Diabetes, Heart Disease, Prediabetes, Blood Pressure, Hypertension, Metabolic Syndrome, Cholesterol, Triglycerides & PREVENTION
American Heart Association
Most of the food we eat is turned into glucose, or sugar, for our bodies to use for energy. The pancreas, an organ near the stomach, makes a hormone called insulin to help glucose get into our bodies' cells. When you have diabetes, your body doesn't make enough insulin, can't use its own insulin as well as it should, or both. This causes sugars to build up too high in your blood.
Diabetes mellitus is defined as a fasting blood glucose of 126 milligrams per deciliter (mg/dL) or more. "Pre-diabetes" is a condition in which blood glucose levels are higher than normal but not yet diabetic. People with pre-diabetes are at increased risk for developing type 2 diabetes, heart disease and stroke, and have one of these conditions:
- impaired fasting glucose (100 to 125 mg/dL)
- impaired glucose tolerance (fasting glucose less than 126 mg/dL and a glucose level between 140 and 199 mg/dL two hours after taking an oral glucose tolerance test)
Type 2 diabetes is the most common form. It appears most often in middle-aged adults; however, adolescents and young adults are developing type 2 diabetes at an alarming rate. It develops when the body doesn't make enough insulin and doesn't efficiently use the insulin it makes (insulin resistance).
Type 1 diabetes usually occurs in children and young adults. In type 1, the pancreas makes little or no insulin. Without daily injections of insulin, people with type 1 diabetes won't survive.
Both forms of diabetes may be inherited in genes. A family history of diabetes can significantly increase the risk of developing diabetes. Untreated diabetes can lead to many serious medical problems. These include blindness, kidney disease, nerve disease, limb amputations and cardiovascular disease (CVD).
Diabetes is treatable, but even when glucose levels are under control, it greatly increases the risk of heart disease and stroke. In fact, most people with diabetes die of some form of heart or blood vessel disease.
Pre-diabetes and subsequent type 2 diabetes usually result from insulin resistance. When insulin resistance or diabetes occur with other CVD risk factors (such as obesity, high blood pressure, abnormal cholesterol and high triglycerides), the risk of heart disease and stroke rises even more.
When diabetes is detected, a doctor may prescribe changes in eating habits, weight control and exercise programs, and even drugs to keep it in check. It's critical for people with diabetes to have regular check-ups. Work closely with your healthcare provider to manage your diabetes and control any other risk factors. For example, blood pressure for people with diabetes should be lower than 130/80 mm Hg.
AHA Recommendation Diabetes is a major risk factor for stroke and coronary heart disease, which includes heart attack. People with diabetes may avoid or delay heart and blood vessel disease by controlling the other risk factors. It's especially important to control weight and blood cholesterol with a low-saturated-fat, low-cholesterol diet and regular exercise. It's also important to lower high blood pressure and not to smoke.
What is prediabetes?
It's a condition that occurs when the blood glucose (blood sugar) levels are higher than normal but not high enough to be diagnosed as diabetes. lt's also called impaired fasting glucose or impaired glucose tolerance. The American Diabetes Association estimates that 41 million Americans have prediabetes - and most of them will develop type 2 diabetes within the next 10 years.
What does prediabetes have to do with my heart?
Prediabetes can affect the heart in several ways. In fact, long-term damage to the cardiovascular system may occur while a person has prediabetes.
What are my risk factors for prediabetes?
- Family history. If you have a blood relative with diabetes, your risk for developing it is significantly increased. Map out your family history tree online and take it to your doctor to find out what it means for you.
- Race or ethnic background. People of African, Asian, Hispanic and Native American descent have a greater risk of diabetes.
- Being overweight. If you're 20 percent or more over your optimal body weight, you have a higher risk of developing diabetes.
- Hypertension. High blood pressure increases your risk for diabetes.
- Age. The older you are, the higher your risk.
- Alcohol use. Heavy alcohol consumption over time increases your risk.
- Smoking. A person who smokes 16 to 25 cigarettes a day is three times more likely to develop diabetes than a nonsmoker.
- History of gestational diabetes. Developing diabetes during a pregnancy or delivering a baby over 9 lbs. can increase your risk.
How do I know if I have prediabetes?
Prediabetes and diabetes can occur in people of all ages and races, but some groups have a higher risk. This includes African Americans, Latinos, Native Americans and Asian Americans/Pacific Islanders, as well as the elderly.
Prediabetes has no symptoms, so you can have it and not know it. It can only be diagnosed by your healthcare provider using two different tests:
- Fasting Plasma glucose Test (FPG) - This test must be done on an empty stomach, so for eight hours before the test, the person must fast (nothing to eat or drink, except water). A person's plasma is combined with other substances, then from the resulting reaction, the amount of glucose in the plasma is determined.
