When children have high cholesterol or blood pressure, their parents may have increased risks of diabetes and heart disease down the road, a new study finds.

The study, of 519 Ohio families, found that a 12-year-old's weight, cholesterol and blood pressure helped predict the odds of a parent developing heart disease, high blood pressure or diabetes over the next three decades.

Researchers say the findings suggest that screening kids could have the "bonus" of spotting at-risk parents.

"Pediatric risk factors -- cholesterol, triglycerides, high blood pressure -- identified families where parents were at increased risk," said Dr. Charles J. Glueck of Jewish Hospital of Cincinnati, one of the researchers on the study.

One reason that's important, he told Reuters Health, is that many parents may not get check-ups themselves, but will regularly take their kids to the doctor.

However, not everyone agrees that children should have numerous screening tests.

It's standard for children to have their weight and blood pressure measured at "well-child" visits to the pediatrician. But only recently did experts start recommending cholesterol checks.

In November, the U.S. National Institutes of Health issued new guidelines saying children should have their cholesterol measured between the ages of 9 and 11, and again between the ages of 17 and 21. The American Academy of Pediatrics also endorsed the recommendation.

That was a shift from what experts had traditionally recommended -- namely, screening cholesterol only in certain at-risk kids, like those with diabetes or a family history of early heart disease.

And some critics questioned the new guidelines, pointing out that there's no hard data showing that screening kids' cholesterol helps their heart health in the long run.

In 2007, the U.S. Preventive Services Task Force (USPSTF) -- an expert panel with federal support -- said there was "insufficient" evidence to recommend for or against routine cholesterol tests for children and teenagers.

"There is still a lot of debate going on," Glueck said.

But he thinks the current study, plus another recent analysis of the same group, give some needed information. "Our findings provide some hard data: If you know children's risk factors, what does that tell you? It tells you a lot," Glueck said.

Heart disease, stroke, diabetes

The study, reported in the Journal of Pediatrics, included 852 school students who, at an average age of 12, had their cholesterol, blood pressure, triglycerides and weight measured. They were reassessed 26 years later -- as were their parents, who were 66 years old, on average.

In nearly half of the families -- 47 percent -- a parent had suffered a heart attack, stroke or needed a procedure to clear blocked heart arteries by the end of the study period. In 37 percent, a parent had developed diabetes.

Overall, Glueck's team found, parents were about twice as likely to suffer early heart disease or stroke (age 60 or younger) when their child had had high blood pressure at age 12.

Parents' odds of cardiovascular problems at any age were also higher when their child had had high levels of "bad" LDL cholesterol or triglycerides.

And when children were overweight, their parents' odds of developing diabetes or high blood pressure doubled.

In an earlier study, Glueck's team had found that childhood test results also predicted the kids' own risks of developing heart problems, diabetes and high blood pressure by their late-30s.

All of that suggests that childhood screenings can help predict future risks -- in kids and parents. But there is no hard evidence that screening children actually cuts their odds of diabetes or cardiovascular disease in the long run.

Study unlikely

To pin that down, Glueck noted, researchers would have to follow a large group of screened children for decades into adulthood, and compare them to a group who'd been randomly assigned to forgo screening as kids.

"It's very unlikely a study like that would ever be done," Glueck said.

There's also a question of expense, since the cost of screening all children for high cholesterol adds up, for an uncertain benefit. And if a child were to be put on a cholesterol-lowering statin, no one is sure what the potential side effects of early and long-term use might be.

That's one reason the USPSTF did not come down on the side of universal screening.

According to Glueck, most children with high cholesterol could be treated with a healthier diet. It's estimated that about 15 to 20 children out of every 300 U.S. kids may have high cholesterol that's related to diet and lifestyle.

A smaller proportion -- about one in every 300 to 500 children -- have an inherited form of high cholesterol called familial hypercholesterolemia. That causes high LDL levels starting early in life, and often leads to heart disease by the time a person is in his 40s or 50s.

Those kids may be placed on statins.