A new study suggests that 13-year-olds with insulin resistance may face a higher risk of heart disease and diabetes by their 19th birthday.
Insulin resistance occurs when the body has a weakened response to insulin, a hormone necessary to maintain normal blood sugar levels.
The researchers say the increased risk of heart disease and type 2 diabetes found in teens with insulin resistance was independent of other known risk factors for these diseases, such as obesity.
"This is the first study to show insulin resistance by itself is a significant predictor of cardiovascular disease, beginning in childhood," says researcher Alan Sinaiko, M.D., in a news release. Sinaiko is a professor of pediatrics at the University of Minnesota Medical School in Minneapolis.
Insulin Resistance Tied to Heart Risk
In the study, published in Hypertension: Journal of the American Heart Association, researchers followed 357 fifth through eighth grade school students in Minneapolis.
At age 13, each underwent a complete physical examination and was screened for insulin resistance. The screening for insulin resistance was repeated at ages 15 and 19.
The results showed that teens with signs of insulin resistance at age 13 were more likely to have risk factors for heart disease at 19.
The children who were insulin resistant at 13 were likely to have elevated systolic blood pressure (the top number in a blood pressure reading) and a higher blood fat level (triglycerides). Higher levels of blood triglycerides are associated with heart disease and a higher risk of type 2 diabetes.
In addition, the higher insulin resistance scores were associated with higher blood pressure readings and blood triglyceride levels.
When insulin resistance, high systolic blood pressure, low "good" HDL cholesterol, high blood triglycerides, and obesity occur at the same time, it creates a condition known as metabolic syndrome.
That condition has been shown to significantly increase the risk of heart disease and type 2 diabetes.
SOURCES: Sinaiko, A. Hypertension: Journal of the American Heart Association, Aug. 22 rapid access edition; vol. 48: pp 1-7. News release, American Heart Association.
By Jennifer Warner
Reviewed by Brunilda Nazario, M.D.
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