The objective of this study was to assess the effects of rituximab on bone mineral density (BMD) in women with systemic lupus erythematosus (SLE) 1 year after treatment. Thirty active female SLE patients treated with rituximab were compared with 43 SLE women not treated with rituximab. BMD was measured using dual energy X-ray absorptiometry (DEXA) before initiating biologic therapy and after 1 year. The mean age was 38.5 ± 2.1 years; median disease duration was 7 years. In the rituximab group, after 1 year of follow-up, BMD at the femoral neck (FN) decreased from 0.980 ± 0.130 g/cm(2) to 0.809 ± 0.139 g/cm(2) (-17.4%; p=0.001). Similarly, BMD at the lumbar spine (LS) decreased from 1.062 ± 0.137 g/cm(2) to 0.893 ± 0.194 g/cm(2) (-15.8%; p=0.001). In control subjects, BMD at the FN decreased from 0.914 ± 0.193 g/cm(2) to 0.890 ± 0.135 g/cm(2) (-2.6%; p=0.001), and BMD at the LS decreased from 0.926 ± 0.128 g/cm(2) to 0.867 ± 0.139 g/cm(2) (-6.2%; p=0.09). After 1 year, SLE patients had lower BMD at both the FN and LS, but the loss was greater in postmenopausal patients who had received rituximab therapy.
Keywords: bone mineral density; rituximab; systemic lupus erythematosus.