Personality, smoking and inflammatory bowel disease.

OBJECTIVE To assess whether psychological factors distinguished patients with Crohn's disease (CD) from those with ulcerative colitis (UC). DESIGN Survey of prevalent inflammatory bowel disease patients (n = 82) attending a gastroenterology clinic. METHODS Administration of three self-report rating scales, the Eysenck Personality Questionnaire, the General Health Questionnaire and the Hospital Anxiety and Depression scale. RESULTS CD patients were significantly more extroverted (P = 0.04) than UC patients, tended to have higher psychoticism scores (P = 0.06) but similar neuroticism scores. Extroversion and psychoticism scores were weakly associated with smoking status. In logistic regression models that adjusted for age, sex and smoking the associations with extroversion and psychoticism scores persisted but were no longer significant at the 5% level. In the final model the psychoticism score was more important than the extroversion score. CONCLUSION These results suggest that there are substantial personality differences between patients with CD and UC. Although some of the differences in this study were associated with smoking, adjusting for smoking reduced, but did not abolish, the associations with personality scores.