Inflammatory bowel disease and asthma. Results from the RHINE study.

Background: Asthma and inflammatory bowel disease (IBD) are common inflammatory diseases. The aim of this study was to investigate the associations of IBD with asthma and respiratory symptoms.

Methods: This study is based on 13,499 participants from seven northern European countries that filled in a postal questionnaire on asthma, respiratory symptoms, IBD including ulcerative colitis and Crohn's disease and various lifestyle variables.