- A person with prediabetes has a fasting blood glucose level from 100 to 125 mg/dL.
- Oral Glucose Tolerance Test (OGTT) - This test is done to see how well the body handles a standard amount of glucose. It measures the amount of glucose in a person's plasma before and two hours after drinking a large premeasured beverage containing glucose. A doctor can then compare the before and after glucose levels to see how well the body processed the sugar.
- A person with prediabetes will have a blood glucose level between 140 and 199 mg/dL two hours after the premeasured drink
The U.S. Department of Health and Human Services recommends that everyone who is overweight and older than 45 be tested for prediabetes. However, if you're younger than 45, overweight and have one or more other risk factors, such as high blood pressure, high cholesterol or are in one of the high risk groups listed above, testing is still appropriate. If your blood glucose levels are in normal range, then testing should be done about every 3 years. If you have prediabetes, you should be checked for diabetes every 1-2 years after diagnosis.
What can I do to prevent prediabetes?
Physical inactivity and overweight/obesity are the most important modifiable risk factors for prediabetes. Exercising 30 minutes a day and losing 5 percent to 7 percent of your body weight (about 10 pounds for a 200-lb. person) can lower your risk by half. And your risk continues to decrease as you lose even more weight. Increasing physical activity and eating a heart-healthy diet can also help you lose weight and lower your risk of diabetes, and heart and circulatory illnesses.
Talk to your doctor about how to change your eating and physical activity habits to reduce your chances of developing diabetes.
Diabetes and Cardiovascular Disease
Cardiovascular disease is the leading cause of diabetes-related death. People with diabetes are two to four times more likely to develop cardiovascular disease due to a variety of risk factors, including
- high blood pressure
- lipid disorders
- high LDL bad cholesterol
- high triglycerides
- low HDL good cholesterol
- lack of physical activity
Another emerging risk factor is insulin resistance, a core metabolic dysfunction of type 2 diabetes. Insulin resistance is a condition where the body doesn't respond efficiently to the insulin it makes. According to Gene Therapy Weekly, it affects about 60 million people in the United States. One in four of them will develop type 2 diabetes when their body becomes unable to maintain normal insulin and glucose levels.
Following is a list of conditions typically found in people with type 2 diabetes, and an explanation of how they contribute to a patient's risk for developing cardiovascular disease.
Obesity is a major risk factor for cardiovascular disease and has been strongly associated with insulin resistance. Insulin resistance may be a mechanism by which obesity leads to cardiovascular disease. Weight loss has been shown to improve cardiovascular risk, decrease insulin concentration and increase insulin sensitivity. Obesity and insulin resistance also have been shown to be associated with other risk factors, such as high blood pressure. Learn how to manage your weight.
- Physical Inactivity
Physical inactivity is another modifiable major risk factor for insulin resistance and cardiovascular disease. Exercising and losing weight have been shown to prevent or delay the onset of type 2 diabetes, reduce blood pressure and help to reduce the risk for heart attack and stroke. It's likely that any type of physical activity - whether sports, household work, gardening or work-related physical activity - is similarly beneficial. Join our 12 week physical activity program today.
Hypertension (high blood pressure), has long been recognized as a major risk factor for cardiovascular disease. Studies report a positive association between hypertension and insulin resistance. When a person has both hypertension and diabetes, a common combination, their risk for cardiovascular disease doubles. Learn more.
Atherogenic dyslipidemia, often called diabetic dyslipidemia in people with diabetes, is a condition associated with insulin resistance. This type of dyslipidemia is characterized by high levels of triglycerides (hypertriglyceridemia), high levels of small LDL particles and low levels of HDL. This lipid triad often occurs in patients with premature coronary heart disease.
Growing evidence suggests that all of the components of the lipid triad can contribute to the development of atherosclerosis (fatty-buildups in artery walls) and can be considered as a risk factor. Even though most patients with diabetes don't have marked elevations of LDL cholesterol, their levels are high enough to support the development of atherosclerosis. Learn more about diabetes and cholesterol
Disease process associated with insulin resistance and diabetes
Atherosclerosis is a process that can start early in life. It often progresses when people grow older, which leads to coronary heart disease, a type of cardiovascular disease. It begins with damage in the endothelium (inner layer of the artery) followed by plaque build-up. It may stimulate the artery wall cells to produce other substances that result in further build-up of plaque. These cells and surrounding material significantly thicken the endothelium. When the plaque ruptures, a blood clot forms and blocks the artery, stopping the blood flow. Proven causes of damage to the arterial wall are elevated levels of cholesterol and triglycerides, high blood pressure and tobacco smoke.
