What Doctors Know about Diabetes
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TABLE OF CONTENTS Preface ........................................................................................................ 1 Background Information and Statistics on Diabetes ................................... 5 The Basic Statistics regarding Diabetes ..................................................... 10 Things to Remember from this Section ......................................................................... 14
Normal Anatomy and Physiology .............................................................. 15 Carbohydrate Digestive Issues ...................................................................................... 15 The Pancreas and its Role .............................................................................................. 18 Exercise and Blood Sugar .............................................................................................. 23 Things to Remember from this Section ......................................................................... 25
Pathology and Pathophysiology of Diabetes .............................................. 26 Type 1 Diabetes Pathophysiology .................................................................................. 26 Type 2 Diabetes Pathophysiology .................................................................................. 29
Polycystic Ovarian Disease and Diabetes ........................................................... 33 Gestational Diabetes Pathophysiology .......................................................................... 34 MODY Pathophysiology ................................................................................................. 35 Latent Autoimmune Diabetes ........................................................................................ 36 Miscellaneous Causes of Diabetes ................................................................................. 37 Things to Remember from this Section ......................................................................... 38
Symptoms of Diabetes ............................................................................... 39 Things to Remember from this Section ......................................................................... 43
Complications and their Management ....................................................... 44 Acute Complications of Diabetes ................................................................................... 44
Management of Diabetes and Heart Failure ................................................................. 93 Pancreas Transplants ..................................................................................................... 95 Important Things to Remember from this Section ....................................................... 98
Living with Diabetes ............................................................................... 100 Maintaining a Normal Weight ..................................................................................... 100 Dietary Measures: Understanding the Glycemic Index .............................................. 105 The Plate Method .......................................................................................................... 1 11 The Mediterranean Diet................................................................................................ 112 The DASH Diet .............................................................................................................. 114 Exercise and Diabetic Control ...................................................................................... 118 Managing Blood Sugars on a Day-to-Day Basis .......................................................... 122 Continuous Glucose Monitoring or CGM .................................................................... 125 Treating Diabetes with an Insulin Pump ......................................................................127 Managing Complications of Diabetes .......................................................................... 130 Things to Remember from this Section ........................................................................ 137
Current Research on Diabetes ................................................................. 139 Things to Remember from this Section ....................................................................... 150
The Future ............................................................................................... 151 Things to Remember from this Section ....................................................................... 154
Summary ................................................................................................. 155
PREFACE Diabetes mellitus or diabetes is not just a disease some other person has in America or in the world, for that matter. It is a true epidemic with an incidence in our population that is increasing every day. According to the Diabetes Research Institute, more than 9 percent of us in the United States have diabetes but only 7 percent actually know they have it. It affects adults and children alike and is a major cause of death and disability
in the western world. Diabetes is not just a single disease but, in fact, represents several different conditions that all lead to the same health issues. It is considered a metabolic disease because it affects the metabolism of every cell in your body. Regardless of its underlying cause, all people with diabetes have the end result of having high blood sugar, which means that there are high levels of glucose, the major simple sugar in human cells and tissues, all
throughout the body. Basically, diabetes is a problem where, for several reasons, the insulin in the body, which is the hormone your pancreas produces in response to eating a meal containing sugar, fails to put this sugar into your cells, where it is supposed to be used to provide essential nutrition to the cells. This is a big problem because, regardless of the content of the meal, every nutrient you eat ultimately must be chemically transformed into sugar
