The Risk of Heart Disease in 'Pre-diabetics'

Older adults with an impaired ability to tolerate and process glucose but are not considered diabetic are at an increased risk for heart disease, a new study has found.

Researchers at Yeshiva University’s Albert Einstein College of Medicine looked at nearly 60 older adults with an average age of 71. For the study, participants—half of whom had a normal glucose tolerance and the other half of whom had post-challenge hyperglycemia (PCH)—were given a standard, high carbohydrate meal.

The adults with PCH were found to have higher glucose and insulin levels after the meal, as well as elevated triglycerides. Compared to the control subjects, their blood vessels were more inflamed, and they had higher levels of a protein that promotes clotting. Additionally, tests to evaluate blood vessel function showed impairment in only the PCH group. All of these factors have been shown to raise an individual’s risk for heart disease.

"In most cases, this mild form of high blood glucose causes no symptoms and is often overlooked by both doctors and patients, but studies have shown that it may be associated with increased risk of heart disease," said Jill P. Crandall, MD, associate professor of clinical medicine and director of the Diabetes Clinical Trials Unit at Einstein. "The purpose of this study was to explore the cardiovascular risk profile of older adults with pre-diabetes."

Using the standard oral glucose tolerance test to evaluate the elderly could help to identify these high-risk individuals, the researchers noted.

More than an estimated 37 million Americans over the age of 65 have diabetes, which accounts for nearly one-quarter of that population. Additionally, between 20 and 30 percent of American seniors—between 7.5 and 11.1 million—have not been diagnosed as diabetic but have impaired glucose tolerance.

In spite of the results, published online in the Journal of Clinical Endocrinology and Metabolism, the researchers say that it is not known if treatment to reduce mild hyperglycemia will lower the risk in these patients of heart disease.

"Consequently, other interventions designed to reduce the risk of cardiovascular disease, including the use of statins and aspirin, should be strongly considered for older adults with PCH," said Crandall.