Objective: The aim of this study was to identify determinants of nonadherence to medication in outpatients with established inflammatory bowel disease (IBD).
Methods: Ten gastroenterologists and 153 of their IBD patients participated in this prospective study. Demographic, clinical, and psychosocial characteristics, as well as patient-physician discordance, were assessed at an office visit. Nonadherence to medication was assessed 2 wk later. Separate generalized estimating equations were used to identify determinants of nonadherence.
Results: Physicians averaged 47.9 yr in age (range 30.1-57.5 yr), and 90% were male. Patients averaged 37.0 yr (SD = 15.1), and 87 (56.9%) were female. In all, 63 patients (41.2%) were nonadherent to medication; of these, 51 (81.0%) indicated unintentional nonadherence, 23 (36.5%) intentional nonadherence, and 11 (17.5%) both. Overall nonadherence was predicted by disease activity (OR = 0.55, p = 0.0022), new patient status (OR = 2.14, p = 0.0394), disease duration (OR = 0.50, p = 0.0001), and scheduling a follow-up appointment (OR = 0.30, p = 0.0059), whereas higher discordance on well-being was predictive only in psychologically nondistressed patients (p = 0.0026 for interaction). Unintentional nonadherence was predicted by age (OR = 0.97, p = 0.0072), new patient status (OR = 2.80, p = 0239), and higher discordance on well-being in psychologically nondistressed patients (p = 0.0504). Intentional nonadherence was predicted by disease duration (OR = 0.55, p = 0032), scheduling a follow-up appointment (OR = 0.12, p = 0.0001), certainty that medication would be helpful (OR = 0.99, p = 0.0409), and total patient-physician discordance (OR = 1.59, p =.0120).
Conclusions: These findings suggest that the therapeutic relationship, as well as individual clinical and psychosocial characteristics, influence adherence to medication.