Cardiovascular risk factors such as obesity, physical inactivity, abnormal blood lipid pattern, hypertension and smoking predispose a person to atherosclerosis. Evidence also suggests that insulin resistance itself, independent of other risk factors, could be a major determinant of atherosclerosis.
Diabetes and High Blood Pressure
Controlling blood pressure in people with diabetes is especially important because high blood pressure is a major risk factor for cardiovascular disease and increases the risk for heart attack, stroke and other complications such as retinopathy (damage to blood vessels in the retina) and nephropathy (damage to blood vessels in the kidneys).
What is blood pressure?
Blood pressure is the force of blood against the arteries when the heart beats (systolic pressure) and rests (diastolic pressure). It's measured in millimeters of mercury (mm Hg). Learn more about how high blood pressure develops and its causes.
What's normal blood pressure?
American Heart Association recommendations:
How do I know if I have high blood pressure?
You probably won't. Even when your blood pressure is chronically high, you won't have symptoms. In fact, many people have this disease for years without knowing it.
Many people falsely believe that high blood pressure has to do with being tense, nervous or hyperactive. You can be a calm, relaxed person and still have high blood pressure.
The only way to find out if you have it is to have your blood pressure checked! A blood pressure test is quick and painless. It can be done in a doctor's office, hospital clinic, school, nurse's office, company clinic or at a health fair. Learn more about how blood pressure is checked.
Why is it important to treat high blood pressure?
High blood pressure increases the risk of coronary heart disease (which leads to heart attack) and stroke, especially when it's present with other risk factors, such as diabetes. When a person has high blood pressure and diabetes, a common combination, their risk for cardiovascular disease doubles.
What can I do?
There's no cure for high blood pressure. But it can be controlled. If you have diabetes and high blood pressure, work with your physician to get your blood pressure below 130/80. Weight control, regular physical activity and diet help lower blood pressure and manage cholesterol and glycemia (the presence of glucose in the blood). When you talk to your healthcare provider, he or she may discuss several options for treatment including:
- Losing weight if you're overweight.
- Eating a healthy diet low in saturated fat, cholesterol and salt.
- Being more physically active.
- Limiting alcohol to no more than one drink per day for women or two drinks a day for men.
- Taking medications. Learn more about how blood pressure medications work.
In recent years use of the term metabolic syndrome has become more common. What is the metabolic syndrome and what does it have to do with diabetes?
Metabolic syndrome is when a person has a group of metabolic risk factors including:
- Central obesity - (excessive fat tissue in and around the abdomen)
- Blood fat disorders (Atherogenic dyslipidemia) - mainly high triglycerides and low HDL cholesterol that foster plaque buildups in artery walls
- Insulin resistance or glucose intolerance (the body can't properly use insulin or blood sugar)
- Prothrombotic state (e.g., high fibrinogen or plasminogen activator inhibitor [-1] in the blood)
- Raised blood pressure (130/85 mmHg or higher)
- Proinflammatory state (e.g., elevated high-sensitivity C-reactive protein in the blood)
The underlying causes of metabolic syndrome are overweight/obesity, physical inactivity and genetic factors. People with metabolic syndrome are at increased risk of coronary heart disease, other diseases related to plaque buildups in artery walls (e.g., stroke and peripheral vascular disease) and type 2 diabetes.
Who has metabolic syndrome?
The metabolic syndrome has become increasingly common in the United States. It's estimated that about 20-25 percent of US adults have it.
Obesity and insulin resistance are two potential and important causes of the metabolic syndrome. Abdominal or central obesity (increased waist circumference) is the form of obesity strongly associated with the metabolic syndrome. However, the mechanisms underlying the association between abdominal obesity and the metabolic syndrome are not fully understood and likely are complex. The syndrome is also closely associated with a generalized metabolic disorder called insulin resistance, in which the body can't use insulin efficiently. Some people are genetically predisposed to insulin resistance. Acquired factors, such as excess body fat and physical inactivity, can elicit insulin resistance and the metabolic syndrome in these people. Most people with insulin resistance have central obesity. The biologic mechanisms at the molecular level between insulin resistance and metabolic risk factors aren't fully understood and appear to be complex.
How is the metabolic syndrome diagnosed?
There are no well-accepted criteria for diagnosing the metabolic syndrome. The criteria proposed by 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) are the most current and widely used.
