P550 Patients’ perceptions about thiopurines are associated with early discontinuation in patients with inflammatory bowel diseases
M. Broekman*1, M. Coenen2, O. Klungel3, C. van Marrewijk2, G. Wanten1, L. Derijks4, S. Vermeulen2, 5, D. Wong6, A. Verbeek5, P. Hooymans6, H. Scheffer2, H.-J. Guchelaar7, M. Bouvy3, 8, D. de Jong1
1Radboud University Medical Centre, Department of Gastroenterology, Nijmegen, Netherlands, 2Radboud University Medical Centre, Department of Human Genetics, Nijmegen, Netherlands, 3Utrecht University, Departement of Pharmacoepidemiology and Clinical Pharmacotherapy, Utrecht, Netherlands, 4Maxima Medical Centre Loc. Veldhoven, Department of Gastroenterology and Hepatology, Veldhoven, Netherlands, 5Radboud University Medical Centre, Radboud Institute for Health Sciences, Nijmegen, Netherlands, 6Zuyderland Medical Centre, Department of Clinical Pharmacy, Pharmacology and Toxicology, Sittard, Netherlands, 7Leiden University Medical Centre, Department of Clinical Pharmacy and Toxicology, Leiden, Netherlands, 8SIR institute for Pharmacy Practice and Policy, Leiden, Netherlands
Patients’ beliefs about medicine are important predictors of drug adherence. These may either reflect patients’ beliefs on the necessity of treatment or concerns regarding potential drawbacks of treatment, such as side effects. Up to 40% of patients with inflammatory bowel disease (IBD) discontinues thiopurine treatment within the first year. We explored to which extent believes concerning thiopurines are associated with early treatment discontinuation of thiopurines.
Patients enrolled in the TOPIC trial (‘Thiopurine response Optimization by Pharmacogenetic testing in IBD clinics’) were asked to complete the Beliefs about Medicine Questionnaire (BMQ) after 4 weeks of thiopurine initiation. This validated questionnaire measures perceptions about ‘necessity’ (5 questions) and ‘concerns’ (6 questions) of thiopurine treatment. Items are rated on a 5-point Likert scale, and the sum of answers on each individual scale is converted into a score between 5 and 25. A higher score indicates either more necessity or more concerns. Based on a combined necessity and concerns score patients can be categorised in 4 believer groups towards thiopurine treatment; accepting (low concerns, high necessity), ambivalent (high concerns, high necessity), indifferent (low concerns, low necessity), and sceptical (high concerns, low necessity). The relation between discontinuation rates and believer groups was compared using Chi-squared test.
In the TOPIC trial, 767 patients started thiopurine treatment of whom 576 (74%) patients completed the BMQ. The discontinuation rate in the first 5 months was 34% amongst the respondents. Nonrespondents of the BMQ were younger (38 vs 42 years), had a shorter disease duration (4.2 vs 5.8 years), and more often discontinued treatment (52% vs 33%), p < 0.01 for all. Of the nonrespondents, 12% discontinued treatment already before week 4. The patients who completed the BMQ had a mean score of 17.1 for the necessity of treatment and 15.3 for the concerns. Based on these scores, patients were classified as accepting (34%), indifferent (17%), ambivalent (34%), and sceptical group (15%) towards thiopurine treatment. Concomitant discontinuation rates per believer group were, 22%, 35%, 37%, and 54%, respectively. Taking patients in the accepting group as reference, patients with an indifferent (p = 0.02), an ambivalent (p < 0.01), or sceptical believe (p < 0.01) towards thiopurines more frequently discontinued thiopurine therapy.
Extra attention towards IBD patients with high concerns or low necessity regarding thiopurine treatment might prevent them from premature discontinuation.