In all, 72 percent of female diabetics have at least one major cardiovascular problem, including stroke, heart attack and high blood pressure, the Centers for Disease Control and Prevention says. The proportion is even greater for women 75 or older. Moreover, the survey finds that almost three in 10 women released from the hospital after treatment for heart problems are diabetics.
The new figures appear in the Nov. 2 issue of the CDC's Morbidity and Mortality Weekly Report.Cardiovascular disease is the leading killer of women in this country, claiming more than 500,000 in 1998 alone, according to the American Heart Association. And while doctors have long known that people with diabetes face sharply higher risks of dying, the new data gives them a more complete view of the impact diabetes has on the heart, says Dr. Michael Engelgau, a CDC medical epidemiologist who helped prepare the report.
"The diabetes piece is part of a bigger picture that all seems to come together in ways that we don't understand exactly, but we certainly understand the outcome pretty well," he says.
Officials say diabetics can decrease their risk of potentially fatal heart disease by controlling blood sugar, blood pressure and cholesterol levels.
"With 16 million people and counting, diabetes is growing at an alarming rate in America," Secretary of Health and Human Services Tommy Thompson says in a statement. "Diabetes has increased 49 percent from 1990 to 2000, and projections indicate a 165 percent increase by the year 2050. If you have diabetes, you are at a very high risk for heart attack and stroke. But you can take control and lower your risk with this new treatment approach."
There are two types of diabetes: Type I, which typically sets in during childhood and involves inadequate production of the hormone insulin; and Type II, the adult-onset form, which occurs when the body's cells no longer respond to the sugar-processing substance. Type I diabetes affects about 1 million people in this country, while an estimated 15 million Americans suffer from Type II diabetes -- a number that is growing as the nation becomes more obese.
The latest study was based on data collected between 1997 and 1999 and included almost 40 million women over the age of 18. Of those, 4 million had diabetes. Cardiovascular problems increased with age, affecting about 40 percent of women under age 45 but 85 percent of those 75 or older. Such ailments were more common in blacks than in whites or Hispanics, the researchers say.
High blood pressure was the leading cardiovascular complication among diabetics, affecting 64 percent of women. Other heart illness, coronary heart disease, heart attack, chest pain, or angina, and stroke made up the rest of the list.
Not surprisingly, diabetes was also common among women hospitalized for heart trouble. In 1997, for example, 28 percent of women discharged after treatment for cardiovascular illness also had the blood sugar disorder. Again, age was a strong predictor of which patients would have both conditions.
In a related survey, the CDC also found that diabetes accounts for between 44 and 85 percent of all preventable leg, foot and toe amputations in this country. People with the sugar syndrome are 28 times more likely than non-diabetics to undergo non-trauma amputations of their extremities. Men, blacks and the elderly bear the biggest burden of this risk.
The studies are far from the first to show that diabetes can cause serious, even fatal, problems if unchecked.
Women with Type II diabetes are more likely to lose mental ability as they get older than those without the blood sugar problem, recent research suggests. Those who've had the disease longer face still greater odds of serious mental decline.
And men are not immune to its destruction. Male diabetics are two to three times more likely than non-diabetics to die from heart and vessel disease, and four times more likely to suffer fatal strokes. And scientists have found that even slight elevations in blood sugar -- reflecting insulin resistance -- boost mortality rates from cardiovascular disease and other causes.
Although the latest study didn't look at death rates, Engelgau says mortality from cardiovascular diseases linked to diabetes has been steady in recent decades despite an overall decline in heart deaths. "The problem is not behaving as it is in the general population," he says.
Dr. Michael Criqui, a preventive cardiologist at the University of California at San Diego, says older drugs to control blood sugar helped ease non-cardiac complications of diabetes, such as blindness and kidney failure, which are caused by small vessel damage in those organs. But the drugs didn't seem to lower the risk of death from larger diseased vessels.
However, Criqui adds, a trickle of recent evidence shows that a new family of diabetes drugs called glitazones may help prevent cardiovascular deaths in diabetics. "I think there's hope, if not definitive proof," Criqui says.
What To Do
If you've got diabetes, keep your ABCs in check. That's short for: A1C, a measure of blood sugar concentration, which should be under 7 percent; blood pressure, which should be below 130/80; and cholesterol (the low-density, or LDL, form), which shouldn't top 100.
"People with diabetes know how important it is to control their blood glucose, but too little attention is paid to the role of cholesterol and blood pressure," Dr. Allen Spiegel, director of the National Institute of Diabetes and Digestive and Kidney Diseases, says in a statement. "Research shows that this new approach, aggressively treating these three risk factors, can save lives."