Symptoms compatible with Rome IV functional bowel disorder in patients with ankylosing spondylitis.

Objectives: To determine the frequency of symptoms meeting Rome IV functional bowel disorder (FBD) in patients with ankylosing spondylitis (AS), investigate factors associated with FBD symptoms, and assess whether having FBD symptoms might influence AS disease activity. Methods: In this cross-sectional study, we enrolled 153 AS patients without known colonic ulcers and 56 sex- and age-matched controls to evaluate FBD (or its subtypes) symptoms. Disease characteristics were also evaluated in the AS group. Results: Sixty (39.2%) of 153 AS patients had FBD symptoms, which were more prevalent than controls (23.2%). Besides, symptoms compatible with irritable bowel syndrome (IBS) and chronic diarrhoea were detected in 18 and 43 AS patients, respectively. For the AS group, multivariable logistic regression analyses showed that symptoms of FBD, IBS, and chronic diarrhoea were negatively associated with using non-steroidal antiinflammatory drugs and positively associated with comorbid fibromyalgia, respectively. In exploration about the effects of FBD (or its subtypes) symptoms on AS disease activity by multivariable linear regression analyses, FBD symptoms and chronic diarrhoea had universal positive associations with assessments of AS disease characteristics, respectively. Conclusions: Patients with AS had frequent symptoms compatible with FBD, IBS, and chronic diarrhoea, proportions of which were lower in those with non-steroidal anti-inflammatory drug use. The improvement of FBD symptoms and chronic diarrhoea might be conducive to the disease status of AS patients. [ABSTRACT FROM AUTHOR]