What is diabetes mellitus?

Diabetes mellitus (di”ah-BE’teez or di”ah-BE’tis meh-LI’tis) is the inability of the body to produce or respond properly to the  hormone insulin. The body needs insulin to convert glucose (“blood sugar”) into energy. Diabetes is defined as a fasting plasma glucose of 126 mg/dL or more measured on two occasions.


The two major forms are type 1 and type 2 diabetes. Type 2 diabetes, the most common form, usually appears in adults, often in middle age. Type 2 diabetes is often linked with obesity and may be delayed or controlled with diet and exercise. (Obesity and physical inactivity are two risk factors for type 2 diabetes.) In a mild form, it can go undetected for many years. Untreated diabetes can lead to many serious medical problems, including cardiovascular disease.

The other form is type 1 or juvenile diabetes. It typically begins early in life. People with type 1 diabetes have a primary insulin deficiency. They must take insulin to stay alive.

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. Part of the reason for this is that diabetes affects cholesterol and triglyceride levels. Often people with diabetes also have high blood pressure, increasing their risk 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 130/85 mm Hg.

How dangerous is diabetes?

It’s very dangerous. Just look at these facts:

  • Diabetes kills more than 60,000 Americans each year. Its complications contribute to another 190,000 deaths.
  • People with diabetes are two to four times more likely to have heart disease or a stroke. Their heart disease also tends to be more severe. They have a higher risk of congestive heart failure and other complications, too.
  • Diabetes causes nerve damage in the heart. This makes painless heart attacks more likely and harder to diagnose. Heart attacks are more likely to be fatal in people who have diabetes than in those who don’t.
  • Diabetes tends to lower “good” HDL cholesterol, and raise “bad” LDL cholesterol and triglyceride levels. This increases the risk of heart disease and stroke.
  • Eighty to ninety percent of people with diabetes are overweight or obese. Many people with diabetes also have high blood pressure and aren’t physically active. These factors raise their risk for heart disease and stroke even more.
  • Nearly 60 million Americans have insulin resistance and 25 percent of them will probably go on to develop diabetes.

Note: Unless otherwise stated, statistics given here are for the most recent year available and are from the National Center for Health Statistics and the American Heart Association, Heart and Stroke Statistical Update.

Besides being a risk factor for CVD, diabetes also can cause or lead to:

  • blindness.
  • kidney disease.
  • nerve disease.
  • limb amputations.

Diabetes also can be debilitating and reduce the quality of life. Many people with diabetes report depression and living a less-active life.

Are people with diabetes at high risk for cardiovascular diseases (CVD)?

Yes! People with diabetes are at high risk for such cardiovascular disorders as coronary heart disease (heart attacks), stroke and peripheral vascular disease. In fact, two out of three people with diabetes die from CVD. A survey released by the American Heart Association showed that only a third of diabetes patients considered cardiovascular disease to be the most serious complication, yet nearly two thirds of them already have experienced some form of cardiovascular disease. At the same time, almost all these patients admitted there were things they could do to prevent heart problems.

The good news is that people with diabetes can reduce their risk for cardiovascular disease.

  • Talk to your doctor
  • Eat right and exercise
  • You may have to lose weight
  • And learn about insulin resistance
What are major risk factors for CVD?

There are six. They are:

Other Sources of Information

American Diabetes Association