For years, researchers and health policy experts have been charging that psychiatric medications aren’t adequately tested in children – and a new study gives some powerful ammunition to that critique.
The study, from Pediatrics, looked at clinical drug trials between 2006 and 2011, involving five conditions that cause the greatest “disease burden” for children, as measured by a rating that counts the total years of healthy life lost to disability.
In high-income countries like the United States, three of the five conditions with the highest disease burden among kids were psychiatric disorders: depression, bipolar disorder and schizophrenia.
But of the drug studies to treat those conditions, disproportionately few involved children.
The lack of trials is troubling because children and adults don’t necessarily respond to medication in the same way. With psychiatric drugs, that’s a potential problem both for physical reasons – and for psychological and developmental ones.
For all kinds of medications – not just psychotropics – smaller, undeveloped bodies may absorb and metabolize drugs differently. Often, doctors have to guess what constitutes a safe and effective dose based on studies that were done only in adults.
But the lack of studies on psychotropic drugs is also problematic because many psychiatric disorders manifest differently in adults and children.
For example, an antidepressant that effectively treats depression symptoms in adults may not tame the irritability that’s more characteristic of childhood depression.
And years after SSRI antidepressants went on the market, having been tested in adults, the Food and Drug Administration warned that the drugs appeared more likely to increase the risk of suicidal thinking in youth and young adults with major depression than in older people with the condition. Shortly afterward, Britain’s National Health Service told doctors to avoid prescribing any antidepressants to children under 18 for the same reasons.
In the U.S., many psychiatric drugs given to children are prescribed “off-label” – meaning the FDA has only officially approved the drug for some other use or some other age group.
The Pediatrics study findings highlight a major factor driving off-label prescribing to children. To gain approval to market a drug to a particular age group or for a particular condition in the U.S., pharmaceutical companies must submit evidence to the FDA showing the drug is safe and effective for that population of patients.
But the study found that while the drug industry funded the majority of drug trials in adults, nonprofits and the government funded most drug trials in children. That was the case despite recent laws passed in the U.S. trying to incentivize the drug companies to conduct more pediatric drug trials.
Industry-funded trials have been widely criticized as biased, but since nonprofit and government funds are limited, a lack of industry investment in pediatric drug trials may be resulting in fewer studies overall, the study’s authors suggest.
Other researchers have expressed concerns that the quality of pediatric drug trials is sub-par in terms of study design and other indicators, compared to those in adults. This study didn’t find major quality differences, though.
As for the how the proportion of pediatric trials compared to the relative burden of disease in kids, here’s how it stacked up for the three psychiatric disorders studied.
Children accounted for 12% of the disease burden of depression in high income countries and 17.3% in low and middle-income countries. But just 3.4% of depression drug studies involved kids.
The relationship for schizophrenia was even worse. Children made up 30.8% of disease burden, but just 4.6% of schizophrenia drug trials were conducted on kids.
Bipolar disorder had a slightly more equitable ratio: The disease burden was 19.3%, and 13.5% of the drug studies were pediatric.
Do you find these numbers troubling? Or are they just the result of reasonable barriers to pediatric drug research, like concerns about the ethics of testing potentially unsafe drugs on children?
And, given the overall lack of pediatric studies, what are doctors and parents to do when faced with a troubled child? Does the paucity of studies mean they should avoid medication altogether?