MONDAY, Oct. 11, 2004 (HealthDayNews) -- Teens who have insulin resistance could be more likely to suffer from high blood pressure when they reach adulthood, new research suggests.
Since high blood pressure is a known risk for cardiovascular disease, the finding could help spot children who face a higher risk for heart problems later in life, report University of Minnesota researchers.
"We found that insulin resistance as a predictor for cardiovascular risk begins at age 13," said study author Dr. Alan Sinaiko, a pediatrics professor at the University of Minnesota. He presented his findings on Oct. 10 at the American Heart Association's annual high blood pressure research conference in Chicago.
"Many of the efforts for predicting cardiovascular risk in childhood have been directed at obesity, but these results show that in addition to obesity, perhaps we should start looking at insulin resistance in developing preventive programs," he said.
Sinaiko added, however, that there is no simple test to assess insulin resistance, so clinical application of his research won't come for a number of years.
"Most teens are not screened for heart disease risk factors, and this study tells us that pediatricians and general-care practitioners need to begin to find people who will be having heart attacks when they are in their 40s," said Dr. Laurence Sperling, medical director of preventive cardiology at Emory University School of Medicine in Atlanta. "When they are younger, we can do a lot about it."
Insulin is a hormone produced by the pancreas to help the body use or store the blood glucose it gets from food. Insulin resistance, Sinaiko said, occurs when cells cannot absorb the proper amount of glucose, leaving high levels of sugar in the blood. When that happens, it may have adverse effects on processes that control blood pressure.
For the study, Sinaiko and his colleagues followed 357 children as they moved through their teenage years, testing them three times, at ages 13, 15 and 19, to assess how their bodies responded to insulin. The teens were all healthy children recruited through the Minneapolis school system.
At the age of 13, none of the children had high blood pressure -- the average blood pressure was 107/56. But 2 percent fulfilled adult criteria for other cardiovascular risks, such as being overweight, and having high levels of trigylcerides and low levels of HDL -- or "good" -- cholesterol.
By age 19, the children's blood pressure had increased, which is normal as children age, but researchers noted a further increase in blood pressure associated with an increase in insulin resistance. For every unit of insulin resistance at age 13, systolic blood pressure at age 19 had increased by 0.42 mm/Hg, Sinaiko said.
In addition, the researchers found that by age 19, there had been a 7 percent jump in the number of young people who met the adult criteria for cardiovascular risk, to 9 percent.
Sinaiko said he could not assess the prevalence of insulin resistance syndrome from his study, but other researchers have estimated that 4 percent of all children aged 11 to 19 and 30 percent of obese children in that age group have insulin resistance syndrome.
"This study clearly shows that cardiovascular risk starts early in life, and that we need to study these risks more intensively," Sinaiko said.
Dr. Robert Rapaport is director of the division of pediatrics, endocrinology and diabetes at Mount Sinai School of Medicine in New York City. He said, "This [research] is very interesting and quite important, confirming studies we have from another group of children born early in their gestational development who have insulin resistance and a tendency toward high blood pressure."
For more information about children and high blood pressure, visit the American Heart Association.