The tendency to treat childhood ADHD with drugs has levelled off in the UK, following a steep rise over the past 20 years, research published in the BMJ Open has revealed.
However, when kids with attention deficit and hyperactivity disorder (ADHD) are treated with drugs, their treatment lasts for much longer than that of their European or US peers, the findings have shown.
"Although the prevalence and incidence of ADHD drug use in children have substantially increased during the past two decades, it seems that it may have reached a plateau recently," the authors concluded.
"Our study indicates a turning point in the patterns of ADHD drug prescribing in children in the UK."
The researchers based their findings on an analysis of Clinical Practice Research Datalink (CPRD) records, relating to children up to the age of 16 who had been prescribed at least one drug to treat ADHD between 1992 and 2013.
The researchers analysed the data to estimate trends in ADHD prescribing patterns among children and the length of treatment for those diagnosed with the condition.
During this period, 14,748 children under the age of 16 (85% of them boys) were given at least one prescription for an ADHD drug, with methylphenidate accounting for 94% of all prescriptions.
More than half (58%) of the children received their first prescription between the ages of six and 11. Around 4% were five years old when they were first prescribed an ADHD drug.
The use of these drugs in this age group soared from 1.5 per 10,000 children in 1995 to 50.7 per 10,000 in 2008, after which it seemed to level off at 51.1 per 10,000 children by 2013.
The rate of new prescriptions has a similar pattern over the same timeframe, reaching 10.2 per 10,000 children in 2007, but subsequently falling to 9.1 per 10,000 in 2013.
These patterns may reflect the impact of National Institute for Health and Care Excellence guidelines issued in 2008, suggest the researchers.
UK prescribing rates for ADHD drugs are considerably lower than they are in many other countries, the researchers point out.
They are 10 times lower than in the US, up to five times lower than in Germany, and four times lower than in the Netherlands.
Nevertheless, the course of treatment tends to be longer than in these countries, the published evidence indicates. More than three out of four UK children (around 77%) were still being prescribed ADHD drugs one year after diagnosis and 60% were still on treatment two years later, the figures show.
The probability of stopping ADHD drugs within six years seemed to be higher in 11- to 15-year-olds than it was in six- to ten-year-olds, the data revealed, which may indicate that treatment is being stopped too early among young adults, say the researchers.
This is an observational study, and the researchers point out that their analysis cannot determine the causes behind the prescribing patterns they found.