Fracture rate associated with quality metric-based anti-osteoporosis treatment in glucocorticoid-induced osteoporosis

Summary Anti-osteoporosis medication (AOM) use in patients exposed to glucocorticoids is thought to reduce fractures. We found post-menopausal women using glucocorticoids for at least 90 days who also used an AOM within 90 days had 48 % fewer fractures by 1 year and 32 % fewer fractures by 3 years compared to non-AOM users. Introduction The purpose of this study is to explore the effectiveness of adherence to quality measures by estimating the effect of anti-osteoporosis medication (AOM) initiation within 90 days after chronic (≥90 days) glucocorticoid (GC) therapy on osteoporotic fracture. Methods A new-user cohort was assembled using the MarketScan databases between 2000 and 2012. Included patients were female, age ≥50 at GC initiation, had a first GC fill daily dose ≥10 mg and persisted for at least 90 days. During a 365-day baseline period, patients were excluded for prior GC or AOM (bisphosphonate, denosumab, teriparatide) use, fracture, or cancer diagnosis. Initiators of an AOM in the 14 days pre- or 90 days post-GC fill were characterized as AOM users; those without, AOM non-users. Follow-up began 91 days after GC fill with patients followed until fracture, loss of continuous enrollment, initiation of AOM by AOM non-users, or end of study period. A propensity score was estimated for AOM receipt using all measured covariates and converted to a stabilized inverse probability of treatment weights (IPTW). Weighted hazard ratios (HR) and associated 95 % confidence intervals (95 % CI) were estimated using weighted Cox proportional hazard models. Results Of the 7885 women eligible for the study, 12.1 % were AOM users. AOM use was associated with lower fracture incidence: weighted HR of 0.52 (95 % CI 0.29, 0.94) at 1 year and weighted HR of 0.68 (95 % CI 0.47, 0.99) at 3 years. Conclusions AOM initiation within 90 days of chronic GC use was associated with a fracture reduction of 48 % at 1 year and 32 % at 3 years.