Background: We evaluated adherence to adalimumab therapy in Crohn's disease (CD).
Methods: This was an observational multicenter study conducted in four French university hospitals between April 4, 2008 and January 1, 2010. Patients were systematically asked, at each clinical visit, whether or not they delayed or missed an injection of adalimumab over the past 3 months. Patients were also asked about the reasons for their nonadherence.
Results: Of the 108 patients analyzed, 33 (30.6%) delayed the administration of at least one injection and 16 (14.8%) missed at least one injection over the past 3 months. The main reasons for overall nonadherence were: forgetfulness (24.6%), infection (24.6%), and travel (20%). Other reasons for nonadherence were intentional nonadherence (10.8%), pharmaceutical supply issues (9.2%), side effects (7.7%), pregnancy (1.5%), and CD-related hospitalization (1.5%). Adalimumab regimen of 40 mg every other week was a positive predictor for injection delays (P = 0.02, odds ratio [OR] = 3.76, 95% confidence interval [CI], 1.28-11.05), whereas having at least one relapse in the past 12 months was associated with fewer delays (P = 0.02, OR = 0.37, 95% CI, 0.15-0.87). [correction made here after initial online publication]. Disease duration over 90 months negatively predicted failure to inject adalimumab (P = 0.009, OR = 0.17, 95% CI, 0.05-0.64).
Conclusions: The overall nonadherence rate for adalimumab use was 45.4%. Most of the reasons for nonadherent behaviors could be avoided. An adalimumab regimen of 40 mg every other week was negatively related to adalimumab adherence; both the occurrence of at least one relapse in the past 12 months and disease duration over 90 months were positively related to adherence.