Preliminary analysis for the ADD-BP study: Atypical femoral fractures and physical activity levels in bisphosphonate users.

OBJECTIVE

To investigate the relationship between physical activity levels and atypical femoral fractures (AFF) in bisphosphonate (BP) users.

METHODS

In the Assessing Daily-Activity-Level for Decisions on Bisphosphonate Prescription (ADD-BP) study, we retrospectively analyzed 27 women with AFF from five hospitals (2019-2023), categorized into BP (n = 18) and no-BP (n = 9) groups. Pre-injury physical activity was assessed via mobility aid usage, Long-Term Care Insurance System status, and independence in daily living.

RESULTS

Median ages were 77 years (BP) and 86 years (no-BP). In the BP vs. no-BP groups, 83.3% vs. 33.3% used no mobility aids, 11.1% vs. 22.2% used canes, and 5.6% vs. 33.3% used walkers. No BP users (0%) vs. 33.0% of no-BP users were housebound ; others were independent.

CONCLUSION

BP users with AFF exhibited higher physical activity levels than non-users, suggesting low activity may not elevate AFF risk in long-term BP use. These findings support the safety of extended BP therapy for fragility fracture prevention in less active patients. Future case-control studies are needed to confirm these results. This study was approved by the Fukushima Medical University Ethics Committee (REC2023-176).