Abstract
Introduction
The purpose of this study was to clarify the incidence of steroid-induced osteonecrosis among different collagen diseases and to evaluate the predictive factors for steroid-induced osteonecrosis in a prospective MRI study.
Methods
We prospectively used MRI to study 337 eligible collagen disease patients requiring corticosteroid therapy and succeeded in examining 1199 joints (hips and knees) in 302 patients with MRI for at least one year starting immediately after the onset of corticosteroid therapy, a one-year follow-up rate of approximately 90%. The underlying collagen diseases included systemic lupus erythematosus (SLE) in 687 joints and a variety of other collagen diseases in 512 joints.
Results
Incidence of osteonecrosis was significantly higher in SLE patients than in non-SLE patients (37% versus 21%, p=0.001). Logistic regression analysis revealed that adolescent and adult patients had a significantly higher risk of osteonecrosis compared with pediatric patients (odds ratio [OR]=13.2), that high daily corticosteroid dosage (more than 40 mg/day) entailed a significantly higher risk of osteonecrosis compared with the dosage less than 40 mg/day (OR=4.2), that SLE patients had a significantly higher risk of osteonecrosis compared with non-SLE patients (OR=2.6), and that male patients had a significantly higher risk of osteonecrosis compared with female patients (OR=1.6).
Conclusion
These findings suggest that the incidence of steroid-induced osteonecrosis is different among underlying collagen diseases.
