Radiographic progression in patients with ankylosing spondylitis after 2 years of treatment with the tumor necrosis factor alpha antibody infliximab

Background

Anti-tumor necrosis factor therapy is clinically efficacious in patients with active ankylosing spondylitis (AS) and leads to improvement of spinal inflammation, as assessed by magnetic resonance imaging. It is unclear whether anti-tumor necrosis factor therapy has influence on chronic spinal changes in AS.

Objective

To analyze the effect of infliximab on the radiographic course of AS over 2 years.

Methods

Complete sets of lateral radiographs of the cervical and the lumbar spine were available from 82 patients from two sources: 41 patients (group 1) had been treated with infliximab (5 mg/kg/6 weeks) as part of a recent randomized controlled trial, and 41 patients (group 2) were part of the early German AS cohort (GESPIC), without controlled interventions. Radiographs were performed at baseline and after 2 years and were scored by the modified SASSS.

Results

Patients in the infliximab group were older, had a longer disease duration and more radiographic damage at baseline. The mean modified SASSS change was 0.4 (± 2.7) and 0.7 (± 3.4) for group 1 and group 2, respectively (P = not significant). Radiographic damage at baseline was a predictor for more radiographic progression. Patients with baseline damage who were treated with infliximab showed a trend for less radiographic progression. There were no correlations between clinical parameters and radiographic progression.

Conclusions

AS patients treated with infliximab showed somewhat less radiographic progression after 2 years. Patients with prevalent radiographic damage are prone to develop more damage over time. Infliximab may decelerate radiographic progression in such patients. Larger studies are needed to prove that anti-tumor necrosis factor therapy inhibits structural damage.