Almost 40% of children and adolescents taking ADHD medications were found to be suffering from bone loss, according to a new report, but researchers are cautioning against changing clinical practices based on these early findings.
A new study estimates that 38% of children and adolescents taking certain medications for attention-deficit/hyperactivity disorder (ADHD) may suffer from bone loss.
However, while there is evidence that these medications may result in “real and non-trivial” differences in the bone density of subjects taking ADHD medications compared to those that did not, researchers recommend additional studies before the findings are applied to clinical practice.
The new study, published in the Journal of Pediatric Orthopaedics found that bone mineral density was significantly lower in children who took medications such as Ritalin (methylphenidate) to treat ADHD.
Jessica Rivera, MD, senior study author with the US Army Institute of Surgical Research, says the study’s findings are not meant to imply that ADHD medications should not be prescribed, or that bone scans should be performed before prescribing. What is does mean, she says, is that more research is needed to determine the full impact of this class of medications.
“No medication comes without some side effect and it is always possible there are side effects we don't entirely know about,” Rivera says. “This study shows an association between the medication and changes in bone density but does not indicate a causation. The difference is very important as this is not a study which in and of itself should change practice.”
Rivera says more research is needed to determine whether clinical practice should change as a result of the new findings, but pediatricians should still consider all the effects of these medications before prescribing them.
“Pediatricians and parents/guardians should be aware that the association exists and consider this into the risk/benefit discussion when considering these medications,” she says.
Three groups of data collected between 2005 and 2010 as part of the National Health and Nutrition Examination Survey (NHANES) were studied, for a total of 5315 children and adolescents aged 8 to 17 years. Bone mineral density (BMD) was tested in 3 areas-total femur, femoral neck, and lumbar-and low BMD caused by age, gender, race, and socioeconomic factors were ruled out. Medications were considered, specifically the use of ADHD medications, but the study did not differentiate doses or the length of use.
The study found that participants that were taking ADHD medications had lower BMD than those who were not taking ADHD medications. In fact, 38.3% of children taking ADHD medications had BMDs within the osteopenic range compared to 21.6% of children not taking these medications.
The Centers for Disease Control and Prevention estimate that of the 6.4 million children aged 4 to 17 years who have been diagnosed with ADHD, 3.5 million-almost 50%-take psychotropic medications to control the disorder. There has been concern for some time that these medications-specifically methylphenidate-can affect weight early in treatment and height with longer term use. Common side effects include abdominal pain and nausea, as well as loss of appetite. Given that many of these children take ADHD medications during the period of peak bone accrual, negative impacts on bone density are particularly concerning.
Attention-deficit/hyperactivity disorder medications may affect BMD via the gastrointestinal side effects they cause, therefore altering dietary intake of calcium, the study authors suggest.
“Children on ADHD medications tend to have lower caloric intake compared with nonmedicated counterparts, placing micronutrient and macronutrient intake at risk,” according to the study. “Although the current literature supports that there are only temporary aberrations in growth velocity at the initiation of ADHD medication treatment, what effects this temporary interruption in normal growth has on potential bone mass accrual is not known. However, interrupted bone mass accrual has long-term implications. Fifty percent of one’s peak bone mass is gained during childhood and adolescence; and 92% to 95% of one’s maximum bone mass is developed by age 18 years.”
Attention-deficit/hyperactivity disorder medications may also impact bone density by blocking catecholamine reuptake in the central nervous system, resulting in increased stimulation of peripheral signaling of catecholamine receptors and direct action as receptor ligands, according to the study.
The study did not take into account how long the study subjects were taking ADHD medications or the dosage, nor did it consider the diet and activity of the children who suffered from bone loss.
Researchers note that in addition to encouraging further research on the effects of ADHD medications on bone health, these findings also open the door to improved nutritional counseling for children and adolescents taking ADHD medications.