Canadian health authorities briefly removed Adderall from the market in 2005, and the U.S. Food and Drug Administration (FDA) required that ADHD drugs carry a "black box" label warning and a patient guide.
Subsequently, the American Heart Association stated it would be "reasonable" to give kids screening electrocardiograms before starting them on stimulant medication.
"This really added to the concern and confusion among families and health care providers," Cooper said.
To try to settle the question, Cooper and his colleagues analyzed data on 1.2 million children and young adults aged 2 to 24 enrolled in four large health plans around the United States. This was called a meta-analysis.
"We compared those currently using ADHD medicines to those not using these medications to look at their risk for sudden death, heart attack and stroke," Cooper explained. The medications included methylphenidate (Ritalin, Concerta), dexmethylphenidate (Focalin), dextroamphetamine (Dexedrine), amphetamine salts (Adderall), atomoxetine (Strattera) and pemoline (Cylert).
The authors concluded that there was really no raised risk of heart problems with these medications, although they also acknowledged the possibility of up to an 85 percent increased risk.
That's because the large size of the study and the rarity of events made it difficult to track the relative increased risk.
"Placing that in context, even if there was a doubling, the absolute risk would be very, very low," Cooper said.
The findings are similar to several reports published after the FDA's safety review was compiled, the authors said.
For his part, Pliska said EKGs [electrocardiograms] might still be helpful in identifying some children with cardiac defects.
And Cooper agreed that some children may have underlying heart disease
All rights reserved