Many children suffer from attention-deficit/hyperactivity disorder, or ADHD, but a new study suggests a link between children with ADHD and weight gain as they enter teenage years.

The study, which was released online on Monday, and which will appear in print in the journal Pediatrics later this spring, suggested that children suffering from ADHD, and especially those taking medications to help keep their symptoms under control, were more likely to experience weight gain. The study also suggests that the medications used to diminished the symptoms of ADHD could be responsible for the the increased susceptibility to weight gain.

Author of the study, Dr. Brian Schwartz, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health in Baltimore said, “The reason we think it is more likely to be the drugs than the diagnosis is because the earlier the drugs were started and the longer the drugs were used, the stronger the effects. If you agree with the reports that stimulants may be over-prescribed, then this is another important cost of that over-treatment — kids who have dramatic changes in their growth trajectories during and after the treatment.”

The study included the examination of more than 160, 000 records belonging to children between the ages of 3 and 18, with some being tracked for as many as 12 years. The children included in the study typically had three body-mass index measurements recorders over the span of the study. The body-mass index is a measurement of body fat based on a person’s height-to-weight ratio, and the body-mass index measurements were used to assist in determining projected growth over an extended span of time.

The study found that approximately 8 percent of children had been diagnosed with ADHD, and of those, nearly 7 percent had been prescribed stimulant-type medications. Children diagnosed with ADHD who did not receive  medications were typically larger than their peers as early as age 10, whereas those who took stimulants to ease their symptoms did not show signs of weight gain until the ages of 15 to 18. However, while those who received medications were less likely to experience weight gain until later on in their teen years, they were more likely to gain an increase amount of weight than those who did not receive stimulant-type medications.