A Swedish study finds that premature birth — even by as little as a few weeks — is linked to a greater likelihood of later being prescribed medication used to treat attention deficit hyperactivity disorder (ADHD). The study adds to previous research that has demonstrated that both severe prematurity and low birth weight are risk factors for ADHD.
ADHD impairs a person’s ability to concentrate and pay attention to things in their environment. They often have a hard time staying on task, and may also have difficulties with impulsive behavior. The disorder is usually treated with psychotherapy and psychiatric medications.
In the current study, Swedish researchers led by Karolina Lindström, M.D., analyzed a Swedish database of 1,242,459 children aged 6 to 19 years.
Since the researchers did not have access to actual diagnostic information about the children in their study, they used a stand-in for an ADHD diagnosis — whether the child was prescribed a medication typically used for ADHD. They found that 7,506 of the children in the study had received such a prescription for an ADHD medication.
Severe prematurity — being born between 23 and 28 weeks — was found to put an infant at the greatest risk for later developing attention deficit disorder. Babies born at this stage were more than two-and-a-half times more likely to later be prescribed a medication for ADHD.
But even mild prematurity — being born in weeks 37 or 38 — was found to confer an elevated 20 percent increased risk for later prescription of an ADHD medication.
Fifteen out of every 1,000 babies born at an extreme premature age and seven out of every 1,000 children born moderately premature (37-38 weeks) were prescribed ADHD drugs. Only six out of every 1,000 babies born between 39 and 41 weeks of pregnancy later received an ADHD prescription.
But being born a preemie isn’t the only factor that impacts the risk of a later attention deficit disorder diagnosis. Factors such as genetics and a mother’s smoking habits also play a role in a child’s risk of later developing ADHD.
The study is published in the latest issue of the journal Pediatrics.