Do patients with larger body sizes undergo more CT exams?

Background: Overweight and obese patients are known to have more diseases than normal weight individuals, but it is currently unknown if there is higher utilization of computed tomography (CT) exams among those with larger body sizes.
Aims: To examine whether patients with larger body sizes undergo more CT exams and by how much more.
Methods: Using the recently described T-shirt size assessed from the lateral and transverse dimensions in CT localizer radiographs as a surrogate for body size, patients were classified into seven T-shirt sizes (XXS, XS, S, M, L, XL, XXL). This multi-center study analyzed over one million CT exams performed in 256 medical institutions in the USA to assess the frequency of CT use in patients of different body sizes.
Results: It was found that patients with larger body sizes (L, XL, XXL sizes) underwent 2.5-3.5 times more CT scans in the chest region and 7.8-17.7 times in the abdominopelvic region as compared to those with smaller body sizes (XXS, XS, S sizes). Further, the patients with extra-large body sizes (XL and XXL) underwent 4.6-9.9 times scans in the chest region and 39.2-187.8 times scans in the abdominopelvic region as compared to those with extra-small body sizes (XXS and XS).
Conclusions: Our first-of-its-kind study demonstrating the manyfold use of CT in patients with large body sizes may be interesting for healthcare policy planning and developing guidelines for allocating resources for obese patients.
(© 2023. The Author(s), under exclusive licence to Royal Academy of Medicine in Ireland.)