Background/Purpose:
Inhibition of tumor necrosis factor alpha (TNFi) and interleukin-6 receptor (IL6Ri, tocilzumab) are among the most potent therapeutic strategies in patients with rheumatoid arthritis (RA) and have shown to retard structural bone damage. Comparative longitudinal studies on the impact of TNFi or IL-6i on periarticular bone damage in RA, however, have not been performed.
Methods:
Observational study on 54 patients with RA receiving TNFi (N=25) or IL6Ri (N=29) in combinaton with methotrexate over one year. All patients received baseline and one-year follow-up examination of the 2nd – 4th metacarpophalangeal and wrist joints for presence of erosions and osteophytes using high-resolution peripheral quantitative computed tomography (HR-pQCT). Erosions and osteophytes were quantified both numerically and metrically at baseline and one year follow-up. Demographic and disease specific characteristics such as age, gender, disease duration and -activity were recorded.
Results:
Both cohorts were comparable for age, gender, disease duration and –activity, autoantibody status as well as baseline bone damage. At baseline 185 erosions (MCP:N=136; wrist_N=49) and 340 osteophytes (MCP:N=248; wrist_N=92) were detected in the 29 patients of the IL-6i group and 123 erosions (MCP:N=84; wrist;N=39) and 270 osteophytes (MCP: N=176; wrist: N=94) were detected in the 25 patients of the TNFi group. Erosion numbers significantly increased in the MCPs (+0.321mm³, t(83)=-2.92, p=0.004) and tended to increase in the wrist joints:(+0.13mm³, t(48)=-0.52, p=0.096) in the TNFi group, whereas they remained constant in IL-6i treated patients both in wrist and MCP joints. No significant volumetrical change of erosive changes of erosions was observed in either group. Osteophyte numbers (TNFi:+0.27mm, t(175)=-6.99, p<0.001; IL6i:+ 0.1mm, t(245)=-3.49, p=0.001) and size (TNFi:+0.19mm, t(174)=-7.01, p<0.0001; IL-6i:+0.08mm, t(247)=-3, p=0.003) in the MCP joints significantly increased in both groups. In the wrists, osteophytes increased both in size (+0.9mm, t(96)=2.49, p=0.015) and numbers (+0.19mm, t(93)=-3.14, p=0.002) in the TNFi group while remaining constant in size and increasing in numbers (+0.185mm, t(91)=-3, p=0.004) in the IL-6i group.
Conclusion:
This study suggests that IL-6Ri allows an even better control of structural bone damage than TNFi in patients with erosive RA. Furthermore, the observation that HR-pQCT allows detecting structural progression in TNFi treated RA patients is important and indicated that high-level imaging technology allows very detailed analysis of changes of bone composition in RA patients, which could be valuable to improve the monitoring of strucrural effects of anti-rheumatic drugs.
Disclosure:
S. Kraus,
None;
M. Englbrecht,
None;
J. Rech,
None;
R. Kocijan,
None;
G. A. Schett,
None;
S. Finzel,
None.
« Back to 2013 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/comparative-longitudinal-analysis-of-periarticular-bone-structure-in-patients-treated-with-methotrexate-in-combination-of-either-tnf-blockers-or-tocilizumab/