Prevalence of Diabetes in Women
As a woman with diabetes, you have plenty of company. The American Diabetes Association estimates that about 9.3 million women—8.7% of all women over age 20—have diabetes. This breaks down to:
- 4.7% of white females *
- 12.6% of black females *
- 11.3% of Mexican-American females *
As these figures illustrate, minority women are more likely to have diabetes than are their white counterparts, according to the Centers for Disease Control and Prevention. Interestingly, women in general are more likely to have diabetes than are men.
If you have diabetes, you probably know about the potential for eye and foot problems. But how much do you know about the most common complication of diabetes – cardiovascular disease?
The fact is, women with diabetes are up to five times more likely to develop cardiovascular disease than are women who do not have diabetes.
And the consequences are serious – deaths from heart and blood vessel disease in women with diabetes have increased by 23 percent over the past 30 years, while the death rate from cardiovascular disease has dropped by 27 percent in women without diabetes.
Overall, women with diabetes have a two to four times higher risk of a stroke or death from cardiovascular disease compared with women who do not have diabetes.
Unfortunately, about one-third of women with diabetes do not know they have the disease. For all these reasons, Cleveland Clinic experts in diabetes and heart disease recommend that every woman have her blood glucose tested, particularly those women with a family history of diabetes.
When you know you have diabetes based on the results of a blood test, you can take steps to manage your condition and live a longer, healthier life.
What is diabetes?
Diabetes is a disease of the pancreas. Situated behind the stomach, the pancreas is the organ responsible for producing the hormone insulin. After food is eaten, it is broken down into glucose, the simple sugar that is the main source of energy for the body's cells. Insulin helps glucose enter the cells where it is converted to energy.
In diabetes, the pancreas either cannot produce enough insulin, cannot use insulin correctly or both. When insulin does not function properly, glucose cannot enter the cells. As a result, glucose levels in the blood increase and the cells lack the energy they need to function.
There are two forms of diabetes:
- Type 1: also known as insulin-dependent or juvenile diabetes.
- Type 2: also known as adult-onset diabetes.
Type 2 diabetes is the more common form of the disease in the United States.
Reducing heart disease risk
Two of the primary risk factors for heart disease are high LDL cholesterol levels and elevated levels of triglycerides (a form of fat derived from fats and oils), and people with diabetes are more likely to have both of these. This link naturally has led to the question of whether tighter control of blood glucose levels will reduce the risk of heart disease in people with diabetes. The data we currently have on diabetes control and heart disease are sparse. Fortunately, a major clinical trial is now in progress that should provide more definitive answers.
Statins: first-line therapy
Meanwhile, we do have strong data that demonstrate a reduction in the risk of heart disease in women (and men) who have diabetes when LDL cholesterol levels are reduced with medication.
Statins, a class of drugs that lower LDL cholesterol, are proven to reduce the risk of heart disease by as much as 30 percent in patients who do not have diabetes. In clinical trials of these drugs in people with diabetes, reducing LDL levels also leads to significant reductions in the incidence of heart disease and overall mortality.
The Collaborative Atorvastatin Diabetes Study (CARDS), published in January 2005, was the first large study to focus specifically on the role of a statin in patients age 40 to 75 with type 2 diabetes without cardiovascular disease and with average or below average cholesterol levels. More than 2,300 patients (men and women) were randomly assigned to take either 10 mg. of atorvastatin or an inactive placebo each day.
After four years, the preliminary data showed that atorvastatin reduced LDL cholesterol (the bad kind that causes heart disease) by an average of 40 percent and reduced the risk of acute coronary heart disease death, fatal or non-fatal heart attack, stroke and other cardiovascular events by 37 percent. The overall risk of death was reduced by 27 percent. In fact, the results were so dramatic that the trial was halted a year early.
The very strong link CARDS and other trials have established between LDL levels and heart disease suggests that LDL cholesterol plays an even more important role in determining heart disease risk in people with diabetes than in people who don’t have diabetes. For diabetes patients, borderline-high LDL cholesterol (between 130 and 160 mg/dl) levels carry the same risk for heart disease that an extremely high LDL cholesterol level (over 160 mg/dl) does in someone without diabetes.
Facts on fibrates
Fibrates are a class of drugs that are commonly used to reduce triglycerides and raise HDL cholesterol (the protective kind) and have been proven to reduce the risk of cardiovascular events in certain groups of patients. Although statins still remain as first-line therapy for people with diabetes, the question has been raised as to whether fibrates could be equally – or more – effective than statins. Could the fact that these drugs also improve the triglyceride profile mean that they have an added benefit?
Not so, reports a group of Australian, Finnish and New Zealand investigators. They designed the first large-scale study to evaluate the efficacy of fibrate therapy on reducing cardiovascular events specifically in people with diabetes. Their study, the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD trial), was published in November 2005 in the prestigious medical journal Lancet.
The 10,000 people in the study, ranging in age from 50 to 75, all had diabetes and low HDL cholesterol levels (the good kind that protects against heart disease), near normal LDL cholesterol levels and elevated triglycerides. Of the total group, about 80 percent did not have cardiovascular disease at the outset and 20 percent did. Half the subjects in the study received 200 mg of fenofibrate daily, and half received placebo (an inactive “fake” pill).
After five years, the researchers found that fibrate therapy reduced the risk of coronary events by 11 percent – mainly due to a 24 percent reduction in non-fatal heart attack and a 21 percent reduction in revascularization procedures (including bypass surgery and interventional procedures such as balloon angioplasty and stenting). But overall, fibrate therapy did not reduce the risk of death in these patients.
Fibrates’ prevention effect was small in people who did not have cardiovascular disease at the start of the study; in people with existing cardiovascular disease, fibrate therapy had virtually no effect on preventing another cardiac event. The conclusion: statins are still better than fibrates for reducing cardiovascular death in patients with diabetes, and the current treatment guidelines that recommend statins in people with diabetes still hold.
Other Heart Disease Risk Factors
High blood pressure
Diabetes is associated with an increased risk of developing high blood pressure, another risk factor for heart disease, kidney disease and eye problems. High blood pressure can be managed effectively through a combination of diet, exercise and medication. But be aware that some blood pressure medications may affect your blood glucose (sugar) levels. Your doctor can help you find the best strategy for controlling your blood pressure, including the right medication for you.
The combination of high blood pressure and high blood glucose levels that occurs in people with diabetes creates a significant risk for kidney (renal) disease. Over time, diabetic kidneys lose their ability to filter waste products from the blood and can eventually fail completely. In addition to the problems caused by kidney failure, kidney disease is linked to a higher risk for heart disease that is independent of other risk factors.
Take preventive action
As a woman with diabetes, the most important action you can take to reduce your risk of diabetes-related complications is to manage your disease to the best of your ability. You probably already know the tools to accomplish this: proper nutrition, regular exercise and medication. Your doctor and dietitian are the professionals who are best equipped to help you put these tools to work for you.
Make an Appointment with a Specialist
- To make an appointment with a Cleveland Clinic expert in diabetes, call the Department of Endocrinology at 216.444.6568 or toll-free 800.223.2273, ext. 4-6568.
- To make an appointment with a specialist in the Women’s Cardiovascular Center, please call 216.444.9353 or toll-free 800.223.2273 ext. 4-9353.
If you have any questions or need more information, call the Miller Family Heart & Vascular Institute Resource Center at 216.445.9288 or toll-free at 866.289.6911, contact us, or chat online.
Resources and References
From the Cleveland Clinic
Other Resources and References