for the cell to work properly. If there isn’t enough of this insulin hormone or if it doesn’t work properly, sugar or glucose will not enter the cells and the cells essentially starve, even though there is plenty of glucose available outside the cells. In fact, there is altogether too much glucose everywhere else in your body, which is a source of other problems a diabetic has. Your
blood vessels and nerves do not like so much glucose around so they become damaged—
and sometimes permanently or irreversibly. As you will see in this audiobook, diabetes is usually not a problem of a lack of insulin in
the body nor does it mean the diabetic must take insulin shots for the rest of their lives. Yes, a few people with diabetes have this issue but most do not. Instead, if you could
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measure the actual insulin levels in the bloodstream of most diabetics, which is rarely actually done, you would find the insulin level to be too high. How could this actually lead to the same problem of high blood sugar as is the case with diabetics who have no
insulin at all? As it turns out, diabetes is much more complicated than just a lack of insulin. Some diabetics really do not have enough of this hormone, while many others have an altogether different problem that leads to the same result. They instead have what’s called “insulin resistance”, which means that it really doesn’t matter how much insulin there is, the cells of the body do not respond properly to it so the blood sugar rises outside the cells and the cells themselves still starve from a lack of available sugar inside
the cell. In this audiobook, we will talk about the different kinds of diabetes and why they occur. You should know now, however, that most diabetics are not just suffering from a random disease they inherited or were unlucky enough to catch. Diabetes is essentially a lifestyle disease that only partly has to do with genetics or bad luck. With a lifestyle disease like diabetes, the problem is mostly because of things we do or don’t do in our
lives that contribute to getting the disease. You’ll also find out that diabetes really isn’t a problem of “eating too much sugar”, although that can play a role in the diabetic’s life. It has far more to do with being obese or overweight than anything else. Yes, it basically comes down to the simple problem facing most Americans today and that is that we, as a population, are much too fat. We eat too many calories every day, we eat the wrong foods, and we don’t get enough exercise. This leads to an unhealthy buildup of fat that, for several reasons, leads to this
problem of insulin resistance that underlies most cases of diabetes mellitus. While doctors are learning more about diabetes every day and while there have been many positive research findings that have helped improved the lives of diabetics compared to how things used to be even a few decades ago, they have not yet found anything even close to a cure for this disease. In fact, this may never actually happen because it is nearly impossible to cure what is essentially something related directly to
our day-to-day behaviors.
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Perhaps the best things doctors have come to learn about most cases of diabetes is who is most at risk for this disease, what things contribute greater to getting it in the highrisk person, what can be done to prevent the disease in the first place, and which new treatments work best to treat the underlying problem of insulin resistance in the
diabetic patient. For those diabetics who truly don’t have enough insulin in their bodies, great strides have been made in how best to regulate blood sugars in these patients, including efforts made by researchers in organ transplant surgery to replace defective pancreatic tissue with transplanted pancreases that can finally make the missing insulin hormone. For these patients, it can be said that their diabetes is effectively cured but, of course, organ
transplantation by itself is a risky procedure and is not for everyone. We will also talk quite a bit about the complications of diabetes, which can happen in anyone with the disease, regardless of what the underlying cause is. While some people
can die from having high blood sugar by itself, this is rarely the case for most people. Diabetes is a really bad disease, even if you never suffer from the immediate effects of high blood sugar. The biggest problem with diabetes is instead the chronic complications of having high blood sugars in the body over several years. You’ll learn about what happens when high blood sugar is allowed to happen in your body over a long period of time. It damages the nerves of the body, leading to several kinds of related nerve diseases. It destroys the small blood vessels in the body, which makes diabetes a major cause of blindness, kidney disease, and worsened nervous system disease—mostly due to poor circulation to the eyes, kidneys, and nerves. Worse yet, diabetes damages the large vessels of the body, such as those that supply blood to the heart, brain, and extremities. The end result of this complication is stroke, heart
attacks, and amputations of the legs from poor circulation, infection, and gangrene. Hopefully, though, what you’ll get most out of this audiobook is the fact that having diabetes or being at risk for it is not just a matter of helplessness and hopelessness. Many diabetics live long and healthy lives, mostly because they have come to recognize
what needs to be done in order to prevent its devastating complications.
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The person lucky enough to know they are at risk for diabetes but who do not yet have it can actually find ways to avoid getting it altogether, although it often takes a commitment to a different lifestyle—one that is necessary to stop the metabolic processes happening in the body that will ultimately lead to developing diabetes and to the complications that necessarily arise from having it. If this is you, you should listen even more carefully to everything you hear in this audiobook. Ultimately, the choices
you make with regard to your lifestyle will affect your life forever.
