Study Looks at Why Diabetes Makes Heart Disease WorseThursday, August 16, 2012
Researchers at Washington University School of Medicine in St. Louis have received a $4.7 million grant from the National Heart, Lung, and Blood Institute to investigate heart disease in patients with diabetes.
“Diabetes is an incredibly common problem,” says Jean E. Schaffer, MD, the Virginia Minnich Distinguished Professor of Medicine. “It affects a huge swath of the population. Importantly, people with diabetes don’t just have a metabolic disorder. They develop complications in many organs. And one of the most deadly complications is heart disease. We’re particularly interested in why people with diabetes suffer from unusually severe forms of heart disease.”
For reasons not fully understood, people with diabetes are more likely to develop blockages in arteries. After a heart attack, the course of the subsequent heart disease is more aggressive than in people without diabetes.
And even independent of blocked arteries, there is evidence that their hearts do not function like those of individuals without diabetes.
According to the Centers for Disease Control and Prevention, almost 26 million Americans are living with type 2 diabetes and another 79 million with undiagnosed diabetes or pre-diabetes, a condition that increases their risk of developing the full-blown variety. With such statistics, it is becoming increasingly important to explore the reasons behind the aggressive progress of cardiovascular disease in patients whose bodies do not properly regulate blood sugar.
Schaffer and her colleagues suspect a likely culprit is abnormal lipid metabolism. Lipids are a class of molecules that include fats, such as fatty acids and triglycerides. Past studies have shown that patients with diabetes store higher levels of these lipids in their heart muscle, likely impairing cardiac function. These lipids appear to lead to inflammation and can also damage important parts of heart cells, such as proteins and DNA, leading to heart muscle dysfunction.
“The problem is that we haven’t been able to make strong links between what we measure in a fasting blood sample, like triglycerides and free fatty acids, and the degree of heart muscle dysfunction,” Schaffer says. “In this type of heart muscle disorder, these common blood tests are not a good predictor of who is at highest risk for heart disease.”
The goal of the new research program is to identify better measures of heart disease in patients with diabetes.