Bone mineral density in systemic lupus erythematosus women one year after rituximab therapy

Abstract

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/cm² to 0.809 ± 0.139 g/cm² (−17.4%; p = 0.001). Similarly, BMD at the lumbar spine (LS) decreased from 1.062 ± 0.137 g/cm² to 0.893 ± 0.194 g/cm² (−15.8%; p = 0.001). In control subjects, BMD at the FN decreased from 0.914 ± 0.193 g/cm² to 0.890 ± 0.135 g/cm² (−2.6%; p = 0.001), and BMD at the LS decreased from 0.926 ± 0.128 g/cm² to 0.867 ± 0.139 g/cm² (−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.