The antipsychotic drugs that are increasingly being used to treat bipolar disorder, autism and other mental disorders in children may come with an increased risk of diabetes, a new study suggests.

Previous research has linked the so-called second-generation antipsychotics to an increased risk of diabetes in adults. And there’s been some evidence that the drugs can cause weight gain in children.

The new findings, published in the journal Pediatrics, add to concerns that the medications may ultimately lead to diabetes in some kids.

Using records from three U.S. health plans, researchers found that children and teens who started on an antipsychotic had four times the risk of being diagnosed with diabetes, versus kids not using any psychiatric medication.

They developed diabetes at a rate of just over three cases per 1,000 children per year. That compared with just under 0.8 cases per 1,000 among medication-free kids.

Second-generation antipsychotics include drugs such as Risperdal, known generically as risperidone, Zyprexa (olanzapine), Seroquel (quetiapine) and Abilify (aripiprazole).

The drugs are used to treat conditions like bipolar disorder, schizophrenia and irritability and aggression in children with autism. They are also sometimes given to children with attention-deficit hyperactivity disorder (ADHD), even though there’s no research evidence to support that.

And it’s the growing use of the drugs in kids - particularly for conditions in which the benefit is unclear - that makes the potential diabetes risk concerning, according to Dr. Jonathan Mink, chief of child neurology at the University of Rochester Medical Center in New York.

“These medications can be very helpful in certain settings,” said Mink, who is also part of a pediatric advisory panel to the U.S. Food and Drug Administration. In September, the panel recommended that the agency keep monitoring the risks of weight gain and diabetes in children on antipsychotics.

The drugs are often effective, for example, in managing aggressive behavior in children with autism. In other cases - like ADHD, Mink noted - the effectiveness, if any, has not been established.

Exactly why antipsychotics would lead to diabetes in some children is not clear. It’s known that they can spur weight gain, but Mink said that “it’s hard to argue that it’s just weight gain.”

In this study, kids on antipsychotics who developed diabetes were diagnosed an average of 4.5 months after starting the drug. That’s a short period of time, Mink noted. And it’s not clear, he said, exactly how the drugs could lead to diabetes in that time frame.

“The take-home from this study, to me, is that this (risk) is real,” Mink said. “It’s something we should take seriously.”

For the study, researchers led by Susan E. Andrade, of the University of Massachusetts in Worcester, combed through records for more than 74,000 five- to 18-year-olds enrolled in one of three health plans between 2001 and 2008.

Of those kids, 9,636 started on a second-generation antipsychotic during the study period. And out of the entire study group, 57 kids were diagnosed with diabetes.

Andrade’s team found that children on antipsychotics were at relatively higher risk of diabetes than those not on any psychiatric medication. On the other hand, their risk was not statistically greater compared with kids on antidepressants.

With antidepressants, the diabetes rate was just under two cases per 1,000 kids per year.

Antidepressants can cause weight gain. And there’s some evidence, Andrade’s team notes, that the drugs are related to diabetes risk - but studies have come to conflicting findings on that.

For now, Mink said that parents of children on antipsychotics should be sure their doctor regularly checks their child’s weight and blood sugar, to detect any signs of trouble early.

And if your child’s doctor recommends an antipsychotic, Mink said, don’t hesitate to ask questions - including whether there are any alternative treatments, and what the plan will be for monitoring your child for side effects.

U.S. researchers have found that children’s use of antipsychotics increased by 65 percent from 2002 to 2009, primarily through prescriptions for teenagers.

From fall 2009 to spring of this year, 1.9 million prescriptions of Abilify alone were dispensed to patients under 18, including even 875 prescriptions for toddlers younger than two, according to FDA research.

SOURCE: Pediatrics, online November 21, 2011.