Switching to a Second Thiopurine in Adult and Elderly Patients With Inflammatory Bowel Disease: A Nationwide Study From the ENEIDA Registry
Authors: Calafat Margalida , Mañosa Míriam , Mesonero Francisco , Guardiola Jordi , Mínguez Miguel , Nos Pilar , Vera Isabel , Taxonera Carlos , Iglesias Eva , Ricart Elena , Gisbert Javier P , Calvet Xavier , García-López Santiago , Monfort David , Pérez Calle José Lázaro , Riestra Sabino , Gomollón Fernando , Garcia-Planella Esther , Bermejo Fernando , Hernández Vicent , Martín-Arranz María Dolores , Gutiérrez Ana , Torres Paola , Cañete Fiorella , Domènech Eugeni ,   ENEIDA registry of GETECCU, Águeda Abad , Guillermo Alcaín , Pedro Almela , Federico Argüelles H , Manuel Barreiro-de-Acosta C H , Fernando Bermejo , Luis Bujanda , David Busquets H , Xavier Calvet , Fiorella Cañete , Mara Charro H , Marta Cimavilla , Eugeni Domènech , Van Domselaar Manuel , Santiago García-López , Esther Garcia-Planella , Mariana-Fe García Sepulcre , Fernando Gomollón , Jordi Guardiola , Ana Gutiérrez , Vicent Hernández , José M Huguet , Eva Iglesias , Sam Khorrami , Jesús Legido , Jordina Llaó , Alfredo J Lucendo Villarín , Rosa Eva Madrigal , Míriam Mañosa , Lucía Márquez , María Dolores Martín- Arranz , Pilar Martínez Montiel , Olga Merino , Francisco Mesonero , Miguel Mínguez , David Monfort , Maria Mora , Carmen Muñoz , Orlando García-Bosch , Pilar Nos , José Lázaro Pérez Calle , Javier P Gisbert , Laura Ramos , Elena Ricart , Joan Riera , Sabino Riestra , Montserrat Rivero , Antonio Rodríguez , Cristina Rodríguez Gutiérrez , Ainhoa Rodríguez-Pescador H , Patricia Romero , Óscar Roncero , Eva Sesé H , Paola Torres , Milagros Vela , Benito Velayos , Isabel Vera , Cristina Verdejo , Yamile Zabana 
Published: March 2020

Abstract

Background and Aims
Although commonly used in inflammatory bowel disease [IBD], thiopurines frequently cause intolerance, and switching to a second thiopurine has only been reported in some small series. Ours aims in this study were to evaluate the safety of switching to a second thiopurine in a large cohort, and to assess the impact of age on tolerance.

Methods
Adult IBD patients from the ENEIDA registry, who were switched to a second thiopurine due to adverse events [excluding malignancies and infections], were identified. At the beginning of thiopurine treatment, patients were divided by age into two groups: 18–50 and over 60 years of age. The rate and concordance of adverse events between the first and second thiopurines, treatment intolerance, and persistence with the second thiopurine were evaluated.

Results
A total of 1278 patients [13% over 60 years of age] were switched to a second thiopurine. At 12 months, the cumulative probability of switch intolerance was 43%, and persistence with treatment was 49%. Independent risk factors of switch intolerance were age over 60 years (odds ratio [OR] 1.49; 95% confidence interval [CI] 1.07–2.07; p = 0.017) , previous gastrointestinal toxicity [OR 1.4; 95% CI 1.11–1.78; p = 0.005], previous acute pancreatitis [OR 6.78; 95% CI 2.55–18.05; p &lt;0.001], and exposure to the first thiopurine &lt;6 months [OR 1.59; 95% CI 1.14–2.23; p = 0.007].

Conclusions
In a large series in clinical practice, switching to a second thiopurine proved to be a valid strategy. Tight monitoring of elderly IBD patients switching to a second thiopurine because of adverse events is recommended.