In patients with early ankylosing spondylitis (AS), effective suppression of inflammation with tumor necrosis factor inhibitor (TNFi) therapy decreases radiographic progression of the disease, according to the results of an observational cohort study published in Arthritis & Rheumatology.
The investigators sought to explore the effect of TNFi treatment and inflammation control on radiographic progression in patients with early AS over 4 years. A total of 215 patients with early AS (symptom duration <10 years) were enrolled in the study. Of these, 135 participants were treated with TNFi and 80 participants were treated with nonsteroidal anti-inflammatory drugs (NSAIDs) in the control group. Radiographic progression was evaluated by 2 blinded readers using modified Stoke Ankylosing Spondylitis Spine Score (mSASSS). Control of inflammation was inferred by measuring time-averaged serum C-reactive protein (CRP) levels between 2 radiologic assessments.
Participants in the TNFi group had longer disease duration, higher baseline CRP levels, and higher Bath Ankylosing Spondylitis Disease Activity Index compared with controls. The time-averaged CRP over radiographic intervals was significantly lower in the TNFi group vs the control group (0.27±0.30 mg/dL vs 0.61±0.68 mg/dL, respectively; P <.001).
The overall mean mSASSS change over the 2-year interval was 1.30 units. In the multivariable model, which was adjusted for age, smoking status, baseline CRP level, and presence of baseline syndesmophyte, the TNFi group demonstrated less change in mSASSS over the 2-year period (β=–0.90; 95% CI, –1.51 to –0.29). When time-averaged CRP level was included, however, this significantly affected the change in mSASSS (β=1.02; 95% CI, 0.32-1.71) and decreased the estimated group difference (β=–0.52; 95% CI, –1.17 to 0.14). NSAID indices in both groups were not linked to time-averaged CRP level or mSASSS change.
The investigators concluded that although these results need to be replicated in future studies, they appear to support the view that early effective suppression of inflammation with TNFi therapy might inhibit pathologic new bone formation in patients with early AS.
Park JW, Kim M, Lee JS, et al. Impact of tumour necrosis factor inhibitor versus non-steroidal anti-inflammatory drug treatment on radiographic progression in early ankylosing spondylitis: its relationship to inflammation control during treatment [published online July 8, 2018]. Arthritis Rheumatol. doi: 10.1002/art.40661