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BACKGROUND INFORMATION AND STATISTICS ON DIABETES The simple answer to the question of “what is diabetes” is that it means having high blood sugar or, more specifically, high blood glucose levels in the bloodstream. As you’ll find out, there are several types of sugar you can eat. Fructose, for example, is often called fruit sugar, because this is one of the main simple sugars in fruits. Lactose is generally called milk sugar because this is the sugar you’ll find in milk and other dairy products. Sucrose is table sugar, which is the kind found in most baked sweets and in
the sugar you spoon into your coffee. Regardless of the type of sugar you consume, all of it ultimately gets chemically
transformed into glucose, which is the sugar all of your cells exclusively use as part of their metabolism. Even the fat you and the protein you take in get funneled into the same metabolic pathways within the cell used to make cellular energy. That’s the real goal of cellular metabolism—to provide the necessary nutrients so that the cell can get
the energy necessary to run all cellular processes. Diabetics basically have too much sugar in their bloodstream and in the tissue spaces between the cells and not enough in the cells themselves. This is very bad for the cells, which must then rely on other types of nutrients to make cellular energy in chemical processes that simply aren’t as efficient as they would be if glucose itself was available to the cell instead. This is why some diabetics who haven’t yet been treated sometimes lose weight even though they’ve eaten enough. The body chooses to eat its own tissues in
order to survive because the cells won’t be able to use the available glucose. As we’ve already discussed, there are different types of diabetes that lead to the same high blood sugar problem. We’ll talk more about these later but, for now, let’s summarize the different types, including how they occur and why they cause high blood
sugar. Type 1 diabetes is sometimes called juvenile diabetes because it mainly happens in young people, although it can happen in the older person less commonly. About 1.25
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million people in the United States have this type of diabetes. Type 1 diabetes is partly hereditary and partly an environmental problem that isn’t completely understood. The type 1 diabetic develops autoantibodies, which are immune-related proteins directed at the cells of the human pancreas that are responsible for making the insulin hormone. Insulin is crucial to blood sugar metabolism in the body. It is mainly through the pancreatic release of insulin in response to higher blood glucose levels that this sugar gets into the cells in the first place. In type 1 diabetics, insulin is no longer made because the pancreatic cells responsible for making it are permanently destroyed by the immune system. No drug or treatment besides giving the person insulin directly will help these people. This is a lifelong problem because the pancreatic cells do not
regenerate themselves. The disease is manageable but not usually curable. Most people with diabetes, however, have type 2 diabetes. Compared to the 1.25 million people with type 1 diabetes, more than 30 million people in the US have type 2 diabetes. This is between 90 and 95 percent of all diabetics. While it has traditionally been a disease of older persons, it is increasingly being seen in children, teens, and younger
adults—mostly because of the epidemic of obesity in our country. These are the people who have insulin resistance. For reasons we will talk about later, the cells themselves do not respond to insulin the way they are supposed to and glucose still doesn’t get into the cells. The pancreas responds to this problem by putting out even more insulin, which still doesn’t help much. High levels of insulin by itself are harmful to you, as you will see. Eventually, type 2 diabetics who aren’t treated essentially become type 1 diabetics, mainly because the pancreas simply burns out and can’t make insulin anymore. These patients also eventually need insulin. Take a look at figure 1 to see the basic difference between type 1 and type 2 disease:
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Figure 1.
We will also talk about the complicated issue of a condition called prediabetes. Prediabetes is a true epidemic, affecting 84 million Americans or just about a third of every one of adults in the US. The most difficult part of this problem is that 90 percent of prediabetics don’t know they have it. The second most difficult part is that, for those who know they have it, not enough is done to keep prediabetes from becoming true type
2 diabetes.
