Medications used to treat attention-deficit/hyperactivity disorder (ADHD) can have adverse cardiovascular effects, according to a new review. "ADHD medications are amphetamine-based drugs," Dr. James H. O'Keefe of Saint Luke's Mid America Heart Institute and the University of Missouri-Kansas City told Reuters Health by email. "They have frequent serious adverse effects, especially on the cardiovascular system." "Here in the U.S. we use 5- to 10-fold more ADHD drugs than European and Asian populations do," he said. "Because these drugs are so widely used and readily available, doctors and the general population have come to assume these drugs are safe." As sympathomimetic amines, drugs used to treat ADHD exert stimulant effects on the central nervous system by increasing levels of noradrenaline and dopamine in the prefrontal cortex, Dr. O'Keefe and colleagues note in the Journal of the American College of Cardiology. They also stimulate adrenergic receptors in the heart and blood vessels, leading to small increases in resting heart rate and blood pressure. A meta-analysis of 10 clinical trials reported resting heart rate increases averaging 5.7 beats/minute and systolic blood pressure increases of 2.0 mm Hg. In one placebo-controlled trial, methylphenidate use was associated with a four-fold increase in the odds of developing prehypertension in previously normotensive adults. ADHD medications have also been shown to adversely affect the autonomic nervous system by decreasing heart rate variability and increasing arterial stiffness. Safety studies in children have found the risk of adverse cardiovascular disease events to be more than twice as high among ADHD prescription medication users than among nonusers, and one case-control study found an increased risk of sudden cardiac death among children using methylphenidate or amphetamines for ADHD. Similar studies in adults have suggested no overall increase in cardiovascular risk with a history of ADHD medication use, although adverse cardiovascular disease event rates trended insignificantly higher in patients who recently started ADHD medications. Patients 65 years of age and older who take ADHD medications have an increased risk of new heart failure, especially within the first 90 days of initiation of the ADHD medication, and ADHD medications in this age group have been associated with acute coronary syndrome in the setting of normal coronary arteries and with stress-induced cardiomyopathy (i.e., Takotsubo cardiomyopathy). Among other ADHD treatments, exercise has immediate and long-term positive effects on behavioral and cognitive measurements without the increased risk of adverse cardiovascular events. Several studies have investigated the use of omega-3 polyunsaturated fatty acids for treating ADHD symptoms, with mixed results. High doses appear to provide the best results, while at the same time reducing the risk of major cardiovascular disease events. "Physicians and patients should be much more cautious and circumspect about the use of ADHD medications," Dr. O'Keefe said. "Prescribe ADHD drugs less often and more selectively. And emphasize natural therapies like daily exercise, counseling, and high-dose omega-3 for treating ADHD symptoms. When ADHD drugs are used, they should be prescribed at low doses and not for indefinite periods of time." He added, "Many adolescents and young adults who don't have ADHD use ADHD drugs for studying and test taking. In fact, a study shows that the waste water coming out of colleges has measurable increases in ADHD drugs and their metabolites during midterms and finals. These drugs are used very widely and their dangers are underappreciated." —Will Boggs MD Source
