Size vs. shape: What’s more important for heart health?

When it comes to heart health, body shape matters: A new study finds that having an apple-shaped body may increase the risk for heart disease in people with diabetes.

In the study, people who had a higher waist circumference were more likely to have problems with the left ventricle of their heart, which is a common cause of heart disease, compared with people with smaller waists, according to the findings presented today (April 2) at the American College of Cardiology's annual meeting in Chicago.

"This study confirms that having an apple-shaped body — or a high waist circumference — can lead to heart disease, and that reducing your waist size can reduce your risks," Dr. Joseph Muhlestein, the director of cardiovascular research at Intermountain Medical Center in Utah and the senior author on the study, said in a statement. [Heart Disease: Types, Prevention & Treatment]

For this study, researchers used echocardiograms to look at how well the left ventricle of the heart was functioning in 200 men and women who had either type 1 or type 2 diabetes. The participants in the study didn't have any symptoms of heart disease, but they were considered "high risk" for developing the disease based on other factors.

The left ventricle of the heart is responsible for pumping blood out of the heart to the brain and the rest of the body. When this ventricle is not working properly, some blood can back up into the lungs and lower extremities, which can lead to heart failure and sudden cardiac arrest.

The researchers "specifically found that waist circumference appears to be a stronger predictor for left-ventricle dysfunction than total body weight or body mass index," Dr. Boaz Rosen, a cardiologist at Johns Hopkins Hospital in Baltimore and the lead author on the study, said in a statement. This means that, for example, a person with a larger waist and lower body mass index (BMI) may be more likely to develop heart disease than is a person with a narrower waist but higher BMI. [8 Reasons Our Waistlines Are Expanding]

The researchers noted that additional studies are needed to confirm the results. The study did not look at the actual rates at which the participants developed heart problems.

"It will be important to see if these patients are indeed at risk of developing [heart problems] in the future," Rosen said.

But this is not the first study to suggest that carrying more weight around the abdomen may be harmful for your heart. For example, a 2011 study of nearly 28,000 men and more than 41,000 women found that a higher waist circumference was significantly associated with heart-disease risk.

The results of the current study have not been published in a peer-reviewed journal.