Which factors predict SpA symptoms in IBD patients?

Many patients with inflammatory bowel disease (IBD) test positive for symptoms of spondyloarthritis (SpA), suggesting a high burden of undiagnosed illness, reports a study.

Researchers administered two validated screening questionnaires for the detection of SpA in IBD (DETAIL = DETection of Arthritis in Inflammatory boweL diseases; IBIS-Q = IBD Identification of Spondyloarthritis Questionnaire) to patients with IBD without a prior diagnosis of SpA in six US academic medical centres. They also recorded the demographic data, IBD characteristics, and medication history of these patients.

A total of 588 patients (220 ulcerative colitis, 349 Crohn’s diseases, 19 unclassified), with a median age of 40 years and median disease duration of 12 years, completed the screening questionnaires. The number of positive screens was 130 (22 percent) for DETAIL, 196 (33 percent) for IBIS-Q, and 204 (35 percent) for either questionnaire.

Univariate analysis revealed the association of age, female sex, history of smoking, prior bowel surgery, and history of any biologic or targeted small molecule exposure with a positive screen.

In multivariate analysis, the following factors remained independently associated with positive screens: female sex (odds ratio [OR], 2.03, 95 percent confidence interval [CI], 1.41–2.93), older age (OR, 1.02, 95 percent CI, 1.01–1.04), history of smoking (OR, 1.67, 95 percent CI, 1.04–2.69), and history of any biologic or targeted small molecule exposure (OR, 2.27, 95 percent CI, 1.34–3.84).

Furthermore, a higher number of exposures to biologics correlated with a greater likelihood of positive screens, with the highest odds seen with three or more exposures (OR, 3.25, 95 percent CI, 1.75–6.03).

"Factors associated with SpA symptoms include older age, female sex, and more severe disease (based on increased number of advanced therapies or prior surgery), whereas IBD phenotype does not independently increase the risk of a positive SpA screen,” the researchers said.

“Further studies are needed to confirm these findings and better characterize SpA in IBD,” they added.