Current smoking status is a strong predictor of radiographic progression in early rheumatoid arthritis: results from the SWEFOT trial

Abstract

ObjectivesTo study clinical predictors for radiographic progression after 1 year in an early rheumatoid arthritis (RA) trial.MethodsIn the SWEFOT trial population, disease modifying antirheumatic drug (DMARD) naïve RA patients started methotrexate; 3-month responders (DAS28 <3.2) continued (n=147), while non-responders were randomised to addition of sulfasalazine+hydroxychloroquine (n=130) or infliximab (n=128). X-rays were scored by the Sharp-van der Hejde score (SHS) method and radiographic progression was defined as a ≥5 increase after 1 year. Potential baseline predictors of radiographic progression were tested using multivariable logistic regression, adjusted for potential confounders.Results79 of 311 patients with available radiographs at baseline and follow-up had radiographic progression. The following baseline parameters were independent predictors of radiographic progression at 1 year: baseline erosions (adjusted OR=2.29, 95% CI 1.24 to 4.24), erythrocyte sedimentation rate (adjusted OR per tertile increase=1.72, 95% CI 1.12 to 2.65) and C-reactive protein (adjusted OR per tertile increase=1.52, 95% CI 1.03 to 2.26). Current smoking was an independent predictor of radiographic progression (adjusted OR=2.17, 95% CI 1.06 to 4.45). These results remained after further adjustment for treatment strategy. Three-dimensional matrix including current smoking status, erosions and C-reactive protein tertiles showed a 12–63% risk gradient from patients carrying none compared with all predictors. Rheumatoid factor (RF)/anti-cyclic citrullinated peptide (anti-CCP) positivity did not significantly predict radiographic progression using SHS increase ≥5 as cut-off. In a secondary exploratory analysis using cut-off >1, both RF and anti-CCP positivity were significant predictors in the unadjusted, but not the adjusted analyses. The other parameters also remained significant using this lower cut-off.ConclusionsIn addition to previously described predictors, we identified smoking as a strong independent risk factor for radiographic progression in early RA.Trial registration numberNCT00764725.

Changes in the anticitrullinated peptide antibody response in relation to therapeutic outcome in early rheumatoid arthritis: results from the SWEFOT trial

“…Anti-cVim seroreversion was also evaluated using a logistic regression model, where radiographic progression was dichotomised according to SHS increase >1 or >5, respectively,13 adjusted for baseline DAS28, baseline erosions, current smoking status, sex and EULAR response at 3 months. Therapeutic response according to EULAR criteria was dichotomised into responders and non-responders.…”

Smoking Behavior Changes in the Early Rheumatoid Arthritis Period and Risk of Mortality During Thirty‐Six Years of Prospective Followup

“…AP 1 = attributable proportion due to interaction, test 1; AP 2 = attributable proportion due to interaction, test 2. 26 Sparks et al such as interstitial lung disease (35)(36)(37). These factors are associated with an increased risk of mortality among patients with RA, perhaps explaining the differential effect for RA on mortality compared to the general population (38,39 .…”

Etiology of Rheumatoid Arthritis: A Historical and Evidence-Based Perspective

“…Preliminary evidence suggests that cigarette smoking can induce expression in the lungs of the enzymes responsible for citrullination of various proteins, thus creating antigen targets of autoantibodies that are tightly associated with RA [ 18 , 19 ]. Smoking is also associated with resistance to successful treatment of RA and more rapid disease progression [ 20 ]. Thus, smoking cessation should be viewed as part of both prevention and treatment of RA.…”