Active smoking is associated with the development of adverse events of biological therapy in patients with inflammatory bowel disease.

INTRODUCTION: Smoking has been associated with lower levels of anti-TNF agents, higher antibodies and a reduced response to anti-TNF in patients with inflammatory bowel disease (IBD). The aim of this study was to investigate the possible association between smoking and adverse events (AEs) of biologics in patients with IBD. MATERIAL AND METHODS: Consecutive IBD patients under biologics from a prospective, longitudinal registry of a tertiary center were included. A specially designed questionnaire including a wide range of AEs associated with biologics was also used. RESULTS: A total of 147 patients with IBD under biologics [median age (IQR) 46 (32.5-56) years, Crohn's disease (CD) 109 (74%), female 51 (35%), under combination with immunosuppressants 60 (41 %), under intensified biologic therapy 50 (34%), under anti-TNF 132 (89%), vedolizumab 11 (7.5%), ustekinumab 3 (2%)] who had completed the questionnaire forms for AEs were included. There were 52 (35%) active smokers and 33 (22.5%) ex-smokers. The prevalence of all AEs was 88% in smokers, 87% in ex-smokers and 79% in nonsmokers. Active smoking was significantly associated with the presence of arthralgias and skin rashes ( P = 0.01 and 0.002, respectively). These correlations were the same for the CD and ulcerative colitis (UC), except for arthralgias where there was a significant correlation only with CD ( P = 0.001). There were no significant associations between smoking and other AEs ( P > 0.05). CONCLUSION: Active smoking is associated with the development of dermatological manifestations (both in UC and CD) and arthralgias (in CD) in IBD patients under biologics.