory group of patients.16 Overall healthcare costs were reduced by 50% in the first year when compared to a control group matched for age, gender, and disease severity. In the subgroup of these patients who had medical expenses of at least $25,000 in the preceding year, overall healthcare costs were reduced by 400%.

One of the frequent criticisms of preventive medicine from insurance company executives has been that many patients change insurance companies each year. If it takes several years to document cost savings, they may ask, “Why should I pay for a preventive medicine program today when chances are one of my competitors will benefit years later?”

However, since lifestyle medicine is offered as a treatment, not just for prevention, cost savings usually occur during the first year. Thus, lifestyle medicine can be both medically effective and cost-effective, since both clinical outcomes and cost savings occur in the first year.

Intensive Cardiac Rehabilitation (A New Benefit Category)

One of the lessons we learned is that if a lifestyle medicine program is not reimbursable, it is challenging to make it sustainable.

Because of this, we approached the Centers for Medicare and Medicaid Services (CMS) and asked if they would provide Medicare coverage for this lifestyle medicine program. After 16 years of review, CMS created a new benefit category, “intensive cardiac rehabilitation” (ICR), which provides 72 hours of lifestyle training.

Team-Based Care

This is a team approach in which the physician is quarterback and works closely with a team of five other healthcare professionals: a registered nurse, exercise physiologist, stress management specialist (certified yoga/meditation teacher), registered dietitian, and psychologist or psychiatrist.

These 72 hours are allocated into 18 sessions of 4 hours—twice/week for 9 weeks;

  • one hour of supervised exercise, as seen in traditional cardiac rehabilitation programs;

  • one hour of yoga and meditation for stress management;

  • one hour of a support group;

  • one hour lecture with a group meal.

This allows the physician to leverage his or her time by providing supervisory oversight, but most of the training time is offered by the other five healthcare professionals.

After the 72 hours (9 weeks) of training, patients continue to meet in their support groups on their own.

Physicians report that this is a particularly rewarding way to practice medicine and allows them to return to the roots of what usually attracted them to medicine in the first place: the opportunity to empower patients by helping them address the underlying lifestyle causes of coronary heart disease and many other chronic illnesses.

In short, this is a new paradigm of healthcare. Instead of having to see a new patient every 8 to 10 minutes in a managed care practice—in which there is little time to do more than go through problem list, do a quick physical exam, and write a prescription—the physician can oversee a program in which patients receive 72 hours of training. Most of this time is spent with the other five healthcare professionals, allowing the physician to leverage his or her time most productively. We are actively training individual practitioners and teams from hospitals, physician groups, and clinics in this approach to lifestyle medicine.

Other Conditions and Additional Benefits

Although there is a lot of interest in personalized medicine, we found that the same lifestyle changes that can reverse the progression of even severe coronary heart disease may also do so for other chronic conditions.

Prostate Cancer

For example, we conducted the first randomized-controlled trial showing that these comprehensive lifestyle changes may slow, stop, or even reverse the progression of early-stage prostate cancer in men. This provides a third alternative to “watchful waiting”—that is, doing nothing—and seeking conventional treatments with surgery, radiation, and drug treatments in which the vast majority of men do not show any benefit from these conventional treatments yet often experience the side-effects of impotence, incontinence, or both.17

Gene Expression

Also, we found that this program of comprehensive lifestyle changes changed gene expression in men with early-stage prostate cancer. After three months, 501 genes were beneficially affected: up-regulating 48 genes that are protective and down-regulating 453 genes that promote chronic inflammation, oxidative stress, and RAS oncogenes that promote prostate cancer, breast cancer, and colon cancer.18

People often say, “Oh, it’s all in my genes, there’s not much I can do about it.” But knowing that changing lifestyle changes our genes is often very motivating—not to blame, but to empower. Our genes are a predisposition, but our genes are not usually our fate.

Angiogenesis

We also found that comprehensive lifestyle changes inhibit angiogenesis in men with prostate cancer.19 When tumors grow, they often secrete substances such as VEGF that stimulate blood vessels to feed the tumors, since they grow so quickly they may outstrip the normal blood supply. By interfering with this process, tumors may be killed with fewer side-effects than attacking them directly. Drugs like Avastin may accomplish this, but at very high cost and with significant side-effects.

Telomerase and Telomeres

In addition, we found that this program of comprehensive lifestyle changes increased telomerase by 30% in only 3 months.20 Telomerase is an enzyme that repairs and lengthens telomeres, the ends of our chromosomes that regulate aging. As our telomeres become shorter, our lives become shorter and the risk of premature death from a wide variety of chronic diseases increases proportionately. Over a 5-year period, we found, for the first time in a controlled study, that these lifestyle changes lengthened telomeres by approximately 10%, whereas telomeres became shorter in the control group.21 Again, we found a dose-response correlation between adherence to this lifestyle medicine intervention and length of telomeres.

Conclusion

The more mechanisms we study, the greater understanding we have of why comprehensive lifestyle changes can be so beneficial in treating as well as preventing a wide spectrum of chronic diseases and how quickly these benefits can be measured and experienced. And the only side-effects are good ones.

Medical culture and the healthcare system have come a long way since we began doing our research nearly 40 years ago. It is now accepted that heart disease can be reversed with comprehensive lifestyle changes, it is being seen that these same changes have a beneficial effect on many other conditions, a new benefit category called intensive cardiac rehabilitation is now funded by many insurers including the Centers for Medicare and Medicaid Services (CMS), and lifestyle medicine is one of the fastest growing movements in the field of medicine. The increased prevalence of chronic illness has created tremendous financial and social burdens, these positive changes in medicine are creating a new paradigm of healthcare when we need it most.

References

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