Cigarette smoking has a very detrimental effect on the course of Crohn’s disease (CD) while data on ulcerative colitis (UC) are conflicting with some studies suggesting a potential protective effect. Smoking trends have changed dramatically changed over the last decades in the United Kingdom with the introduction of a smoking ban in public buildings and the advent of e-cigarettes. We aimed to describe current smoking rates in IBD patients compared to the general population and to ascertain any effects of smoking on disease course.Methods
Self-reported smoking status was elicited in consecutive IBD out-patients and clinical data (phenotype, demographics, treatment history, current disease status) were extracted from the electronic hospital patient record. Office of national statistics 2015 data for the general population were used as the comparator.Results
Of 375 patients (mean age 44.7 years; mean disease duration 10.7 years) 50% suffered from CD, 42% from UC and 8% from IBD-U. Current drug exposure included: 157 mesalazine, 109 thiopurine, 8 methotrexate, 44 infliximab, 34 adalimumab, 6 Vedolizumab and 45 patients were on steroids. Current disease activity was remission (42.4%), mild (41.1%), moderate (14.9) and severe (1.6%). Of 200 ever cigarette smokers 144 had stopped and 56 continued cigarette use, while of 30 ever e-cigarette users 14 had stopped and 16 continued. All e-cigarette users had previously smoked cigarettes and 10 had stopped smoking completely after e-cigarettes. Crohn’s disease patients were more likely to smoke cigarettes (19.9% vs 8.1%) or e-cigarettes (4.1% vs 3.4%) compared to UC/IBD-U patients (p=0.026).Results
Infliximab use was more common in cigarette smokers (13.2%) and e-cigarette users (21.4%) vs non-smokers (11.2%); p=0.016. Adalimumab use was more common in cigarette smokers (16.9%) and e-cigarette users (7.1%) vs non-smokers (7.6%); p=0.023. The need for previous surgical resection was higher in cigarette smokers (44.2%) and e-cigarette users (35.7%) vs non-smokers (26.8%); p=0.035.Results
Compared to the general population the proportion of current cigarette smokers (14.9% vs 17.2%) and e-cigarette users was similar in our cohort (4.26% vs 4%).Conclusion
IBD patients show similar smoking behaviour as the general population with 4% using e-cigarettes. The detrimental effect of smoking remains evident in out cohort. IBD patients use e-cigarettes as replacement for cigarettes or as an intermediate step for smoking cessation with no de-novo e-cigarette use in our cohort. Some health authority propose that e-cigarettes are less harmful to health than cigarettes. There are however little data on the effect in IBD. Large scale, prospective studies examining the effects of e-cigarette use are required.