Study: ADHD Drugs Likely Do Not Boost Heart Risk

Nov. 1, 2011 -- Medicines to treat ADHD (attention deficit hyperactivity disorder) do not seem to substantially increase the risk of serious heart problems or stroke in children and young adults. That’s the finding of a new study that included more than a million people.

When looking at the population as a whole, "these drugs don't appear to increase the risk of sudden cardiac death, heart attack, or stroke," says study researcher William O. Cooper, MD, MPH. Cooper is a professor of pediatrics and preventive medicine at Vanderbilt University in Nashville, Tenn.

Still, parents should discuss their child's personal risks with the child's doctor when making decisions about ADHD drugs, Cooper tells WebMD.

The study results drew mixed reactions from experts.

About 5.4 million children aged 4 to 17 have been diagnosed with ADHD, according to the CDC. ADHD medicines are prescribed for more than 2.7 million children in the U.S. each year to help deal with symptoms such as distraction and hyperactivity.

In the past, the use of ADHD drugs has triggered concern after reports of heart problems. In 2007, the FDA ordered makers of ADHD drugs to alert users to possible risks for heart-related problems. In 2008, the American Heart Association concluded that it was ''reasonable" for doctors to order an electrocardiogram on a child or young adult before prescribing ADHD medicine.

"It was a source of concern and confusion among parents and providers about what the risk might be," Cooper tells WebMD. "We set out to do the new study to try to do our best at answering what I considered to be a critical question.

"We do know that ADHD drugs increase heart rate and blood pressure," Cooper says. "But we don't know what effect that has in children."

The study findings appear online in the New England Journal of Medicine.

ADHD Drugs and Heart Risk: Study Details

Cooper and his team evaluated data from four health plans. They included plans in Tennessee, Washington state, California, and a national private insurance health plan.

In all, they looked at 1,200,438 children and young adults, aged 2 to 24.

They evaluated ADHD drugs in use during the study period, from 1986 to 2002. The follow-up lasted until 2005. The drugs included:

• methylphenidate (Concerta, Metadate, Methylin, Ritalin)
• dexmethylphenidate (Focalin)
• dextroamphetamines (Dexedrine, Dextrostat, Liquadd, ProCentra)
• amphetamine salts (Adderall)
• atomoxetine (Strattera)
• pemoline (Cylert)

For each patient on an ADHD medicine, the researchers selected up to two patients not on the medicine. They matched them by age and sex. The average age of the patients was 11. The follow-up averaged more than two years.

Next, the researchers looked to see if patients on medicine were more likely to have a serious problem, including  heart attack, sudden cardiac death, or stroke.