Impact of cumulative exposure to high-dose oral glucocorticoids on fracture risk in Denmark: a population-based case-control study.

We examined the effect of cumulative exposure to high doses of oral glucocorticoids on fracture risk. Compared to short-course users (daily dose ≥ 15 mg + cumulative < 1 g), heavy users (daily dose ≥ 15 mg + cumulative dose ≥ 1 g) had the highest risk of fracture. These patients should be monitored for fracture management strategies. PURPOSE: The effect of cumulative exposure to high daily doses of oral glucocorticoids on fracture risk remains debated. We therefore aimed to examine the hip fracture risk associated with short courses and heavy use of high-dosed oral glucocorticoids. METHODS: We conducted a population-based case-control study using the Danish National Health Service data, 1996-2011. Cases were those aged ≥ 18 years who sustained a hip (primary outcome) fracture (n = 81,342). Vertebral and forearm fractures were considered in secondary analyses. Controls (matched 1:1) were those without a fracture. Average daily dose (DD) and total cumulative dose (CD) were calculated among current oral glucocorticoid users. Among patients with a high daily dose (DD ≥ 15 mg), we identified short-course users as those with a CD < 1 g and heavy users as those with a CD ≥ 1 g. We estimated adjusted odds ratio (adj.OR) of fracture with current glucocorticoid use compared to never-use, using conditional logistic regression. RESULTS: A high DD (≥ 15 mg) and high CD (≥ 1 g) were independently associated with an increased hip fracture risk (adj.OR 2.5; 95% CI 2.2-2.9; adj.OR 1.6; 95% CI 1.5-1.8, respectively). However, the risk was substantially increased among heavy users (DD ≥ 15 mg and CD ≥ 1 g: adj.OR 2.9; 95% CI 2.5-3.4) as compared to short-course users (DD ≥ 15 mg and CD < 1 g: adj.OR 1.4; 95% CI 1.1-1.9). Associations were stronger for vertebral fractures, yet little association was identified for forearm fractures. CONCLUSION: Among patients receiving a high DD (≥ 15 mg), heavy users (≥ 1 g CD) showed the most substantial increase in hip fracture risk. Among those receiving high DD, a threshold of 1 g CD may identify heavy users that are candidates for focused fracture management services.

Effectiveness of Oral Bisphosphonates in Reducing Fracture Risk Among Oral Glucocorticoid Users: Three Matched Cohort Analyses.

The benefit of oral bisphosphonates in reducing fracture risk in glucocorticoid-induced osteoporosis is controversial. We aimed to estimate the effectiveness of oral bisphosphonates in reducing fracture risk in a cohort of new chronic oral glucocorticoid users. We created three matched cohorts using health care administrative data from Ontario, Canada. We included residents aged 66 years and older initiating chronic oral glucocorticoids (≥450 mg prednisone equivalent and ≥2 glucocorticoid prescriptions within a 6-month window) between January 1998 and September 2014. Exposed patients were those who initiated an oral bisphosphonate (alendronate, etidronate, or risedronate) within the first 6 months of starting chronic oral glucocorticoid therapy. Exposed cohorts (3945 alendronate, 5825 risedronate, and 8464 etidronate) were each matched 1:1 to unexposed patients on glucocorticoid exposure, fracture risk factors, and propensity score. We examined incident hip (primary outcome), vertebral, forearm, and humerus fractures using Cox proportional hazard models. Alendronate (hazard ratio [HR] = 0.46, 95% confidence interval [CI] 0.25-0.80) and risedronate (HR = 0.58, 95% CI 0.36-0.90) were associated with reduced hip fracture risk. Alendronate (HR = 0.52, 95% CI 0.39-0.68), etidronate (HR = 0.59, 95% CI 0.48-0.73) and risedronate (HR = 0.47 95% CI 0.36-0.60) were associated with reduced vertebral fracture risk. No risk reduction in forearm or humerus fractures was apparent for any bisphosphonate. Among older chronic glucocorticoid initiators, all oral bisphosphonates reduced vertebral fracture risk, yet only alendronate and risedronate reduced hip fracture risk. Results were similar between men and women. We provided compelling evidence that early initiation of oral bisphosphonates during chronic oral glucocorticoid therapy is beneficial to prevent osteoporotic fractures. © 2017 American Society for Bone and Mineral Research.