Bone fragility and atypical femoral fractures in SLE: role of disease activity, infection, and treatment.

INTRODUCTION

To determine the incidence and risk factors of fragility fractures and atypical femoral fracture (AFF)-related events in patients with systemic lupus erythematosus (SLE) receiving long-term glucocorticoid (GC) therapy.

MATERIALS AND

METHODS

A retrospective analysis was conducted of 170 SLE patients followed from 2016 to 2023. Data on GC use, bisphosphonate (BP) therapy, bone-related events, and clinical characteristics were collected. Risk factors for fragility fractures and AFF-related events, including localized periosteal thickening (LPT), were analyzed using multivariate logistic regression.

RESULTS

Although the median daily dose of prednisolone decreased over time, 82.9% of patients still met the criteria for pharmacologic intervention for GC-induced osteoporosis in 2023, and most continued to receive > 5 mg/day of GC. The median duration of BP therapy was 10.4 years, with 69 patients maintaining BP treatment throughout the observation period (median, 12.5 years). Fragility fractures and AFF-related events occurred in 7.6% and 5.8% of patients, respectively. Fragility fractures were independently associated with SLE flares and infection-related hospitalizations, whereas AFF-related events were significantly associated with prolonged BP use.

CONCLUSION

Despite a gradual reduction in GC dosage, many patients with longstanding SLE remain at elevated risk for fractures. The comparable frequencies of fragility fractures and AFF-related events highlight the clinical relevance of both complications. The prevention of SLE flares and infections may contribute to lowering the risk of fragility fractures. In addition, careful monitoring for AFF/LPT is warranted in patients receiving long-term BP and GC therapy.