MON-788 - Underestimation of Osteoporotic Fracture Risk in Patients with Chronic Glucocorticoid Use: A Retrospective Comparison of Clinical Fracture Risk Assessment Tools.

Background: Chronic glucocorticoid therapy increases the risk of osteoporotic fractures. Standard fracture risk assessment using FRAX may underestimate risk in these patients due to limited consideration of glucocorticoid dose. FRAX Plus, incorporating glucocorticoid dose, could improve risk stratification and early identification of high-risk patients.

Objective: To compare hip and major osteoporotic fracture risk classification using FRAX versus FRAX Plus in adults receiving chronic glucocorticoid therapy.

Methods: We conducted a retrospective, descriptive study of 198 adults (40–90 years) on systemic glucocorticoids ≥3 months (≥2.5 mg/day prednisone equivalent). Ten-year probabilities of hip and major osteoporotic fracture were calculated using FRAX and FRAX Plus. Patients were stratified into low, moderate, high, and very high risk. Associations with age, sex, prior fracture, and glucocorticoid dose were analyzed using chi-square tests (p < 0.05). Concordance between tools was assessed with Cohen’s κ coefficient.

Results: For hip fracture, FRAX classified 28% low, 42% moderate, 12% high, and 18% very high risk; FRAX Plus reclassified 18% to high and 22% to very high risk. Median age in very high-risk patients was 72 years (IQR 68–77) versus 48 in low-risk (IQR 46–54, p< 0.01). Prior fracture (OR 4.2, 95% CI 2.1–8.3) and glucocorticoid doses >7.5 mg/day (OR 3.8, 95% CI 1.9–7.2) were strongly associated with high-risk categories (p < 0.05). For major osteoporotic fracture, FRAX classified 72% low, 16% moderate, 12% high; FRAX Plus redistributed 46% to moderate and 14% to high risk. Concordance was substantial for hip fracture (κ=0.72) and moderate for major osteoporotic fracture (κ=0.40), confirming systematic underestimation by FRAX.

Conclusions: FRAX Plus identifies a larger proportion of patients at high and very high fracture risk compared with FRAX, particularly among those with prior fractures or higher glucocorticoid doses. Incorporating glucocorticoid dose improves risk stratification and may guide timely initiation of bone-protective therapy, potentially reducing fracture-related morbidity in this population.

*Unless otherwise noted, all abstracts presented at ENDO must not be released to the press or the public until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.*