Several factors may contribute to a person’s developing insulin resistance. These include a genetic risk (especially if a family member has type 2 diabetes); having insulin receptor mutations (called Donohue syndrome); and being African American, Hispanic, American Indian, or Asian. Other risk factors include being between the ages of 40 and 45, being obese, having a sedentary lifestyle, high triglyceride levels, hypertension, pre-diabetes, having had gestational diabetes (and having a baby who was more than nine pounds [four kilograms] at birth), and where a person stores fat (especially if the fat is mostly in the abdomen rather than in the hips and thighs).
What is one way that may help lower the risk of developing insulin resistance that could lead to type 2 diabetes?
Similar to what most doctors recommend for any type of diabetes, two of the best ways to lower the risk of developing insulin resistance are exercise and weight loss.
TYPE 2 DIABETES AND THE METABOLIC SYNDROME
What is metabolic syndrome and its connection to diabetes?
Metabolic syndrome (once called Syndrome X) is a cluster of metabolic risk factors that a person has, all putting the person at risk for various diseases. One of the major traits of metabolic syndrome is obesity, or being overweight, either through poor eating habits, not enough exercise, or other factors. Found mostly in adults (many with prediabetes), obesity includes too much fat around the waist (in other words, a large waist measurement), high blood pressure, high triglycerides, and abnormal blood fats (especially certain cholesterol levels).
In terms of diabetes, metabolic syndrome also includes high blood glucose levels, which go hand-in-hand with glucose intolerance. Not only does metabolic syndrome predict an increased risk of diabetes, it also predicts cardiovascular disease. (For more about cardiovascular disease, see the chapter “How Diabetes Affects the Circulatory System.”)
How many people are estimated to have metabolic syndrome in the United States?
It is estimated that about 34 percent of adults in the United States have metabolic syndrome. It is found to be higher in non-Hispanic white males than Mexican American and non-Hispanic black men. But in contrast, it is more common in Mexican American women than in non-Hispanic black or non-Hispanic white women.
What are the numbers behind metabolic-syndrome traits?
According to many organizations, such as the National Heart, Lung, and Blood Institute (NHLBI), the American Diabetes Association, the American Heart Association (AHA), and the Diabetes Prevention Support Center, any three of the following five traits in the same person meet the criteria for metabolic syndrome. Many of these traits are related to the foods we eat (note: the term “mg/dl,” also seen as “mg/dL,” means milligrams per deciliter, a unit of measure):
Abdominal obesity , One metabolic syndrome trait is a high waist circumference, often called an “apple-shaped” body (as opposed to what is called a “pear-shaped” body). This means a waist circumference of 40 inches (102 centimeters) or more in men and 35 inches (88 centimeters) or more in women (there are also different criteria for various ethnic groups, too; for example, for Asian Americans, the values are greater than or equal to 35 inches [90 centimeters] in men and greater than or equal to 32 inches [80 centimeters] in women). (For more about abdominal obesity, see this chapter.)
Serum triglycerides (or triglycerides) , This reading is included in the test for metabolic syndrome if a person has a triglyceride reading of 150 mg/dl or above and is taking medicine for high triglycerides. (For more about triglycerides, see the chapter “How Diabetes Affects the Circulatory System.”)
Cholesterol , The cholesterol in the body has “good” and “bad” types.
The “bad” cholesterol is LDL (low-density lipoprotein), but that reading is not used in determining metabolic syndrome.
The “good” cholesterol, HDL (high-density lipoprotein), is used: If the HDL cholesterol reads 40 mg/dl or lower in men and 50 mg/dl or lower in women, then it is part of the list for metabolic syndrome.
In addition, taking medicine for low HDL cholesterol is included in the metabolic-syndrome list. (For more about cholesterol, good and bad, see the chapter “How Diabetes Affects the Circulatory System.”)
Blood pressure , For blood pressure to be added to the list of metabolic-syndrome traits, there must be a reading of 130/85 or more (systolic over diastolic numbers), although this reading is often debated, usually in favor of a bit higher reading. Another trait of metabolic syndrome is taking medicine for high blood pressure. (For more about blood pressure, see the chapter “How Diabetes Affects the Circulatory System.”)
Blood glucose , Another metabolic-syndrome trait is high blood glucose levels. Levels of fasting blood glucose would measure 100 mg/dl or above (although this number is also debated, with several researchers suggesting it should be even lower). Taking medicine for high blood glucose is also included in metabolic syndrome.
A common sense treatment for obesity and related diseases such as metabolic syndrome is weight loss through exercise.
How is metabolic syndrome treated?
According to almost every health-related organization, such as the American Heart Association and the American Diabetes Association, there are several things a person with metabolic syndrome can do to help lower the risk of developing cardiovascular disease and/or diabetes. The major ways are for a person to lose weight, eat a healthy diet, and increase physical activity.
RISKS OF TYPE 2 DIABETES
For adults between 18 and 45, what are some risk factors for developing type 2 diabetes?
