Does Anti-TNF Therapy Cause A Less Significant Fall In Bone Mineral Density In Patients With Rheumatoid Arthritis?

Fifty eight patients with rheumatoid arthritis (RA) were assessed retrospectively to investigate whether anti-tumour necrotic factor (anti-TNF) therapy reduces bone mineral density (BMD) less significantly as assessed by dual-energy X ray absorptiometry(DXA) scan compared to those treated with conventional disease modifying drugs (DMARDs). Patients were divided into two groups: group A and B. Group A received anti-TNF therapy and group B received DMARDs. Patients who received bisphosphonate and other osteoporosis treatments such as hormonal replacement therapy were excluded. Changes in spine BMD and T-score between the baseline and the repeat DXA scan were assessed. Mean percentage change per year in spine BMD and T-score in each group were calculated. In group A, there was no significant reduction in spine BMD and T-score between baseline and repeat scan (P=0.353 and P=0.344 respectively). In group B, there was almost a significant reduction in spine BMD (P=0.058) and a significant reduction in spine T-score (P=0.013) between two scans. Although reduction of spine BMD and T score between baseline and repeat scan were more significant in group B, in terms of mean percentage change of spine BMD and T-score per year, there were no statistically significant differences (P=0.593 and P=0.185 respectively) between these groups.