Introduction Although inflammatory bowel disease (IBD)-related knowledge empowers patients, it may engender anxiety and impair quality of life (QOL). We aimed to identify predictors of anxiety in IBD and the association with knowledge and disease-related QOL.

Methods Ambulatory IBD patients were recruited from two Australian tertiary hospital clinics and office-based gastroenterologists. Self-administered questionnaire data were collected on demographics and details of IBD, including Crohn's Colitis Association membership status. Disease-related knowledge was assessed using the validated Crohn's and Colitis Knowledge score (CCKnow) and disease related QOL using the short IBD questionnaire (SIBDQ). Anxiety (HADS-A) and depression (HADS-D) were assessed with the Hospital Anxiety and Depression Scores with significance defined as HADS>10 and probable disorder as HADS 8–10. Statistical analysis was performed using Student t test and ANOVA.

Results 258 patients (53.9% female, median age 47 years) were included. 50 patients (19.4%) had clinically significant anxiety and 58 (22.4%) had probable anxiety. Age, marital status, highest level of education, employment status, household income, diagnosis (Crohn's vs ulcerative colitis) and duration of disease were all unassociated with higher anxiety levels. Female patients (HADS-A 7.5 vs 6.0 [males], p=0.003), hospital outpatients (7.8 vs 6.3 [from office based doctors], p=0.014) and non-Caucasian patients (7.9 vs 6.4 [Caucasians], p=0.037) had significantly higher anxiety levels, while Crohn's Colitis Association members had marginally higher levels of anxiety (7.7 vs 6.5 [non-members], p=0.07). Disease related patient knowledge was higher in females (CCKnow 11.3 vs 8.4 [males], p<0.001), but was not influenced by diagnosis or ethnicity. Anxiety (HADS≥8) was associated with significantly better patient knowledge (CCKnow 10.8 vs 9.3, p=0.016) and increased depression (HADS-D 6.4 vs 3.1, p<0.001). Disease related quality of life was significantly lower in patients with anxiety (SIBDQ 44.8 vs 57.4, p<0.001).

Conclusion Better patient knowledge is associated with higher anxiety levels. Educating patients about their disease and associated risks of surgery, cancer, infertility, etc might trigger anxiety. On the other hand anxious patients might seek out disease related information and hence acquire better knowledge. Our results suggest that an educational intervention may not be suitable to reduce anxiety. Anxiety is common in IBD patients and is associated with depression and significantly impaired quality of life. It may develop as the consequence of diminished quality of life from active IBD, but anxiety itself may lead to impaired quality of life.

Competing interests None declared.