"The Natural History of Weight Percentile Changes in the First Year of Life," a study published by JAMA in July, shows that growth charts used by pediatricians during the first year of a child’s life may not be the best approach to measuring height. Dr. Aaron Carroll, a professor of pediatrics at the Indiana University School of Medicine and co-author of the study, explains the issue with the faulty growth chart, and why many children don’t match up with its growing curve.
“What we found was that tons of children drop at least one or two lines over the course of the year… It implies to parents and doctors that we’re not giving kids enough to eat. That’s not the real problem in America," says Dr. Carroll.
“Still, as children grow up, some of them don’t get as tall as their parents expect. It’s called idiopathic short stature. ‘Idiopathic’ is one of those great medical terms. It means we’re not sure what caused it. Dr. Laurie Cohen recently wrote a paper offering some advice for parents who are wondering why their children are short. Dr. Cohen is the director of the Neuroendocrinology Program at Boston Children’s Hospital,” says host Barbara Lewis.
Cohen: A definition of somebody being short means they are more than two standard deviations below the average for their age and sex. Two standard deviations is about 2.3 percent. It’s a little bit less than 3 percent of the population. When somebody is defined as having ‘idiopathic short stature,’ that just means that we don’t know what the cause of their short stature is.
Ditmire: How do you find out what to determine if somebody does have idiopathic short stature?
Cohen: When we have a child who is short, we want to determine what the cause of that short stature may be, so we want to look at their growth pattern. Have they always been short? Have they been taller but just haven’t grown well so they are now short in this point of time? And we can decide that in four basic categories. There are going to be kids who are normally short because their family members are short. There are kids who are going to be short because they may have an underlying condition that limits their growth. This can include problems with bones or other syndromes. They may not have grown well because they have an underlying illness, either an illness where they can’t use nutrients. They’re either not taking enough in their diet or they aren’t absorbing them... Or they may have diseases that really limit how much they can grow because their body is working to take care of itself. So somebody who has a congenital heart disease… I should say bad congenital heart disease. Finally, there are kids who have endocrine conditions, so things like low thyroid hormone or lack of growth hormone.