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Overcoming Metabolic Syndrome
By Scott Isaacs, Fred Vagnini, Jack Kusler Addicus Books, Inc.
Copyright © 2006 Scott Isaacs, M.D., and Fred Vagnini, M.D.
All rights reserved.
ISBN: 978-1-938803-20-8
CHAPTER 1
Metabolic Syndrome: An Overview
Perhaps you have heard of metabolic syndrome. Or maybe you're like millions of others who have never heard of it. Certainly, it has not been a condition that grabs headlines like diseases such as cancer or coronary heart disease. But still, it's a serious health condition. Without lifestyle changes and treatment, it increases your risk of an early death from a heart attack or a stroke.
How prevalent is metabolic syndrome? It is estimated that 55 million Americans have metabolic syndrome. That's 27 percent of the population. Fortunately, metabolic syndrome is receiving more and more recognition as a serious medical condition, and more health professionals are diagnosing it.
What Is Metabolic Syndrome?
First, the term metabolism refers to the chemical and physical changes that take place within the body and enable its continued growth and functioning. A syndrome is a cluster of symptoms that characterize a specific disease or condition. However, metabolic syndrome is not actually a disease in the usual sense of the word; rather, it is a cluster of disorders. So, it would be technically inaccurate to refer to metabolic syndrome as having symptoms. Accordingly, to define it, we must look at the disorders or components that make up the syndrome.
You may have heard metabolic syndrome also being referred to by other names. It was called syndrome X in the years before the medical community fully understood the condition and the complex relationship between the disorders. It has also been referred to as insulin resistance syndrome, because insulin resistance is a core factor in the development of the condition.
Criteria for Metabolic Syndrome
There is some disagreement in the medical community over what constitutes metabolic syndrome; however, medical experts have established criteria of disorders that one must meet to be diagnosed with metabolic syndrome. Anyone with three or more of the abnormalities listed in the criteria is considered to have the syndrome.
• High fasting blood glucose. This means blood sugar, or glucose levels are high when tested after fasting but are not high enough to be classified as diabetes. High glucose levels are often a sign of insulin resistance, the body's inability to use insulin efficiently.
• Abdominal obesity. Having fat around the belly, or "central obesity," is a key risk factor.
• Low HDL cholesterol. High-density lipoprotein cholesterol, or HDL, is commonly known as the "good" cholesterol.
• High triglycerides. Triglycerides are a form of fat the body uses for energy. The medical term for high triglycerides is hypertriglyceridemia.
• High blood pressure. High blood pressure occurs when the force of blood flowing through the artery walls is too high. High blood pressure is also referred to as hypertension.
This definition, or these criteria, for metabolic syndrome is the most commonly accepted one in medical circles. It was developed by the National Cholesterol Education Program of the National Heart, Lung, and Blood Institute.
Risk Factors for Metabolic Syndrome
• Waist circumference of more then 40 inches for men; 35 inches for women
• Triglycerides levels greater than 150 mg/dL
• Low levels of HDL-C (high-density lipoprotein cholesterol) Men: less than 40 mg/dL; Women: less than 50 mg/dL
• Blood pressure greater than 130/85
• Fasting glucose level greater than 110 mg/dL
The diagnosis of metabolic syndrome is made when three or more of these risk factors are present. Information from the Executive summary of the third report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III).
Other Factors in Metabolic Syndrome
Although having high levels of low-density lipoprotein cholesterol, more commonly called LDL — the "bad" cholesterol — is not among the key criteria for metabolic syndrome, medical experts say it must be taken into consideration. Why? Because it is an "aggravating" factor, in that it increases the risk for heart attack and stroke.
Other conditions may also play a role in the development of the syndrome. One such condition is inflammation in the lining of artery walls, which may be caused by being overweight, having high cholesterol, or having a chronic low-level infection. It appears such inflammation can damage the lining of artery walls and raise a person's risk for heart disease and stroke.
Another factor that may play a role in metabolic syndrome is an increased tendency to form blood clots, a process referred to as [procoagulation. Yet another factor is an impairment in the body's ability to keep naturally occurring blood clots from growing and causing blockages. The medical term for this is impaired fibrinolysis.
Disorders of Metabolic Syndrome Are Interrelated
Part of what makes metabolic syndrome complex is the way in which each of the disorders influences, or "aggravates," the others. For example, insulin resistance can cause abnormal blood fats (cholesterol), high blood pressure, and high blood sugar. Similarly, high blood sugar can cause abnormal cholesterol levels. Another component of the syndrome, excessive belly fat, can result in an increase in blood sugar levels and blood pressure. In the end, the combined effect of these disorders further increases the risk of complications, which can be life threatening.
Who Develops Metabolic Syndrome?
We know that as many as 27 percent of American adults fit the criteria for the syndrome. And some experts believe that 40 percent of adults in their sixties and seventies are affected by the condition; other experts believe that as many as half the population over age sixty have metabolic syndrome.
