TNFi halts radiographic sacroiliitis progression in axial spondyloarthritis

Treatment with tumour necrosis factor inhibitors (TNFis) in patients with early axial spondyloarthritis (axSpA) appears to put brakes on radiographic sacroiliitis progression, according to a study.

The study included 301 axSpA patients from the German Spondyloarthritis Inception Cohort who had baseline plus at least one sacroiliac radiograph during a 10-year follow-up. The radiographs were scored according to modified New York criteria, while the sacroiliac sum score was calculated as a mean.

Researchers assessed TNFi use according to exposure in the current and/or previous 2-year radiographic interval. They included factors such as age, sex, symptom duration, HLA–B27 status, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), C-reactive protein (CRP), and nonsteroidal anti-inflammatory drugs (NSAIDs) intake in the analysis as potential confounders.

Of the patients, 166 had nonradiographic (nr-axSpA) and 135 had radiographic (r-axSpA) disease. The overall population contributed 737 radiographic intervals. 

Multivariable longitudinal generalized estimating equations analysis showed that receipt of ≥12 months TNFi in the previous interval was associated with a significant decrease in the sacroiliitis sum score (β, –0.09, 95 percent confidence interval [CI], –0.18 to –0.01). However, the same was not true for patients who received TNFI in the current interval (β, 0.05, 95 percent CI, –0.05 to 0.14). This effect was stronger in patients with nr-axSpA than in those with r-axSpA (β, –0.16, 95 percent CI, –0.28 to –0.03 vs β, –0.04, 95 percent CI, –0.15 to 0.07, respectively).

The findings indicate that TNFi may slow down radiographic sacroiliitis progression in patients with axSpA, although the effect can only be observed between 2 and 4 years after treatment initiation.