Overweight kids are more likely to sustain arm and leg fractures in car crashes than their thinner peers, a study out this month in the journal Injury Prevention shows.
The reasons why are not clear, Dr. Keshia M. Pollock of the Johns Hopkins Bloomberg School of Public Health in Baltimore, the lead researcher on the study, told Reuters Health. Heavy children's larger bodies may put them closer to the inside of the car, making for a more forceful impact, she noted, while there's also some evidence that overweight kids' bones may be more vulnerable to fractures.
"We don't believe it's strictly physiological. I think that there are multiple factors here that are important," Pollock said in an interview.
Among adults, she and her colleagues point out, occupants of cars involved in crashes who are obese are at greater risk of injury and death than those who are of normal weight. The types of injuries heavier adults suffer also are different, they add.
Differences
To investigate how body mass index might affect children's injury risk, the researchers analyzed data on 3,232 children 9 to 15 years old who were involved in motor vehicle accidents, with their parents driving. About a third of the children were overweight or obese.
Fifteen percent of children sustained moderate to severe injuries, such as concussions, fractures and abdominal injuries, the researchers found. While heavier children were no more likely to be injured in a crash than younger kids, their injuries were different.
Once the researchers adjusted for children's age, gender, car type, crash severity and other relevant factors, they found overweight and obese children were more than twice as likely as thinner kids to sustain injuries to their arms or legs.
The most common types of injury among leaner kids involved the pelvis, thigh bone and collar bone. This may be because heavier children have more shock-absorbing fat covering these body parts, the researchers say.
There is some evidence that obese and overweight people have lower levels of vitamin D, as well as calcium deficiency, which could lead to weaker bones, Pollock noted.
No matter what the factors involved are, the researcher commented, "We need to continue to keep kids appropriately restrained for their age and size." Children younger than 13 should always ride in the back seat, she added.
