Objective: To determine the frequency of fractures and associated factors in women with systemic lupus erythematosus (SLE).
Methods: Women with SLE (n = 304) completed this cross-sectional study conducted from 1996 to 2002. Self-reported fractures occurring after the diagnosis of SLE were evaluated. Hip and/or lumbar spine bone mineral density (BMD) was measured using dual-energy x-ray absorptiometry, and the results were expressed as BMD Z-scores. Multiple logistic regression analyses were performed to identify factors associated with fractures.
Results: Of the 304 women with SLE, 12.5% experienced fractures. Those with fractures had significantly lower BMD Z-scores at the hip (Fracture group -0.55 vs No Fracture group -0.14, group difference 0.41; 95% CI 0.04 to 0.78), but not at the lumbar spine (Fracture group -0.25 vs No Fracture group -0.18, group difference 0.07; 95% CI -0.43 to 0.57). Among women with fractures, 60.5% and 63.2% had normal BMD Z-scores (BMD Z-score > -1.0) at the hip and lumbar spine, respectively, and 50.0% had normal BMD Z-scores at both anatomical sites. In multiple logistic regression analysis, each year of disease duration (adjusted OR 1.11; 95% CI 1.05 to 1.17) and use of osteoporosis medications (adjusted OR 4.75; 95% CI 1.62 to 13.94) were significantly associated with fractures.
Conclusion: . Longer duration of SLE and use of osteoporosis medications were significantly associated with fractures. Although women with fractures had significantly lower BMD Z-scores at the hip, an unexpectedly high proportion of women with SLE having normal BMD Z-score experienced fractures following SLE diagnosis.