A large study in children and youth shows a three-fold increase in the risk of type 2 diabetes for those using prescription antipsychotics.

The use of antipsychotic drugs by children and youth has skyrocketed in the past decade. With this comes concern over the unwanted side effects of these prescription medications. A prime example, reported in a new study, is a three-fold increased risk of type 2 diabetes in people 24 years old and younger.

In adults, antipsychotic medications, such as risperidone, aripiprazole, and olanzapine, are already known to have metabolic side effects, including increased appetite, weight gain, and the risk of type 2 diabetes. The effect on younger people, however, is less clear.

“We know that antipsychotics cause diabetes in adults,” says Wayne A. Ray, Ph.D., a professor of preventive medicine at Vanderbilt University School of Medicine and co-author of the new study. “Given the increased use of antipsychotics in children and the increasing propensity for type 2 diabetes, we concluded the potential risk of this serious side effect should be examined in children.”

Using data from the Tennessee Medicaid program, researchers examined whether children and youth taking antipsychotic medications were more likely to develop type 2 diabetes.

The study, published online Aug. 21 in JAMA Psychiatry, included information on more than 28,000 children and youth between 6 and 24 years old who had received prescriptions for antipsychotics.

Throughout the study, researchers tracked patients who were taking these drugs to see how many developed type 2 diabetes—as indicated by either a doctor’s diagnosis or a prescription for diabetes medication.

The researchers found that children who had been using antipsychotics were three times more likely to develop type 2 diabetes, compared to a similar group of more than 14,000 patients taking other psychotropic medications.

The other drugs, Ray explains, are recognized alternatives for the same conditions treated with antipsychotics and are not known to increase the risk of type 2 diabetes. They include mood stabilizers like lithium, antidepressants, and medications for attention deficit hyperactivity disorder (ADHD).

“In any case, even if some [of the other psychotropics] do have metabolic effects, the risk of diabetes in the antipsychotic group was increased three fold relative to controls,” adds Ray.

This elevated risk for users of antipsychotic medications was apparent even during the first year of follow-up, although it was slightly lower. In addition, children and youth continued to have an increased risk of type 2 diabetes for up to a year after they stopped taking the antipsychotics.

It’s unclear why these medications increase the risk of type 2 diabetes. One of the side-effects of antipsychotic drugs is a greater appetite, which may cause patients to eat more. This can lead to increased body weight and insulin resistance, both of which are risk factors for diabetes.

“However, there may be direct medication effects that interfere with glucose metabolism and insulin production,” says Dr. Christoph Correll, a psychiatrist and researcher at Zucker Hillside Hospital in Glen Oaks, N.Y.

According to the Centers for Disease Control and Prevention, in 2003 only 3,700 people under the age of 20 were diagnosed with type 2 diabetes, a condition that affects adults at a much higher rate. The increased use of antipsychotic drugs among children and youth, however, could significantly affect that number.

Once used mainly to treat schizophrenia and other psychotic disorders, antipsychotic medications are now used to treat a wider range of conditions. “There has been growing use of antipsychotics in children for indications outside of psychosis—ADHD, conduct disorders, mood disorders,” says Ray.

In fact, a 2012 study in the Archives of General Psychiatry found that, between 1998 and 2009, prescriptions of antipsychotic medications jumped seven times in children and more than four times in adolescents.

Given the strengths of the new paper, Correll said doctors should carefully weigh the potential risks and benefits of antipsychotic treatment, especially in young patients—unless they have been diagnosed with conditions such as schizophrenia, for which the drugs were originally designed.

In addition, young patients should be monitored on an ongoing basis to look for metabolic side-effects. “Such monitoring should include, in children and youth, assessments of height and weight before initiating antipsychotic treatment and monthly,” says Correll, “as well as fasting blood work for blood sugar, hemoglobin A1C, and blood lipids before initiating antipsychotic treatment and at three months annually in adults, and likely six-monthly in children and youth.”