University of Florida Shands Hospital Gainesville, FL
Introduction: Smoking is associated with a reduced ability to induce short-term clinical response and remission in Crohn’s patients using biologics. Few studies have investigated the impact of smoking on therapeutic response of Inflammatory Bowel Disease (IBD) treatments using biologics only, but none have considered impact of smoking using biologics, immunomodulators or both. The aim of this study is to assess the utility of C-Reactive Protein (CRP)/albumin ratio in measuring treatment response in all IBD patients in relation to smoking status.
Methods: Retrospective analysis was performed on adults ( >18 years old) with an ICD-9/10 code diagnosis of Crohn’s or UC disease during their index hospitalization for IBD flare to a tertiary care center between January 1st 2013 to June 1st 2017. Non-consented patients were excluded. Treatment during index hospitalization was documented as either using biologics, immunomodulators or both. Inflammation status to measure treatment response was assessed using CRP /albumin ratio. Smoking status was defined as ever or never smoker.
Results: Out of 1101 IBD patients, 418 patients had a documented smoking status and a calculable CRP/Albumin ratio; 168 (40.2%) were ever smokers and 250 (59.8%) were never smokers. Among never-smoker IBD, Crohn’s and UC patients, those who received biologics, immunomodulators or both had a lower mean CRP/Albumin ratio than those who did not (Table 1). Never-smoker IBD and UC patients who used biologics, had statistically significant lower mean CRP/Albumin ratio than those who did not, (p=0.010 and p=0.006, respectively). Among majority of ever-smoker IBD, Crohn’s and UC patients, those who received biologics, immunomodulators or both had a higher mean CRP/Albumin ratio than those who did not (Table 1). Ever-smoker IBD and UC patients who used immunomodulators and biologics, had statistically significant higher mean CRP/Albumin ratio than those who did not, (p=0.026 and p=0.041, respectively).
Discussion: Smoking is associated with worsening therapeutic response to treatments in all IBD, Crohn’s and UC patients, with an amplified effect when both immunomodulators and biologics are used. On the other hand, regardless of type of therapy received, never-smokers have an improved response to treatment in all IBD, Crohn’s and UC patients. Further investigation is warranted to understand the interaction of smoking with IBD treatment at the biochemical level in the light of disease progression.