People between the ages 18 and 45, and with a body mass index of 25 or higher (for more about body mass index, or BMI, see the chapter “Diabetes and Obesity”) should be tested if they have one of the following risk factors for developing type 2 diabetes:
• The person has a mother, father, brother, or sister with diabetes.
• The person is physically inactive.
• The person is of African American, Asian American, Hispanic American, Native American, or Pacific Islander decent.
• The person has given birth to a baby weighing more than 9 pounds (4 kilograms) or has had gestational diabetes during pregnancy (for more about gestational diabetes, see the chapter, “Other Types of Diabetes”).
• The person has a blood pressure of around 140/90 mm Hg or higher or is being treated with blood pressure-lowering medications (for more about high blood pressure, see the chapter “How Diabetes Affects the Circulatory System”).
• The person has abnormal blood lipid (fat) levels, such as HDL cholesterol levels below 35 mg/dl or triglyceride levels over 250 mg/dl. (For more about cholesterol and triglycerides, see the chapter “How Diabetes Affects the Circulatory System.”)
• The person has measured levels that indicate impaired glucose tolerance or impaired fasting glucose after being tested for diabetes.
• A female has polycystic ovary syndrome or (males and females) a history of vascular problems.
• The person has an HbA1c level that is greater than 5.7 percent. (A reading of 5.7 percent means a person is not yet considered to have diabetes but has a higher chance of developing diabetes; health care professionals consider a person to be diabetic if the HbA1c number is greater than 6.5 percent.)
If one or more of these items fits a person, and he or she is found not to have diabetes, then the test should be repeated in three years or as the health care professional suggests, or repeated, of course, if the person starts to develop symptoms.
For a person older than 45, what are risk factors for developing type 2 diabetes?
There are several risk factors for type 2 diabetes for adults age 45 years or older. They include:
A family history of diabetes, especially in the immediate family.
• Being overweight, and especially if a person is obese (generally a body mass index, or BMI, over 30; for more about BMI, see the chapter “Diabetes and Obesity”).
• A lack of regular exercise (often connected with a sedentary lifestyle in older people).
• Being from an ethnic or racial group that is more inclined to type 2 diabetes, including African Americans, American Indians, Hispanic Americans, Asian Americans, and Pacific Islanders.
Do people with type 2 diabetes ever need insulin injections instead of oral medication?
When people with type 2 diabetes have the disease for a long time, their use of oral medications may not work as well. Thus, one of the only ways to keep the blood glucose levels in balance is to begin using insulin. In combination with eating well, physical activity, and often other medications (including oral diabetes medicines), insulin becomes an additional help in controlling blood glucose levels. (For more about diabetes medications, see the chapter “Taking Charge of Diabetes.”)
What are some long-term complications of diabetes, especially type 2?
There are possible complications if a person has diabetes in the long term, in other words, the longer a person has diabetes, the more the possible risk of complications increases. These complications include heart attack, stroke, blindness, kidney failure, and amputations. But many of these risks can be mitigated or at least lessened by rigorous blood-sugar control and also by treating a diabetic for high blood pressure and/or high cholesterol if necessary.
The Handy Diabetes Answer Book
OTHER TYPES OF DIABETES
GESTATIONAL AND PREGESTATIONAL DIABETES
What are some connections between diabetes and pregnancy?
One connection between diabetes and pregnancy is pregestational diabetes. This is when a woman already has insulin-dependent diabetes and becomes pregnant (see below). The most well-known connection between diabetes and pregnancy is a condition called gestational diabetes. In the United States, it occurs in about 4 to 9 percent of pregnant women (the percentage varies depending on the study). Worldwide, it has been reported by some studies to occur in about 19 percent of pregnant women.
What is gestational diabetes?
Gestational diabetes occurs when a pregnant woman develops high blood glucose levels, even if she did not have diabetes before pregnancy. This type of diabetes generally develops during the woman’s second trimester and usually disappears after the baby is born. According to the American Diabetes Association, this condition is also thought to raise the mother’s and child’s risk for developing type 2 diabetes later in life.
Why do some pregnant women develop gestational diabetes?
Although not all studies agree, most research seems to indicate gestational diabetes may be caused by the hormones in the fetus’s placenta. This connection between the mother and fetus, which supplies the nutrients the baby needs, may block the action of the mother’s insulin throughout the body. If left untreated, gestational diabetes can result in very large babies and possibly the need for a caesarean delivery.
What is the O’Sullivan test?
The O’Sullivan test is a one-hour glucose-tolerance test (GTT) that is given to pregnant women to screen for gestational diabetes. It is most often performed between the 24th and 28th weeks of pregnancy.
What is pregestational diabetes?
Pregestational diabetes is used to describe the condition of a woman who already has insulin-dependent diabetes and becomes pregnant. Like gestational diabetes, pregestational diabetes can have consequences for the woman’s infant, especially if the mother’s blood glucose levels are not controlled during pregnancy.