Australian researchers have found that even before the disease becomes full blown diabetes increases a persons risk for heart disease.
With type 2 diabetes the body is unable to produce or properly use insulin properly; in pre-diabetes, the body has started having problems handling blood sugar, but those problems have not yet become diabetes.
It is common that people before they develop type 2 diabetes, experience problems metabolizing sugar, a symptom picked up by a blood glucose test.
Having abnormal blood glucose levels after fasting is a condition known as pre-diabetes and it affects 56 million people in the United States.
Researchers at the International Diabetes Institute in Melbourne, Australia conducted a large study involving 10,429 Australians with an average age of 51-63 years, over an almost five year period and they found that people with pre-diabetes had more than double the risk of death from heart disease.
Type 2 diabetes is becoming an increasing problem throughout the world and it is inked with obesity, poor diet and lack of exercise; it can lead to blindness, loss of limbs, heart disease and premature death.
Elizabeth Barr and her colleagues found in their study that those patients considered pre-diabetic had a 2.5 times higher risk of death from heart problems than those who metabolized glucose normally.
The research team say the study confirms the clinical importance of pre-diabetes, and suggests there is a need to target glucose abnormalities with lifestyle interventions.
The Australian team recommend boosting heart health in anyone with blood sugar problems, even if those problems are too mild to qualify as diabetes.
Other research has shown that people with pre-diabetes can prevent type-2 diabetes through dietary changes and increased physical activity.
The pre-diabetes finding also supports other research which too suggests that people with type 2 diabetes have a far higher risk of stroke even within the first five years of diagnosis.
That large Canadian study by researchers at the University of Alberta, evaluated 12,272 people with type 2 diabetes who had all recently been diagnosed with diabetes and had a mean age of 64 years.
When the researchers compared the rate of stroke among the diabetics in the study with the general population after five years they found the type-2 diabetics had double the risk of having a stroke.
The study is one of the first to look at the stroke risk of newly diagnosed diabetics; most studies tend to look at stroke rates among diabetics within 10 years of diagnosis.
According to experts nearly 21 million people in the U.S. have diabetes, and most of those have type 2 diabetes; another 54 million people have pre-diabetes and many more are unaware they have either.
Symptoms of type 2 diabetes may include fatigue, frequent urination, increased thirst or hunger, weight loss, blurred vision, and the slow healing of wounds or sores.
Although some people with pre-diabetes may have these symptoms, most people don't. Diabetes becomes more common with age.
The Australian study is published in the journal Circulation; the Canadian study appears in the American Heart Association's journal Stroke.