FRI0473 ASSESSING THE CLINICAL RELEVANCE OF BONE DENSITOMETRY SCREENING IN PATIENTS UNDER 40 YEARS OF AGE: INDICATIONS AND RESULTS
Authors: Laura Chadwick, Deepti Challa, Sankalp Tripathi, Kiran Kumar Putchakayala
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> Guidelines for the diagnosis and treatment of osteoporosis in patients under the age of 40 years are lacking. The International Osteoporosis Foundation (IOF) working group has recommended dual-energy X-ray absorption (DXA) screening should only be performed in this age group if patients have an associated chronic disease such as inflammatory bowel disease (IBD) in conjunction with a vertebral fracture or multiple fractures elsewhere.<sup>1</sup> For these patients, a T-score of &lt;-2.5 can be used to diagnosis low BMD but the term osteoporosis may not be appropriate and there is minimal evidence supporting the use of bisphosphonates (BPs). <h3>Objectives</h3> In patients under 40 years of age undergoing DXA screening, to determine (1) the indication and (2) the DXA results (age adjusted Z score and standard T score), in order to conclude whether DXA screening in this group was appropriate and relevant for making meaningful treatment decisions. <h3>Methods</h3> Clinical details for all DXA scans requested for patients less than 40 years of age were obtained from the Mid Cheshire Hospital NHS Trust radiology department for a 6 month period from July to December 2018 inclusive. Descriptive data was produced regarding basic patient demographics, DXA indication and DXA results in the form of Z- and T-scores at the neck of femur (NOF) and spine. <h3>Results</h3> In total, 35 patients under the age of 40 years underwent DXA screening in the defined time period. The mean age of patients was 30.5 years (s.d. 6.0) and 24 patients (69%) were female. The youngest patients were 19 years. Regarding indications, only two patients (6%) were appropriate for DXA screening according to the IOF suggested guidelines, both of whom had vertebral fractures. Twenty seven patients (77%) had an established diagnosis of a disease known to cause OP but no history of fracture. Regarding results, at the NOF and spine respectively mean Z-scores were -0.77 (s.d. 1.19) and -0.96 (s.d. 0.97), and mean T-scores were -0.88 (s.d. 1.19) and -0.945 (0.93). Only three patients (9%) had Z- or T-score of &lt;-2.5; two patients who had a history of thoracic vertebral fracture, and a patient with high steroid use for IBD but no fracture history. <h3>Conclusion</h3> The majority of patients aged less than 40 years referred for DXA screening are being referred due to associated diagnoses with no history of fracture, not in keeping with IOF recommendations. Of the 33 patients with no history of fracture, only one patient (3%) had a T-score consistent with low BMD. There is little evidence to support bisphosphonate use in this group. We therefore conclude that DXA screening in patients less than 40 years should be reserved for those with a history of fracture. <h3>References</h3> [1] Ferrari, S. et al. (2012). Osteoporosis in young adults: pathophysiology, diagnosis and management. Osteoporosis Int. 23:2735-2748 <h3>Disclosure of Interests</h3> None declared