|By Nancy Walsh, Staff Writer, MedPage Today
Published: September 29, 2011
Reviewed by Robert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco and
Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner
Image via WikipediaThe use of stimulant medications among children with attention deficit hyperactivity disorder (ADHD) continues to rise, particularly among adolescents, a nationally representative survey showed.
In 2008, these medications were used by 3.5% (95% CI 3.0 to 4.1) of children ages 18 and younger compared with 2.4% (95% CI 1.8 to 2.9) in 1996, according to Samuel H. Zuvekas, PhD, of the Agency for Healthcare Research and Quality in Rockville, Md., and Benedetto Vitiello, MD, of the National Institute of Mental Health in Bethesda, Md.
But among those ages 13 to 18, the rate of use increased by 6.5% annually, rising from 2.3% (95% CI 1.5 to 3.1) in 1996 and reaching 5% (95% CI 3.9 to 6.1) by 2008 (P<0.001), the researchers reported online in the American Journal of Psychiatry.
Some 9% of children ages 6 to 17 at some time have been diagnosed as having ADHD. Prescribing of stimulant medications rose sharply in the 1990s, and in the subsequent decade numerous new formulations were developed.
“As the market for ADHD medications has expanded, concerns have been raised about the possible misuse and abuse of stimulants, especially because the increase in ADHD diagnoses has been most marked in adolescents,” the researchers wrote.
To examine the patterns of use of drugs such as methylphenidate and amphetamines among young people, Zuvekas and Vitiello analyzed data from the Medical Expenditure Panel Survey, an ongoing report that follows trends in the treatment of psychiatric disorders.
They found that approximately 2.8 million children were using stimulants in 2008, a number that had risen by 3.4% each year since 1996.
The rate of use was highest among children ages 6 to 12, and that rate has held fairly steady over time — 4.2% (95% CI 3.2 to 5.2) were treated with stimulant medications in 1996, while 5.1% (95% CI 4.1 to 6.1) were on the drugs in 2008.
Children younger than 6 were the least common recipients of stimulant medications. Before 2004, yearly estimates for this age group were 0.3% to 0.4%, but thereafter fell to and remained at 0.1%, which was a significant decrease (t=3.71, P<0.001), according to the researchers.
Although a clinical trial in 2006 demonstrated efficacy for methylphenidate among preschool-age children, it also identified a higher incidence of adverse effects, and the current data showed that, in fact, ADHD medications are little used in the youngest children, Zuvekas and Vitiello pointed out.
Reflecting the gender predominance of ADHD, three times as many boys as girls were treated with stimulants (5.3% versus 1.6%).
Use was highest in whites, being 4.4% in 2008, compared with 3% of African Americans and 2.1% of Hispanics.
And although use was lower in minorities, it had risen notably from 1.9% and 0.7% in 1996 among African Americans and Hispanics, respectively.
This reflects a growing recognition of ADHD among groups that have often been underserved in mental health resources, while also suggesting that cultural barriers remain, according to the researchers.
Rates were low (1.3%) among children lacking health insurance, and those with public insurance were more likely to be on the medications than those with private insurance (OR 1.36, t=2.14, P=0.016).
Geography also influenced use, with 4.6% of children in the Northeast taking stimulants in 2008 compared with 1.6% of those living in the West.
The survey suggested that the majority of children with ADHD actually do not receive stimulant medications.
“This may not be unexpected, since about half of those diagnosed present with only mild symptoms and since other treatments, including psychosocial interventions and nonstimulant medications, are available,” the researchers explained.
Among other medications taken by small numbers of children were clonidine, guanfacine, and atomoxetine (Strattera).
The findings of this study should be interpreted in light of certain limitations, they noted, such as possible recall bias and underestimation of medication use, as well as a lack of validation for diagnoses in the survey.
Primary source: American Journal of Psychiatry
Zuvekas S, Vitiello B “Stimulant medication use in children: a 12-year perspective” Am J Psychiatry 2011; DOI: 10.1176/appi.ajp.2011.11030387.