ARTHRITIS & RHEUMATISM Vol. 64, No. 5, May 2012, pp 1388–1398 DOI 10.1002/art.33465 © 2012, American College of Rheumatology Baseline Radiographic Damage, Elevated Acute-Phase Reactant Levels, and Cigarette Smoking Status Predict Spinal Radiographic Progression in Early Axial Spondylarthritis Denis Poddubnyy, 1 Hildrun Haibel, 1 Joachim Listing, 2 Elisabeth Ma ¨rker-Hermann, 3 Henning Zeidler, 4 Ju ¨rgen Braun, 5 Joachim Sieper, 1 and Martin Rudwaleit 6 Objective. To assess prospectively the rates and to explore predictors of spinal radiographic progression over 2 years in a cohort of patients with early axial spondylarthritis (SpA). Methods. Two hundred ten patients with axial SpA from the German Spondyloarthritis Inception Co- hort were selected for this analysis based on the avail- ability of radiographs at baseline and after 2 years of followup. Spinal radiographs were scored by 2 trained readers in a blinded, randomly selected order according to the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS). Spinal radiographic progression was defined as worsening of the mean mSASSS by >2 units over 2 years. Results. Among the patients with axial SpA, 14.3% showed spinal radiographic progression after 2 years (20% of those with AS and 7.4% of those with nonradiographic axial SpA). The following parameters were independently associated with spinal radiographic progression: presence of syndesmophytes at baseline (odds ratio [OR] 6.29, P < 0.001), elevated levels of markers of systemic inflammation (for the erythrocyte sedimentation rate, OR 4.04, P  0.001; for C-reactive protein level time-averaged over 2 years, OR 3.81, P  0.001), and cigarette smoking (OR 2.75, P  0.012). These associations were confirmed by multivariate lo- gistic regression analysis. No clear association with spinal radiographic progression was observed for HLA– B27 status, sex, age, disease duration, Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Functional Index, presence of peripheral arthritis, enthesitis, psoriasis, treatment with non- steroidal antiinflammatory drugs, or treatment with disease-modifying antirheumatic drugs at baseline. Conclusion. The presence of radiographic damage at baseline (syndesmophytes), elevated levels of acute- phase reactants, and cigarette smoking were all inde- pendently associated with spinal radiographic progres- sion in patients with early axial SpA. The term axial spondylarthritis (SpA) refers to patients with radiographic sacroiliitis fulfilling the mod- ified New York criteria for ankylosing spondylitis (AS) (1) and patients with nonradiographic axial SpA (i.e., patients without definite radiographic changes in the sacroiliac joints) (2). Both groups of patients can be The German Spondyloarthritis Inception Cohort has been supported by the German Federal Ministry of Education and Research (BMBF) (grant FKZ 01G19946), as part of the German Competence Network in Rheumatology. Because funding by BMBF was reduced according to schedule in 2005 and discontinued in 2007, complemen- tary financial support was obtained from Abbott, Amgen, Centocor, Schering-Plough, and Wyeth. Since 2010, additional support has been provided by the BMBF through the ANCYLOSS and ArthroMark projects. 1 Denis Poddubnyy, MD, Hildrun Haibel, MD, Joachim Sieper, MD: Charite ´ Universita ¨tsmedizin, Campus Benjamin Franklin, Berlin, Germany; 2 Joachim Listing, PhD: German Rheumatism Re- search Centre, Berlin, Germany; 3 Elisabeth Ma ¨rker-Hermann, MD: Horst Schmidt Kliniken, Wiesbaden, Germany; 4 Henning Zeidler, MD: Medizinische Hochschule Hannover, Hannover, Germany; 5 Ju ¨r- gen Braun, MD: Rheumazentrum Ruhrgebiet, Herne, Germany; 6 Martin Rudwaleit, MD: Evangelisches Krankenhaus Hagen-Haspe, Hagen, Germany. Dr. Ma ¨rker-Hermann has received consulting fees, speaking fees, and/or honoraria from Abbott, Wyeth, Roche, Chugai, MSD, and Pfizer (less than $10,000 each). Dr. Braun has received consulting fees, speaking fees, and/or honoraria from Abbott, MSD, Pfizer, and UCB (less than $10,000 each). Dr. Rudwaleit has received consulting fees, speaking fees, and/or honoraria from Abbott, Bristol-Myers Squibb, MSD, Pfizer, and UCB (less than $10,000 each). Address correspondence to Joachim Sieper, MD, Rheuma- tology, Medical Department I, Charite ´ Universita ¨tsmedizin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203 Berlin, Germany. E-mail: joachim.sieper@charite.de. Submitted for publication February 27, 2011; accepted in revised form November 1, 2011. 1388