Kaiser Study Finds ADHD Meds Safe for the Heart
(EmaxHealth) Oakland, CA - More than 1.5 million US adults take a medication for the treatment of attention-deficit/hyperactivity disorder or ADHD. Because the drugs can increase heart rate and blood pressure, concerns have been raised about their cardiovascular safety. However, a new study, published in the December 12th online edition of the Journal of the American Medical Association finds that stimulant medications such as Ritalin, Adderall, and Vyvanse do not appear to be associated with an increased risk of serious cardiovascular events in young and middle-aged adults.
Stimulant drugs are prescribed to help users to focus thoughts and ignore distractions. They are used in children, adolescents and adults who are having ADHD symptoms that are affecting school, work and home life and are effective in about 70% to 80% of patients.
Laurel Habel PhD, of Kaiser Permanente Northern California, and colleagues analyzed data using electronic healthcare records from four sources - OptumInsight Epidemiology, Tennessee Medicaid, Kaiser Permanente California, and the HMO Research Network. Over 150,000 individuals between the ages of 25 and 64 were identified who had filled a prescription for an ADHD treatment such as methylphenidate (Ritalin), amphetamine, atomoxetine (Strattera), or pemoline (Cylert). These persons were matched with a healthy control that had not been prescribed a medication for ADHD.
The rate of cardiovascular events such as myocardial infarction (MI or heart attack), sudden cardiac death, or stroke was significantly lower in current users of the drugs compared with non-users. The findings are consistent with another study of children between the ages of 2 and 24 that was reported last month.
The authors do note that there were several limitations to the study, including the use of electronic pharmacy records to determine medication use, possible misclassification of some of the endpoints/outcomes, and the limited ability to adjust for diagnosis (some medications may have been prescribed for other conditions, such as narcolepsy).
"A modestly elevated risk cannot be ruled out, given limited power and a lack of complete information on some potentially important risk factors and other factors related to use of these medications," Habel and colleagues wrote.
But Philip Shaw MD PhD of the National Human Genome Research Institute points out in an accompanying editorial that the absolute risk increase is still likely to be small. Assuming the upper limit of the confidence interval for the rate ratio, he notes, the increase would equate to 0.19 additional events per 1,000 person-years for younger adults (25 to 44) and 0.77 additional events for those 45 to 64.
"Now there is solid evidence -- perhaps even some heartening news -- that physicians can use to address concerns about cardiovascular risk," Shaw wrote. But, he added, "the study does not obviate either the need for a thorough history and examination of all patients prior to starting any ADHD medications or the need for ongoing evaluations. Psychostimulants have many noncardiovascular adverse effects that must be monitored, including weight loss, appetite suppression, and insomnia."
Habel L, et al "ADHD medications and risk of serious cardiovascular events in young and middle-aged adults" JAMA 2011; DOI: 10.1001/jama.2011.1830.
Shaw P "ADHD medications and cardiovascular risk: some heartening news" JAMA 2011; DOI: 10.1001/jama.2011.1866.
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