Computed Tomography Use and Indications in Children With and Without Chronic Health Conditions.

OBJECTIVE: The objective was to evaluate the cumulative frequency and indications for computed tomography (CT) examinations during childhood in a large cohort of young patients aged 1-21 years (henceforth "children") followed longitudinally in an integrated health care system. STUDY DESIGN: This was a retrospective cohort study. Children born and continuously enrolled in a US integrated health care system from January 1, 1996 to April 30, 2016 were followed to assess CT exposure using Current Procedural Terminology codes. Indications for imaging were determined using International Classification of Diseases codes at the time of the CT examination, and chronic illnesses were identified using the pediatric complex chronic conditions classification system. RESULTS: Among 30,491 children who underwent 43,072 CT examinations, 2380 (8%) had chronic illness. Despite shorter follow-up among children with chronic illness [8.9 years (standard deviation [SD] = 5.8) vs 12.0 years (SD = 6.1)], they were more likely to undergo multiple CTs per patient compared with those without: mean = 2.6 (SD = 3.6) vs 1.1 (SD = 0.8); P < .001. A total of 28% of children with chronic illness vs 6% without underwent 3 or more CT examinations. Children with chronic illness were most commonly imaged for neurologic indications (40%, n = 2467) and children without for trauma (42%, n = 15,629). CONCLUSIONS: In children undergoing CT examinations, over 20% of children underwent multiple CT examinations. Children with chronic illness more frequently received 3 or more CT examinations compared to children without chronic illness. Further research is needed to determine when the benefits of CT imaging outweigh radiation risks to optimize patient outcomes.