Perhaps not surprisingly, the incidence of metabolic syndrome is increasing among young people as more and more of the nation's youth become overweight. It's estimated that 6 percent of teens, ages twelve to nineteen, meet the criteria for the syndrome.
Also, the incidence of metabolic syndrome is higher in certain ethnic groups. In the United States, Mexican Americans have a higher incidence of metabolic syndrome. Other groups that have a higher incidence are Latinos, African Americans, Native Americans, Asian Americans, and Pacific Islanders.
What Causes Metabolic Syndrome?
Just as metabolic syndrome is not one specific disease, there is not one specific cause of it. However, many medical experts consider insulin resistance to be the central defect leading to the syndrome. (You'll gain a better understanding of insulin resistance in the next chapter.) At the same time, obesity and physical inactivity play a role in the development of metabolic syndrome. Other metabolic malfunctions are likely caused by a person's genetic makeup. Aging is also a factor — as one ages, one's risk for developing the condition increases.
Can You Overcome Metabolic Syndrome?
Yes, you can. Although the complications from metabolic syndrome can be very serious, even life threatening, being diagnosed with the condition is not a death sentence. The syndrome can be reversed. Two of the most important things you can do are lose weight and increase physical activity. Additionally, medications are available to treat some of the disorders. We will be covering these topics throughout the book.
CHAPTER 2
The Disorders of Metabolic Syndrome: A Closer Look
Every year, metabolic syndrome becomes more of a public health threat. Why? Because it increases the chances of death from cardiovascular disease. Interestingly, deaths from cardiovascular disease have declined over the past fifty years. This is due largely to improved emergency care in our nation's hospitals, as well as to improved clinical care and public health efforts to reduce the risk of disease. However, given the increasing trend toward obesity and metabolic syndrome in the past two decades, the progress in lowering the death rate due to cardiovascular disease could be reversed.
To avoid becoming one of the unfortunate statistics, you should be aware of two key points. The first is understanding the disorders that make up metabolic syndrome. The second is knowing which syndromes affect you and how you can overcome them.
In this chapter, we'll take a closer look at criteria for metabolic syndrome:
• High fasting blood glucose levels
• Abdominal obesity
• Low HDL cholesterol
• High triglycerides
• High blood pressure
Disorder: High Fasting Blood Glucose Levels
It's estimated that 41 million Americans between the ages of 40 and 74 have abnormal blood glucose (sugar) levels. When you have high levels of sugar in your blood, it means your body is not metabolizing sugars adequately. Four outcomes are possible when your blood sugar levels are tested:
• Normal level: Your blood sugar level is in the normal range, meaning your body's insulin is keeping your sugar level under control.
• Impaired fasting glucose: blood sugar values during fasting are above normal but not high enough to be classified as diabetes.
• Impaired glucose tolerance: Blood sugar values are above normal after drinking a sugar solution during a glucose tolerance test but do not meet the criteria for a diagnosis of diabetes.
• Type 2 diabetes: Blood sugar values meet the criteria for diabetes.
From High Blood Sugar to Insulin Resistance
If your doctor tells you that you have high blood sugar, chances are you have been gradually becoming insulin resistant for some time. In fact, the earliest stages of insulin resistance occur many years before a person develops blood sugar problems. To fully understand metabolic syndrome, it is important to understand insulin resistance. In the simplest terms, insulin resistance is a condition in which the body is not able to properly use insulin to move glucose from the blood into cells and convert it to energy.
How Does Insulin Resistance Develop?
Here's how the process works. When you eat, glucose is released into the bloodstream, making your blood sugar level rise. The job of the hormone insulin — which is produced by beta cells in the pancreas — is to move the sugar from the blood into the body's cells to be used for energy. Once that is done, your blood sugar level returns to normal. But when you have insulin resistance, the cells in your body are impaired and are less efficient at using insulin. It is as if your body doesn't recognize the insulin or know how to use it — your body resists the insulin.
When insulin is not efficient at moving glucose into cells for energy, the body tries to compensate by stimulating the pancreas to produce yet more insulin. Eventually, as the body tries to produce more and more insulin to bring blood sugar under control, the beta cells in the pancreas wear out.
This series of actions leads to weight gain. The higher insulin levels stimulate appetite centers in the brain and increase hunger. Furthermore, insulin is a fat storage hormone, so higher insulin levels mean that more of the calories consumed are converted to fat instead of burned as energy. This sets up a vicious cycle of weight gain, increased insulin resistance, higher insulin levels, increased appetite, and more fat storage. The end result is elevated blood sugars, which can lead to type 2 diabetes.
If you have impaired fasting glucose or impaired glucose tolerance, you are said to have "prediabetes." It is important to know this and take actions to reverse it, because prediabetes elevated blood sugar may be nonexistent at first. If the condition is not diagnosed promptly, you will eventually experience symptoms of diabetes — excessive thirst, excessive hunger, frequent urination, and blurred vision.
Causes of Insulin Resistance
Researchers trying to find the causes of insulin resistance have found a variety of problems in the most basic workings of cells. And even though there is much that is still unknown about insulin resistance, the medical community has identified several causes.
• Obesity. This is the most common cause of insulin resistance. Most individuals become insulin resistant when they are 35 to 40 percent above their ideal body weight. Being overweight overloads tissues with excess fatty acids in the blood and promotes insulin resistance.
• Genetics. Your family history is a key factor. In fact, genetics determine at what weight you will develop insulin resistance, rather than whether you will develop it.
• Physical inactivity. A sedentary lifestyle promotes a multitude of metabolic changes that contribute to metabolic syndrome.
• Stress. When the body is stressed, the adrenal glands release a hormone called cortisol. An excess of this hormone is thought to play a part in the development of insulin resistance. Individuals with too much cortisol often develop upper-body fat, which can influence the development of metabolic syndrome. Cortisol also can stimulate appetite and cause weight gain.
• Cigarette smoking. This is known to increase insulin resistance.
• Infection or illness. These may increase or decrease production of hormones key to insulin production and processing.
• Pregnancy. The fluctuation of hormones in pregnancy may influence insulin production and blood sugar levels.
Complications of Insulin Resistance
The complications that can arise out of insulin resistance are essentially the same as those that can result from metabolic syndrome. Any of the complications can be quite serious; however, the combined effect of the disorders intensifies the risk of heart attack or stroke.
Cardiovascular Disease
This is the most serious and most feared complication of metabolic syndrome. It is the number one cause of death in the United States. Cardiovascular disease includes heart attacks and strokes, but any organ can be affected. Cardiovascular disease is a general term that refers to diseases of the heart and blood vessels caused by atherosclerosis. Also referred to as "hardening of the arteries," atherosclerosis is a process by which deposits of cholesterol, called plaques, build up in the arteries. There are several major forms of cardiovascular disease:
• Coronary artery disease, which leads to heart attacks
• Carotid artery disease, which leads to strokes
• Peripheral arterial disease, which is atherosclerosis in the blood vessels of the legs, which can lead to an amputation
• Renal vascular disease, which can lead to kidney failure
Type 2 Diabetes
This is the end stage of insulin resistance, and it occurs when insulin-producing cells in the pancreas are worn out — they finally stop functioning. Many people have insulin resistance for ten years or longer before they know it, and may have diabetes for five years or longer before they are finally diagnosed. Early on, when the body is not able to use insulin adequately (insulin resistance), the pancreas secretes enough additional insulin to overcome the resistance; however, over time the pancreas can become "exhausted," and supply cannot keep up with demand. This is when blood sugar levels rise.
Diabetes can bring about serious complications, including cardiovascular disease. Heart attacks and strokes occur four times as frequently in people with diabetes as in people without diabetes. Diabetes is also the most common cause of kidney failure and blindness in adults. Other potential complications: nerve damage, which may lead to pain and numbness in the hands and feet, and damage to blood vessels, which may result in amputation of limbs. Nerve damage also may cause digestive problems and sexual dysfunction.
Left Ventricular Hypertrophy
This condition is marked by an abnormal thickening of the part of the heart responsible for pumping blood throughout the body. When the heart muscle is overworked, it enlarges, much as your biceps would from lifting weights, but an enlarged, more muscular heart muscle is not healthy. The heart muscle grows in an effort to help the heart do its work; however, over time the thickened muscle actually becomes stiff, loses flexibility, and fails to pump adequate volumes of blood. Left ventricular hypertrophy is best diagnosed with an electrocardiogram (EKG) or an echocardiogram, an ultrasound test of the heart in action. This condition is often treated by controlling high blood pressure.
Obstructive Sleep Apnea
This disorder involves blockage of the airway and is often related to obesity; in the simplest of terms, when a person lies flat, fat tissue can obstruct the airway. The disorder is more likely to occur in men with a neck circumference greater than seventeen inches and in women with a neck circumference greater than sixteen inches.
To an observer, an individual with sleep apnea snores loudly and has episodes in which breathing stops, followed by gasps or snorts when the person is awakened by the apnea. These sleep disruptions result in chronic fatigue. Sleep apnea is linked to heart rhythm disturbances, heart attack and stroke, and sudden death. Sleep apnea is best diagnosed in a sleep laboratory, where electrodes monitor sleeping habits. In-home evaluations are also available but are not always accurate.
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Excerpted from Overcoming Metabolic Syndrome by Scott Isaacs, Fred Vagnini, Jack Kusler. Copyright © 2006 Scott Isaacs, M.D., and Fred Vagnini, M.D.. Excerpted by permission of Addicus Books, Inc..
All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
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