Cigarette smoking has a dose-dependent impact on progression of structural damage in the spine in patients with axial spondyloarthritis: results from the GErman SPondyloarthritis Inception Cohort (GESPIC)

Recently, we demonstrated that smoking status itself is an independent predictor of radiographic spinal progression over 2 years in patients with axial SpA (axSpA).1 Here we report in more detail the relationship between tobacco smoking and development of structural damage in the spine in patients with axSpA with a focus on a dose-dependent association and a relationship between smoking and activity of systemic inflammation. In total, 210 patients with axSpA (115 with ankylosing spondylitis (AS) and 95 with non-radiographic axSpA (nr-axSpA)) from the GErman SPondyloarthritis Inception Cohort (GESPIC)1 ,2 were included. Detailed description of the patients and radiographs scoring has been reported elsewhere.1 In the current analysis, we used an extended syndesmophytes count, which included lateral views of the cervical and lumbar spine, and also antero-posterior views of the lumbar spine. Significant radiographic spinal progression was defined as (1) worsening of the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS) by ≥2 units after 2 years and (2) development of a new syndesmophyte or progression of existing syndesmophytes (formation of a bridging syndesmophyte from two single syndesmophytes) after 2 years. Smoking status and smoking intensity (non-smoker, 10 cigarettes a day and less, 11–20 cigarettes, and more than 20 cigarettes …