• Harms are just as important as benefits

    Absolutely frightening editorial on a new study in JAMA Pediatrics on the dangers from radiation in scans in children. It’s called “The Harm in Looking”, and here’s the intro (emphasis mine):

    As a result of the recent growth in the field of diagnostic imaging, the US population has been subjected to a 7-fold increase in exposure to medical radiation since the 1980s. Concerns over radiation-induced malignancy continue to mount in the popular and scientific press.

    In this issue of JAMA Pediatrics, Miglioretti et al provide valuable data on the use of computed tomography (CT) in pediatrics and the associated radiation exposure in children during the period from 1996 to 2010; the data were derived from a large research network of health maintenance organizations in the United States. The authors used a random sample of CT scans to calculate radiation dosages and to estimate attributable risks of malignancy. In a similar investigation of adults, they found that, in 2010, an average of just over 1 diagnostic imaging test involving radiation was performed per enrollee, for an average radiation exposure of 2.34 mSv (the equivalent of over 200 posterior-anterior chest radiographs).

    Using the same database, Miglioretti et al present several noteworthy findings: (1) the overall use of CT in pediatrics increased 2- to 3-fold during this time period, (2) substantial variability existed in the radiation doses used, and (3) projections of the risks of malignancy with the use of certain scans are higher than previously reported (eg, 1 in 300 girls younger than 5 years of age who undergo an abdominal/pelvis CT scan will develop a subsequent solid tumor).

    If doctors were about to get a CT scan of my daughter, and they told me that the scan gave 1 in 300 such girls a solid tumor at some point, I’d think really, really, really hard about whether that scan was necessary. One CT is equal in radiation to 200 chest x-rays?!?!? Here’s a table of stuff we shouldn’t get, but do:


    Go read the whole thing. Now. And bring this up the next time someone tries to get a CT on your kid.


    • An interesting, and concerning, additional point is the.evidence from studies (e.g., Natale et al, Arch Ped Adolescent Med 2012 166(8):732-7) that parental anxiety may be one of the drivers of unnecessary CT scans — especially white parents. I hope we can find other ways to quell parent and patient anxiety, to stem this troubling overuse.

    • A couple of years ago I went to the ED with classic, classic appendicitis symptoms. I must have had a half dozen people explain to me why I didn’t need a CT. I was absolutely fine with the plan, but they kept reassuring me. It actually started to get pretty funny. They all knew that I was a physician, but I don’t know if that increased their desire to explain the situation or not. I did get an ultrasound to rule out ovarian pathology even though it was obvious, to me anyway, that the problem was bowel. The ED doc told me that they had a program going to try to reduce CT use for the diagnosis of appys.

    • Aaron, as a pediatrician, how much of a factor do you think fear of litigation plays in the clear overuse of scanning in this population (i.e., if you can be sued up till the child is 18, wont that increase your propensity to image at the margin?) by some doctors?

      Combined with parental anxiety and many younger docs reluctance to trust “just” a physical and HPI, that could be driving this trend (admit preemptively I have no proof of this)

    • Aaron, if you’ve never listened to this summary of the issue you’re missing out: