At least 10 percent of people who have a heart attack may have undiagnosed diabetes, according to new research presented at the American Heart Association’s Quality of Care and Outcomes Research Scientific Sessions 2014.

To understand more about undiagnosed diabetes, researchers studied data on 2,854 heart attack patients without diagnosed diabetes at 24 U.S. hospitals. Using blood samples collected from these patients, researchers used an A1C test to determine blood sugar levels. The results were not provided to physicians treating the heart attacks, although some of the physicians ordered the test on their own.

Researchers found:

  • Of all heart attack patients, 287 patients — about 10 percent — had diabetes, based on the A1C test done by researchers.
  • Less than a third of the 287 received diabetes education or medication when they were discharged from the hospital.
  • Doctors treating the heart attacks did not recognize diabetes in 69 percent of the 287 patients.
  • Doctors treating the heart attacks were 17 times more likely to recognize diabetes if they ordered and checked the results of an A1C test, and they were even more likely to recognize diabetes when A1C levels were higher.
  •  Six months after discharge, 71 percent of patients diagnosed by their doctor when hospitalized were on some medication for diabetes compared to less than 7 percent of patients whose diabetes was not diagnosed at that time.

Diabetes, which causes blood sugar to reach dangerous levels, significantly raises the risk for heart attack. Two out of three people with diabetes die from cardiovascular disease, according to the AHA.

“Diagnosing diabetes in patients who have had a heart attack is important because of the role diabetes plays in heart disease,” said Suzanne V. Arnold, M.D., M.H.A., the study’s lead author and assistant professor at Saint Luke’s Mid America Heart Institute and the University of Missouri at Kansas City. “By recognizing and treating diabetes early, we may be able to prevent additional cardiovascular complications through diet, weight loss and lifestyle changes in addition to taking medications. Another important reason to diagnose diabetes at the time of heart attack is that it can guide the treatments for the patient’s coronary artery disease.”

People who have a heart attack should ask for a diabetes test if they have a family history of the disease or other risk factors such as overweight or obesity, physical inactivity and high blood pressure. Those already diagnosed with diabetes also should ask for more information on the disease and how to manage it.

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