biostudies-literatureThomsen SBAage og Johanne Louis-Hansens FondNNF Center for Basic Metabolic Research68-76https://www.ebi.ac.uk/biostudies/studies/S-EPMC7006001biostudies-literatureUnknown8(1)<h4>Background</h4>Thiopurine and allopurinol in combination are associated with clinical remission in inflammatory bowel diseases but their influence on subsequent outcomes is unclear. We compared outcomes during exposure to both thiopurines and allopurinol versus thiopurines alone.<h4>Methods</h4>We established a nationwide cohort of patients with inflammatory bowel diseases exposed to thiopurines ± allopurinol during 1999-2014, using registry data. Patients were followed until hospitalization, surgery, anti-TNFα, or death (as a primary composite outcome). We used Poisson regression analyses to calculate incidence rate ratios overall and stratified by calendar period (assuming the combined exposure was unintended before 2009).<h4>Results</h4>A total of 10,367 patients with inflammatory bUnited European gastroenterology journalOutcome of concomitant treatment with thiopurines and allopurinol in patients with inflammatory bowel disease: A nationwide Danish cohort study.PMC7006001Pedersen Group18-2B-3487Hansen STheede KJess TAllin KHKiszka-Kanowitz MNielsen AMThomsen SBGluud LLBurisch JJensen CBfalseOutcome of concomitant treatment with thiopurines and allopurinol in patients with inflammatory bowel disease: A nationwide Danish cohort study.<h4>Background</h4>Thiopurine and allopurinol in combination are associated with clinical remission in inflammatory bowel diseases but their influence on subsequent outcomes is unclear. We compared outcomes during exposure to both thiopurines and allopurinol versus thiopurines alone.<h4>Methods</h4>We established a nationwide cohort of patients with inflammatory bowel diseases exposed to thiopurines ± allopurinol during 1999-2014, using registry data. Patients were followed until hospitalization, surgery, anti-TNFα, or death (as a primary composite outcome). We used Poisson regression analyses to calculate incidence rate ratios overall and stratified by calendar period (assuming the combined exposure was unintended before 2009).<h4>Results</h4>A total of 10,367 patients with inflammatory b2020-01-01T00:00:00Z2020 Feb2025-04-22T00:19:41.707Z2021-02-20T19:21:21ZS-EPMC70060013221305910.1177/2050640619868387