According to the ATP III criteria, the metabolic syndrome is identified by the presence of three or more of these components:
- Central obesity as measured by waist circumference:
Men - Greater than 40 inches
Women - Greater than 35 inches
- Fasting blood triglycerides greater than or equal to 150 mg/dL
- Blood HDL cholesterol:
Men - Less than 40 mg/dL
Women - Less than 50 mg/dL
- Blood pressure greater than or equal to 130/85 mmHg
- Fasting glucose greater than or equal to 100 mg/dL
The ATP III panel did not find evidence to recommend routine measurement of insulin resistance (e.g., increased fasting blood insulin), prothrombotic state or proinflammatory state.
More studies are needed to understand the relationship between metabolic risk factors and the efficacy of drug therapy in people who have the metabolic syndrome.
Lifestyle interventions deserve prime consideration for cardiovascular risk reduction; these include weight control, increased physical activity, and a diet designed to reduce risk for cardiovascular disease.
Other steps for managing the metabolic syndrome are also important for patients and their doctors:
Routinely monitor body weight (especially the index for central obesity), blood glucose, lipoproteins and blood pressure. Treat individual risk factors (hyperlipidemia, hypertension and high blood glucose) according to established guidelines. Carefully choose anti-hypertensive drugs because different agents have different effects on insulin sensitivity.
Diabetes and Cholesterol
Getting down to the details
If you have diabetes, you're more likely to have more cholesterol abnormalities - which contributes to cardiovascular disease. Managing your cholesterol, and especially lowering LDL cholesterol, reduces your chance of cardiovascular disease and death. In fact, a person with diabetes who lowers his LDL cholesterol can reduce the risk of having a heart attack by up to 42 percent.
How do I know my cholesterol numbers?
A lipid profile is a measure of different kinds of fats in your blood. Your healthcare provider determines your lipid profile based on your total cholesterol, LDL ("bad") cholesterol, HDL ("good") cholesterol and triglyceride (blood fats) levels
What is cholesterol?
Cholesterol is a waxy substance in your blood that your liver makes. It's also found in foods from animals, such as egg yolks, meat, fish, poultry and whole-milk dairy products. Your body uses cholesterol to make hormones and build cell membranes and other needed tissues. But if too much LDL cholesterol circulates in the bloodstream, it can build up in the inner walls of the arteries and lead to fatty deposits of plaque called atherosclerosis. Learn More
Cholesterol goals for people with diabetes
People with diabetes have the same risk for heart disease and stroke as people who already have cardiovascular disease. So their target levels for LDL cholesterol are lower.
- Low-density-lipoprotein (LDL) cholesterol is called "bad" cholesterol. When too much LDL cholesterol is in your blood, it may be deposited in the inner walls of your arteries. Together with other substances, it can form plaque and cause your risk of heart disease to increase. So keep your LDL cholesterol level below 100 mg/dL. In some cases, if you have other cardiovascular risk factors, your healthcare provider may want your level to be below 70 mg/dL.
- High-density-lipoprotein (HDL) cholesterol is called "good" cholesterol. HDL cholesterol has the opposite effect of LDL cholesterol. HDL removes cholesterol from the blood. Your HDL cholesterol levels should not be below 40 mg/dL (the higher the better). An HDL cholesterol of 60 mg/dL and above is considered protective against heart disease.
- Triglycerides are the main form in which fats exist in the body. Triglycerides come from fats eaten in foods or are made in the body by the liver. A high triglyceride level contributes to atherosclerosis. Ideally, you want to maintain triglycerides below 150 mg/dL.
How diabetes affects cholesterol
Diabetes tends to lower "good" cholesterol and raise triglyceride and "bad" cholesterol levels, which increases the risk for heart disease and stroke. This common condition is called diabetic dyslipidemia.
"Diabetic dyslipidemia means your lipid profile is going in the wrong direction. It's a deadly combination that puts patients at risk for premature coronary heart disease and atherosclerosis - where the arteries become clogged with accumulated fat and other substances," said Richard Nesto, M.D., a spokesperson for the American Heart Association.
Studies also show a link between diabetic dyslipidemia and insulin resistance, a precursor to type 2 diabetes. If you have insulin resistance (nine out of 10 people with diabetes do), your body doesn't respond efficiently to the insulin it produces.
Avoiding Cholesterol's Bad Side
Now that you know about cholesterol, you can take steps to control it:
- Have your cholesterol checked regularly.
- Talk to your doctor about the best plan for you.
- Eat a diet low in saturated fat, trans fat and cholesterol.
- Exercise regularly. Physical activity helps increase your HDL "good" cholesterol.
Some people may also need to take cholesterol-lowering medications. Ask your doctor about the effects your diabetes medication may have on your cholesterol, since some may improve your lipid profile. Learn more about cholesterol medications.