CHICAGO – Insulin pumps, used by tens of thousands of teenagers and others with Type 1 diabetes, can be risky and have been linked to injuries and even deaths, a study by federal regulators found.

Medtronic Diabetes

A 10-year study of patients 12 to 21 years old found 13 deaths related to pumps.

Parents should carefully watch their children's use of the pumps, researchers from the Food and Drug Administration wrote following the research.

They didn't advise against using the devices, but they called for more studies to address safety concerns in teens and even younger children who use the popular pumps.

The federal review of young people's use over a decade found 13 deaths and more than 1,500 injuries connected with the pumps. At times, the devices malfunctioned, but other times, teens were careless or took risks, the study authors wrote.

In the FDA study, appearing in the May issue of the journal Pediatrics , the reports of adverse events and deaths in adolescents using the pumps occurred from 1996-2005.

According to the analysis, some teens didn't know how to use the pumps correctly, dropped them or didn't take good care of them. There were two possible suicide attempts by teens who gave themselves too much insulin, according to the analysis.

"Parental oversight and involvement are important. Certainly teenagers don't always consider the consequences," said Dr. Judith Cope, lead author of the analysis.

The pumps are popular because they allow young people to live more normal lives, with far fewer injections.

And they're a growing segment of diabetes care, with $1.3 billion in annual sales worldwide, said Kelly Close, a San Francisco-based editor of a patient newsletter. She said 100,000 teenagers may be using them.

The FDA requires manufacturers to report injuries that could be linked to medical devices.

The authors analyzed reports from patients 12 to 21 years old. They emphasized that the reports aren't always clear about the cause of death or injury.

While some teenagers want to switch from injections to a pump to gain flexibility in their lives, doctors said problems such as a blocked tube can lead quickly to dangerous episodes of high blood sugar.

"In a matter of a few hours, all the insulin in the body disappears. Metabolically, the child starts to spiral out of control," said Dr. John Buse, the American Diabetes Association's president for medicine and science. Steve Sabicer, a spokesman for Minneapolis-based Medtronic Inc., which makes the top-selling insulin pump said the company stands behind the product's safety and "the many years of clinical evidence that support the benefits of insulin pump therapy."

What they are: Insulin pumps are the size of a cellphone and are worn on a belt or pocket. At programmed intervals, they send insulin into the body through a plastic tube with a small tip that inserts under the skin and is taped in place. Diabetics use them instead of regular insulin injections.

Who uses them: They are used by those with Type 1 diabetes, which accounts for about 5 to 10 percent of all diabetes cases and used to be called "juvenile diabetes."

Who is affected: Type 1 diabetes affects an estimated 12 million to 24 million people worldwide and occurs when the body attacks insulin-producing cells in the pancreas. Insulin regulates blood sugar levels, which when too high can lead to heart disease, blindness and kidney damage.

Cost: They cost about $6,000, and supplies run $250 a month. Many health insurers cover much of the cost.

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