Past research has suggested that children with ADHD are at higher risk of obesity than those without the disorder. Now, new research from the Johns Hopkins Bloomberg School of Public Health in Baltimore, MD, suggests that this increased risk may be a result of ADHD treatment, rather that the disorder itself.
ADHD (attention deficit hyperactivity disorder) is one of the most common childhood psychiatric disorders worldwide. There is no cure for the disorder, but stimulant medication is commonly used to help manage symptoms.
In recent years, studies have suggested there may be a link between ADHD and obesity. Last year, Medical News Today reported on a study revealing that males who have ADHD during childhood may be more likely to have a greater body mass index (BMI) in adulthood.
Such research has indicated that characteristics linked to ADHD, such as poor impulse control, can cause children with the disorder to develop poor eating habits that lead to weight gain.
But the researchers of this most recent study say that until now, no longitudinal studies have examined the association between stimulant medication for the treatment of ADHD and weight gain.
With this in mind, the team assessed whether stimulant use for the treatment of children and adolescents with ADHD had any impact on BMI. To do this, they used electronic health record data from the Gesinger Health System involving 163,820 children aged 3 to 18 years.
Stimulant use 'leads to rapid BMI growth later in adolescence'
Researchers say that the treatment of ADHD may increase the risk of obesity, rather than the disorder itself.
Results of the study, published in the journal Pediatrics, revealed that children with untreated ADHD - or ADHD that was treated without stimulants - had faster BMI growth in childhood, compared with children who did not have ADHD.
However, although children who had ADHD treated with stimulants had slower BMI growth in early childhood, they demonstrated rapid BMI growth later in adolescence than children without a history of ADHD or stimulant use.
Furthermore, the researchers found that the earlier stimulant use was initiated for children with ADHD, the stronger these effects were.
The research team says their findings support past research suggesting that children with ADHD are at higher risk of obesity. But they note that this outcome could come as a result of stimulant use and its impact on rapid BMI growth later in childhood and adolescence, rather than ADHD itself.
Summarizing the findings, the study authors write:
"The study provides the first longitudinal evidence that ADHD during childhood not treated with stimulants was associated with higher childhood BMIs.
In contrast, ADHD treated with stimulants was associated with slower early BMI growth but a rebound later in adolescence to levels above children without a history of ADHD or stimulant use. The findings have important clinical and neurobiological implications."
The researchers conclude that clinicians should be aware of the association between ADHD and obesity risk, particularly if children are being treated with stimulants.
They add that further research is warranted in order to create obesity prevention strategies for children with ADHD.
Last year, Medical News Today reported on a study from the Centers for Disease Control and Prevention (CDC) revealing that ADHD diagnosis in the US is increasing.
The study found that the number of children diagnosed with ADHD in 2011-12 was 2 million higher than the number of children diagnosed with the disorder in 2003-04. Furthermore, the research revealed that 1 million more children are taking medication for ADHD than previously.