Effectiveness of Bisphosphonates in Young Adults With Fragility Fractures: Representative Population-based Cohort Study.

Context: Fragility fractures in young adults present significant clinical challenges due to the limited evidence on the effectiveness of bisphosphonates in preventing subsequent fractures.

Objective: To evaluate the effectiveness of bisphosphonate therapy in reducing the fracture risk among premenopausal women with a history of osteoporotic fractures.

Design: A population-based retrospective cohort study was conducted using data from the National Health Insurance Service-National Sample Cohort in South Korea, covering the years 2003 to 2014.

Setting: A nationwide healthcare setting utilizing a representative cohort database.

Participants: Among 2087 premenopausal women with osteoporotic fractures, participants were propensity score-matched based on age and body mass index at a 1:3 ratio, resulting in 132 bisphosphonate users and 396 nonusers.

Intervention: Bisphosphonate treatment.

Main Outcome Measures: The incidence of osteoporotic fractures.

Results: Bisphosphonate users had a significantly lower risk of major osteoporotic fractures [hazard ratio (HR) 0.618, 95% confidence interval (CI) 0.396-0.963] compared to nonusers. Ibandronate users showed significant reductions in both major osteoporotic (HR 0.376, 95% CI 0.164-0.861) and nonvertebral fractures (HR 0.214, 95% CI 0.052-0.877). Also, longer duration of bisphosphonate use (≥180 days) was associated with a significantly lower risk of major osteoporotic and nonvertebral fractures (HR 0.528, 95% CI 0.300-0.929; HR 0.409, 95% CI 0.187-0.895, respectively).

Conclusion: Bisphosphonate therapy significantly reduces fracture risk in premenopausal women with previous osteoporotic fractures, especially at higher cumulative doses. These findings support considering bisphosphonates as a treatment option in premenopausal women at high risk of fractures.