EFFECTS OF SMOKING IN PATIENTS WITH AXIAL SPONDYLOARTHRITIS RECEIVING TUMOR NECROSIS FACTOR INHIBITORS THERAPY

Abstract

Objective: The aim of this study was to examine the impact of smoking on axial spondyloarthritis (axSpA) patients taking tumor necrosis factor inhibitors (TNFi). Material and Method: Our study consisted of 211 patients who were diagnosed with axSpA and received TNFi treatment in the rheumatology outpatient clinic. The patients were evaluated retrospectively, cross-sectionally and grouped by intensity of smoking (pack-years). Those who smoked>20 pack-years were defined as heavy smokers. Groups were compared in terms of physical examination, laboratory values and disease evaluation indexes (Bath Ankylosing Spondylitis Metrology Index (BASMI), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), Ankylosing Spondylitis Quality of Life (ASQoL) and Beck Depression Inventory (BDI) scores. Mann-Whitney U and Spearman correlation analysis tests were used for data analysis Results: Comparison of the smoker (n=121) and non-smoker groups (n=90) revealed BASMI was lower in the non-smoker group (p=0.04). Smoking intensity correlated with BDI (r=0.323, p<0.001), BASDAI (r=0.257, p=0.005), BASMI components (lomber lateral flexion (LLF) (r=-0.303, p=0.001), cervical rotation (CR) (r=-0.232, p=0.012), and tragus wall distance (TWD) (r=0.27, p=0.003)). Multivariate analysis revealed an association between the pack-years of smoking and the BASMI [regression coefficient (B)=0.067, standard error (SE)=0.22, 95%CI=0.02, 0.10; p=0.003], baseline (B=pretreatment)-last value (L.=posttreatment) difference of BASFI [B=-0.063, SE=0.02, 95%CI=-0.10, -0.20; p=0.003], of BASDAI [B=-0.047, SE=0.02, 95%CI=-0.08, -0.007; p=0.026], ASQoL [B=-0.125, SE=0.04, 95%CI=0.04, -0.20; p=0.003]. In heavy smokers, significant worsening was found in LLFL (p=0.01), CRL (p=0.04), TWDL (p=0.001), BASFIL (p=0.035) and BASMIL (p=0.001). Significant differences were found in the baseline (B) and last (L) BASDAI (p=0.042), BASFIL (p=0.002), BASFIB-L (p=0.07) and BASMI (p=0.03) values in the nonradiograpic-axSpA group in heavy smokers, compared to the AS group. Conclusion: Our study showed that smoking, especially heavy smoking, has a negative effect in every phase of axSpA. Smoking intensity may correlate with reduced response to TNFi.