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Prediabetes can be considered a “wake-up” call for everyone who has it. As you’ll see, this can be tested for in the doctor’s office and, when intervened on, it can mean the difference between remaining healthy and becoming diabetic. Prediabetes is a precursor disease to type 2 diabetes but not type 1 diabetes. There is probably nothing magical that defines whether you have type 2 diabetes versus prediabetes except that the
blood sugar numbers are not as bad in prediabetes as they are in type 2 diabetes itself. In fact, it might be argued that these two diseases are part of a long spectrum that goes from being healthy, through having prediabetes, and to finally having type 2 diabetes. The main problem in prediabetes is the same one as with type 2 diabetes and that is insulin resistance. The main difference, however, is that, in prediabetics, the insulin being produced by the pancreas is effectively keeping up with the blood sugar problem so the blood sugars aren’t so bad. In fact, some prediabetics occasionally have the opposite problem of too low blood sugar after a high carb diet. The insulin overreacts temporarily to the sugar load and drives the blood sugar downward, leaving the person
with temporary symptoms of low blood sugar. Some women will have what’s called gestational diabetes, which is diabetes that only occurs in the last part of pregnancy, sometimes leading to birth complications, including stillbirth and having an infant that is too large to fit through the birth canal. About 6 to 9 percent of all pregnancies are complicated by gestational diabetes. This involves so many pregnancies that this is tested for in every pregnant woman sometime during the pregnancy in order to intervene on those who test positive for the disease. Part of the problem is that pregnancy itself is a temporary state of insulin resistance in every women but only some of them have this issue bad enough to be called gestational diabetes or to require treatment. In most cases, the high blood sugar conditions during the pregnancy go away after the delivery of the baby but it can come back with subsequent pregnancies. Women with gestational diabetes also have a higher risk of
later developing type 2 diabetes unrelated to being pregnant. There are less common types of diabetes that most people have never heard of that are
largely hereditary. Maturity Onset Diabetes of the Young or MODY is one of them, though it sometimes goes by other names. It involves a genetic defect in one of eleven
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known genes that control glucose metabolism in the body through different mechanisms. Up to five percent of all diabetics have MODY rather than type 2 or type 1 diabetes. Many don’t know they have this form but most will recognize that diabetes
exists in many members of their immediate family. You do not have to be overweight or obese to have MODY and many develop what they think is type 2 diabetes but at a younger than expected age. Most of these are called autosomal dominant inherited diseases, which means that the affected person has a fifty-fifty chance of passing it onto each of their children. This adds up to having people with diabetes in every generation for the most part and to a lot of people in the family
who seem unlucky enough to be diabetic. Some people with MODY require pills or other medications to control their high blood sugar, while others need some form of insulin therapy to manage their condition. Of all types of diabetes, MODY is probably the least understood and the hardest to identify, although newer genetic tests have become available to diagnose those who have it early
in the course of the disease process.
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THE BASIC STATISTICS REGARDING DIABETES Just how big a problem is diabetes in the United States and probably in other developed countries as well? It’s a huge problem, as you might be discovering in this audiobook already, and it is a problem that is increasing in incidence as the people in our nations become fatter and more sedentary. More than seven million people alone out of the 30 million people total do not even know they have it, even though they are at just as great
a risk for complications as those who know they have it. About a fourth of all people over the age of 65 years have diabetes. Almost all of these have type 2 diabetes, partly because type 1 diabetics often don’t even live that long unless they are aggressively treated. More than 1.5 million new cases of diabetes are identified in the United States each year, mostly because of testing done at the doctor’s
office when they have no symptoms of the disease. Diabetes is considered the seventh leading cause of death in the United States, although this number is probably artificially low because patients with diabetes often die of diabetic-induced complications listed on their death certificate as the main cause of death without diabetes being mentioned on the death certificate. In 2015 alone, researchers identified nearly 80,000 death certificates listing diabetes as the major cause of death. Three times as many or about 250,000 death certificates included diabetes as a factor that contributed to the person’s death. As we’ve already mentioned, diabetes is a risk factor for other diseases that are more deadly than dying from high
blood sugar by itself. Young people have a chance of either type of diabetes. About 190,000 people under the age of 20 in the United States have known diabetes, which is only one-fourth of one percent of young people. That number, however, is expected to rise in the coming years—not because the incidence of type 1 diabetes is going up but because of higher numbers of type 2 diabetics being discovered. Just ten years ago, about 17,900 juveniles
in America had type 1 diabetes, while 5300 had type 2 diabetes.
