Late Breaking Abstract - Oral corticosteroid (OCS) risk predictor for osteoporosis

Introduction: OCS use is associated with risks of adverse outcomes, including conditions like osteoporosis; a model to estimate individual risks from OCS use would be useful. Objective: Develop a model to evaluate osteoporosis risk in patients with asthma. Methods: A retrospective cohort study of eligible adults with asthma (≥2 Rx for asthma medication) and ≥2y of follow-up flanking a random asthma consult (index date). Primary outcome was time to osteoporosis diagnosis (in those with no prior history). Two Cox models were used to model known osteoporosis risk factors, which were identified from published literature and selected for inclusion based on significance. The model was evaluated in 75% of the patients and validated in the remaining 25%. Results: Overall, 123,695 patients met all criteria for the osteoporosis risk model (4091 with osteoporosis; 119,604 without). Risk factors included in the prediction model included OCS (both pre- and post-index total exposure), age, sex, BMI, comorbidities, smoking, and GINA Step. The model validation showed a consistently higher predicted osteoporosis risk among patients with additional post-index OCS use compared to those with no post-index use. In an example patient, 20y osteoporosis risks were 23.18%, 24.45%, and 25.78% for 0, 500, and 1000 mg average annual post-index OCS doses, respectively (Figure). Conclusion: Mean annual OCS predicts an increased risk of osteoporosis in patients with asthma.