Rise in kids on ADHD drugs ‘concerning’: UBC study
More than four per cent of elementary schoolchildren in B.C. are taking stimulant medications for attention-deficit hyperactivity disorder, or ADHD, the highest in two decades, UBC researchers have found.
The increase in prescriptions to children ages six to 12 — a neardoubling since 2000 — is “unexplained and concerning” since there’s no evidence that longterm benefits outweigh potential harms, says UBC’s Therapeutics Initiative. Between five and nine per cent of schoolchildren are said to be affected by ADHD, according to B.C. Children’s Hospital, which offers experts and resources.
Alan Cassels of the Therapeutics Initiative co-wrote the latest therapeutics letter (posted on Monday but dated January/February). He said studies in other countries show similar prescription increase trends in the past few decades.
“The use of such drugs continues to climb, but no one seems to be able to explain it,” he said, adding that marketing probably plays a role as does limited access to alternatives such as psychotherapy.
“What is clear is that there is no epidemic of depressed or hyperactive children. Drugs are easily available, quick and relatively cheap,” he said, adding they may also meet parent and child goals faster than therapy. Research has shown that parents and teachers often observe improvements in hyperactive, impulsive and disruptive kids who are medicated.
But Cassels said class size is an unexplored avenue for research: Will teachers be able to manage children with certain problems better, now that B.C. has mandated smaller classrooms? Will that stem the increase in prescribing of ADHD medications?
Researchers have observed a relationship between birth months and stimulant use. The youngest children in classrooms, those born between September and the end of each calendar year, are much more likely to be prescribed ADHD medications.
In a previous Therapeutics Initiative study, researchers found that boys were 41 per cent more likely to use the medications and girls 77 per cent more likely, if they were born between September and December, compared to boys and girls born in January. That study “strongly suggests that teachers, parents, and physicians are medicalizing a social, rather than a medical problem,” the Therapeutics Initiative bulletin states.
Studies in other countries, including the U.S., Iceland, Germany and Denmark, have also shown that the youngest students in classrooms are most likely to be prescribed stimulants for ADHD. That means parents should consider holding back children from school if they were born toward the end of the year, so they don’t have to struggle, Cassels said.
THE DOWNSIDE
While the Therapeutics Initiative has twice published letters of concern on the topic, Cassels said there does not seem to be any change in the ever-rising prescribing of stimulants to children. Yet, the group has warned, “children are particularly vulnerable to harms of long-term drug therapies and there should be a higher level of evidence of effectiveness to justify their use. ADHD stimulants can increase heart rate and blood pressure and disturb heart rhythms. The medications can disrupt sleep patterns, inhibit appetite and stunt growth.”
In the medical journal Pediatrics last week, researchers demonstrated a potential harm associated with stimulants: unintentional and intentional over-exposures to stimulant medications. From 2000 through 2014, there were 156,365 calls to U.S. poisoncontrol centres over swallowing of ADHD pills.
The study, among children 19 years of age and younger, said the rate of exposures reported to poison-control centres increased 71.2 per cent from 2000 to 2011, but then fell by 6.2 per cent between 2011 and 2014. But, overall, there was a still a large increase in calls or reports of possible overdose exposures during the study period.
The wrong dose was said to be the cause of more than 40 per cent of calls while intentional overdoses accounted for more than half. Most cases were not serious, but three deaths were reported. Medications most often involved were Ritalin, Concerta, Adderall, and dexedrine. (The Poison Control Centre in B.C. has not done a similar study, but does take calls about stimulant overdoses).
The authors of the American study said that the increasing number of poison-control calls is associated with trends in diagnosis and prescribing, and “exposures associated with suspected suicide or medication abuse and/ or misuse among adolescents are of particular concern.”
The Therapeutics Initiative is funded by the B.C. Health Ministry. Its evidence-based bulletins are peer-reviewed; the current letter was read by 75 experts before publication.