By Dr Ananya Mandal, MD
A new study looked at nearly 150,000 adults taking drugs for attention deficit hyperactivity disorder (ADHD) and found that the medications do not increase the risk for heart attack, stroke, or sudden death from heart-related causes.
The research, published online Monday in the Journal of the American Medical Association, comes just over a month after the same investigators found that the drugs likely do not raise the risk for serious heart problems in children and young adults, based on their study of more than 1.2 million young users.
Drugs for ADHD are being taken by millions of children and adults in the U.S. These include stimulants such as Adderall,Concerta, Metadate, Methylin, Ritalin, or the non-stimulant Strattera to treat ADHD symptoms such as hyperactivity, impulse control, and trouble focusing.
While the results are reassuring they do not rule out a modest increase in risk associated with their use, says researcher Laurel A. Habel, a research scientist with the Kaiser Permanente Division of Research in Oakland, Calif. She said, “With any drug there are potential risks, and these drugs can increase blood pressure… But if there is an increase in [heart-related] events, our study suggests that it is slight.”
“These studies provide an important piece of the puzzle that we have not had,” says Vanderbilt University professor of pediatrics and preventive medicine William O. Cooper, who led the study in children.
A total of 150,359 medication users aged 25 to 64 from four sites were each matched with two nonusers at the same study site with respect to birth year, sex, and calendar year. Participants were followed up starting in 1986 at one site and ending in 2005 at all four sites. During the study period there were 1,357 heart attacks, 296 sudden deaths from cardiac arrest, and 575 strokes recorded. Use of ADHD drugs was not associated with an increased risk of any of these three outcomes, even among users with prior heart disease.
In an editorial published with the study, ADHD researcher Philip Shaw, of the National Institutes of Health concluded that there is now little evidence to support this recommendation. American Heart Association past-President Robert Bonow, professor of medicine at Northwestern University in Chicago, says the two studies were well designed and well executed and he agrees that the findings are reassuring.
“There has been something of a dark cloud over these drugs with regard to their impact on the heart,” Bonow said. “These findings should put many of these fears to rest, but it is still important to know an individual patient’s risk. Patients with heart disease and those who have a high risk for heart disease need to be monitored if they take these drugs.”
The federal Agency for Healthcare Research and Quality and the FDA paid for the study.