Biomechanical CT More Cost-Effective Than DXA for Osteoporosis Screening

A biomechanical computed tomography (CT) program used to screen for osteoporosis appears to be a cost-effective alternative to standard care dual-energy X-ray absorptiometry (DXA) scanning for all adults age ≥65 years, according to study results published in the Journal of Bone and Mineral Research.

Researchers used a 1-time biomechanical CT test to assess the accuracy and cost-effectiveness of this osteoporosis screening device for both men and women age ≥65. The study was based on a hypothetical cohort of 1000 patients who followed 2 mutually exclusive screening strategies that included a biomechanical CT program in year 1 or a usual-care strategy of DXA screening completed at recommended frequencies. The biomechanical CT strategy assumed 90% of the tested patients had CT scans yielding diagnostic-quality results, and of the patients that were categorized as high-risk, 50% were adherent to prescribed alendronate treatment for 2 years. The usual-care strategy included patients completing DXA at a typical screening frequency: 9.5% for women annually and 1.7% for men annually. To represent a no-screening strategy, a model for hip fracture rates was also included to provide a number of preventable hip fractures.

Overall, the biomechanical CT strategy proved to be more clinically beneficial and more cost-effective than the usual-care strategy and the no-screening model. Using the biomechanical CT strategy, 90% of women were screened and 21% tested positive for osteoporosis. Using DXA, 37.4% were screened and 12.5% tested positive for osteoporosis. For women, when using the no-screening model as a reference point, biomechanical CT prevented 5.5 hip fractures while DXA prevented 2.4 hip fractures. For men, biomechanical CT prevented 2 hip fractures and DXA prevented 0.2 hip fractures. When screening was restricted to patients at a 2-fold higher risk for hip fracture, prevented hip fractures also increased 2-fold with biomechanical CT, with a proportional increase in cost savings. Sensitivity and specificity increases in the biomechanical CT strategy had modest effects but indicated the importance of the proportions of patients screened in each strategy; the high testing rate of the biomechanical CT strategy was a large contributor to its clinical effectiveness.

Limitations of this study included its hypothetical cohort, despite outcomes being consistent with real-world data. In addition, the researchers generalized costs across the healthcare system and did not consider all clinical variables that impact hip fracture rates.

“[T]his modeling analysis indicated that a proposed ancillary [biomechanical CT]-based program for osteoporosis diagnostic screening — offered in a standing-order fashion to patients with a previously taken abdominal CT and without a recent DXA — appears to be cost-effective compared to usual care,” concluded the researchers.

Reference

Pisu M, Kopperdahl DL, Lewis CE, Saag KG, Keaveny TM. Cost-effectiveness of osteoporosis screening using biomechanical computed tomography for patients with a previous abdominal CT [published online February 19, 2019]. J Bone Miner Res. doi:10.1002/jbmr.3700

This article originally appeared on Endocrinology Advisor