Inflammatory Bowel Disease and Pain Interference: A Conceptual Model for the Role of Insomnia, Fatigue, and Pain Catastrophizing

BACKGROUND: People with inflammatory bowel disease (IBD) commonly experience pain influenced by complex interactions among factors, including disease activity, sleep, psychopathology, and changes in pain processing pathways. Treatments for pain in IBD are limited, highlighting the need for research that explores modifiable factors linked to pain. The aim of this study was to investigate relationships among multiple patient factors and to construct a conceptual model for pain interference in IBD. METHODS: A cross-sectional survey of adults with IBD. Study domains included demographic, comorbidity, psychological, IBD, insomnia, fatigue, and pain features. Structural equation modeling (SEM) was used to examine relationships and interactions among active IBD, insomnia, fatigue, pain experiences (severity, catastrophizing, and interference), and additional patient factors (demographics and psychological). RESULTS: One hundred and seventy-four participants, aged 18–85 years, reported the presence of pain. Combining the questionnaire data using SEM resulted in a final model with an excellent fit (χ(2)(8) = 9.579, P = .297, χ(2)/N = 1.197, CFIN = 0.997, TLI = 0.987, RMSEA = 0.034). The presence of anxiety and depression was the additional patient factors to be retained in the path analysis. SEM results indicated that greater pain interference was directly influenced by greater fatigue, worse pain catastrophizing, and worse pain severity. Pain interference was indirectly impacted by IBD activity, worse insomnia, and the presence of depression and anxiety. CONCLUSIONS: The proposed conceptual model highlights the role of multiple potentially modifiable factors, including insomnia, pain catastrophizing, and fatigue, contributing to worse pain interference in people with IBD.