Systematic review and meta-analysis: assessment of factors affecting disability in inflammatory bowel disease and the reliability of the inflammatory bowel disease disability index.

Background The Inflammatory Bowel Disease Disability Index ( IBD- DI) has recently been developed for patients with Crohn's disease ( CD) and ulcerative colitis ( UC). Aim To assess the severity of disability and associated factors using the IBD- DI, and review the validity of the IBD- DI as a tool. Method Systematic review of cross-sectional studies. Patients included had UC or CD and were classified as active, in remission, or needing surgery, biological and/or steroid treatment. We included studies assessing disability using the IBD- DI and that were captured by electronic and manual searches (January 2017). The possibility of bias was evaluated with the Newcastle-Ottawa Scale. Results Nine studies were included with 3167 patients. Comparatively, patients with active disease had higher disability rates than those in remission ( SMD [ CI95] = 1.49[1.11, 1.88], I ² = 94% , P<.01), while patients on biological treatment had lower disability rates than those receiving corticosteroid treatment ( SMD [ CI95] = −0.22[−0.36, −0.08], I ² = 0%, P<.01). Disease activity and unemployment were found to be associated factors. The IBD- DI scored 'good' for internal consistency, 'fair' to 'excellent' for intra-rater reliability and 'excellent' for inter-rater reliability. Construct validity was 'moderately strong' to 'very strong' and structural validity was found to be mainly unidimensional. The IBD- DI had excellent responsiveness, while its interpretability was only useful on a group level. Conclusions This systematic review and meta-analysis found a significant association between disease activity, treatment received and disability; although significant heterogeneity was found. The IBD- DI is reliable and valid, but further studies are needed to measure its interpretability. [ABSTRACT FROM AUTHOR]