Diabetes and heart disease: A fatal link
Editor's note: Ann Curley is the assignment manager for the CNN Medical News unit and a type I diabetic. Diabetes is the fifth-leading killer of Americans, according to the American Diabetes Association. A sobering two out of three people with type I or type II diabetes will die from a heart attack or stroke -- the combined leading causes of death among diabetics. There are few diabetics who haven't heard horror stories about patients who have lost limbs or gone blind because of poor disease control. Keeping a trio of factors -- blood glucose, blood pressure and cholesterol levels -- within recommended ranges is key to reducing the risk for diabetes-related complications such as heart attacks, strokes and peripheral vascular disease, which occurs when blood flow to the limbs is impaired. Health professionals often tell diabetics to mind their "ABCs." or glycates -- the hemoglobin. The more excess glucose, the more sugar that sticks to the hemoglobin. And these clumps of glucose and hemoglobin can be measured as a percentage of the blood -- the A1C reading. The test is a bit of a lie detector for glucose control -- your A1C will tell your doctor how much extra sugar has been flowing around in your blood. A nondiabetic will have a normal A1C of 4 to 6 percent, which works out to an average blood sugar of about 65-135 milligrams per deciliter (mg/dL) of blood. The higher the number, the more glucose that is in the blood. A well-controlled diabetic should aim for an A1C of less than 7 percent, which is an average blood sugar of about 170 mg/dL. startclickprintexclude--> Cholesterol is transported in the body by carriers called lipoproteins. Low density lipoproteins, or LDL, carry most of the cholesterol. An excess of LDL in the blood can cause fatty material to deposit inside blood vessels, clogging and hardening them. This can lead to heart disease, stroke and other circulatory problems -- and is why LDL is often called the "bad" type of cholesterol. High density lipoproteins, or HDL, also transport cholesterol but seem to work to reduce the deposits of LDL cholesterol. HDL is often called "good" cholesterol because of how it works against LDL cholesterol. Triglycerides are a byproduct derived from calories not immediately used as energy, and they are stored in fat cells. Hormones release triglycerides from fat tissue. High triglycerides signal uncontrolled blood glucose levels in diabetics, and they can signal coronary artery disease in some people. startclickprintexclude--> The result: High glucose levels circulate in the bloodstream, unable to get through the cell doors and provide energy to the hungry cells. This is where problems begin. High blood glucose levels circulating through the body without being turned into cellular energy will begin to damage the body. "When the unfed cells are starved for their metabolic fuel, glucose, they become damaged and eventually die," explained cardiovascular surgeon Dr. Alon S. Aharon of University Hospitals of Cleveland/Case Western. "When the cells die, this may cause damage to the heart, brain and kidneys, among other organs." High glucose levels also affect blood fat levels. High glucose can prevent the HDL, or "good" cholesterol from binding to and processing other cholesterol and fats properly, leading to increased fat deposits in blood and blood vessels. This increases the risk for stroke, heart attack and peripheral vascular disease. "A large proportion -- a third to a half -- of the patients with heart disease and peripheral vascular disease have poorly controlled diabetes, which greatly impacts not only their long-term survival but their quality of life because of potential limb loss, kidney damage, and debilitating heart disease," Aharon said. The good news is that heart disease doesn't have to be a complication of diabetes. Controlling glucose levels, blood pressure and cholesterol will decrease the risk factors for heart disease and stroke. And those actions, combined with exercise, a healthy diet and not smoking, are a recipe for good body and heart health. |