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Only 5300 young people with type 2 diabetes doesn’t sound like many but, in a 2012 research study published in the American Diabetes Association journal called Diabetes Care, these numbers probably represent just the beginning of the epidemic of type 2 diabetes. In the study, they estimated that the number of diabetes cases in young people could be up to 50 percent higher than they are now by the year 2050, and that’s only if the rise in incidence stays the same. If the rate of increase worsens, the number of cases
could go up fourfold during that same time period. As you will later learn, the risk of developing type 2 diabetes depends on what your race
or ethnicity is. This is based on hereditary factors that are not completely understood. Non-Hispanic whites have diabetes at a rate of about 7.4 percent, with Asians, especially Filipinos, having a slightly higher risk. The risk goes up to more than 12 percent in Hispanics and in non-Hispanic blacks. Mexican-Americans have a higher risk than other Hispanic ethnicities. Among Hawaiians, 41 percent have prediabetes and 13 percent have type 2 diabetes. American Indians and Alaskan Natives have the highest
risk of all, with diabetes found in more than 15 percent of the population. As a disease, diabetes is very costly in ways unrelated to death from the disease itself. A
March 2018 study by the American Diabetes Association indicated that the total costs of diabetes in the United States is about $327 billion dollars. This compares with costs just five years earlier of just $245 billion dollars per year or about a 26 percent increase in
total monetary burden of this disease. Some of these costs are related to the direct costs of managing the disease and its complications, estimated to be about $237 billion dollars per year. Other costs are harder to measure but represent the costs related to reduced productivity, which is the dollars lost by people and the community in general when the diabetic can no longer work to support themselves due to illness or disease complications. This is believed to
be about $90 billion dollars a year. Diabetics are hospitalized more often than the general population, accounting for 30 percent of the total direct medical costs of the disease. Prescriptions alone used to treat just the complications of diabetes are responsible for another 30 percent of the total costs incurred. Diabetic supplies and other anti-diabetic treatments add up to 15
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percent of the cost and visits to the doctor in order to manage diabetes add up to 13
percent of the total cost. For the person with diabetes, this means spending about $17,000 dollars a year for medical treatment, more than half of which is directly related to having diabetes. This is more than double what the person without diabetes has to pay for their treatment each
year. Of course, the diabetic alone doesn’t only pay this price. When the insurance companies, Medicare, and Medicaid are responsible for these high costs, the real cost is everyone’s problem because it means higher taxes, higher insurance premiums, and a higher economic burden for the entire country. If 25 percent of all healthcare dollars are spent on diabetes in the US, which is the current estimate, you can bet that everyone in
the country pays some of these costs. Indirect costs due to diabetes are related to several things. Diabetics in the workforce miss work more often than those who do not have diabetes, accounting for billions of dollars lost. Even when they work, their productivity is lower, which is also costly to everyone. Those who cannot work at all often receive some type of disability benefit from the government and do not contribute to the overall productivity of the country in general. Finally, there are the losses incurred when a diabetic dies prematurely, leaving their family without the necessary income to support themselves and, again, everyone
pays the price. In fact, more than two-thirds of all of the cost for diabetic care comes directly from the US government, which includes programs like Medicaid, Medicare, and military health programs. The remainder is paid for through private insurance companies. Those who have diabetes but no insurance coverage see the doctor less often and take fewer medications for their diabetes but have 168 percent more visits to the emergency department for complications than those who do have health insurance. States like California, Texas, Florida, and New York bear the greatest financial burden of this
disease. To summarize this section of the audiobook, it is probably safe to conclude that diabetes mellitus is just an umbrella term for a number of related metabolic diseases and that it
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is a serious disease, costing this country and others billions of dollars per year in direct and indirect costs related to having it. Its incidence in the US is increasing and the burden to our economy and collective health will only increase further unless something
is done to reduce the risks of developing it.
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THINGS TO REMEMBER FROM THIS SECTION •
There are several types of diabetes, affecting about 30 million Americans.
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Type 1 diabetes is an autoimmune disease that destroys the ability of the pancreas
to make insulin.
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Type 2 diabetes represents up to 95 percent of all cases;
is related to insulin
resistance and to an inability of the cells to respond to existing insulin levels in
the bloodstream.
•
Type 2 diabetes is partly genetic and partly related to lifestyle; certain ethnicities are at a higher risk of developing the disease.
•
Gestational diabetes is diabetes that occurs only in pregnancy and is related
somehow to having insulin resistance during this time.
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MODY or Maturity Onset Diabetes of the Young is a genetic cause of diabetes related to gene defects that affect half of all of the affected person’s children later
in their life. •
Diabetes is the seventh leading cause of death officially but this number is probably inaccurate because diabetes is the underlying risk factor for other
diseases a person can die from. •
Diabetes is very costly, both in the direct costs of treating the disease and in the indirect costs related to lost work productivity, disability, and premature death
from having diabetes.
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