Adherence With Infliximab Therapy Decreases Hospitalization Rate And Inpatient Costs In Patients With Crohn'S Disease

Purpose: To assess the impact of adherence with infliximab (IFX) treatment in Crohn's disease (CD), during the first year of treatment, on CD-related hospitalization rate, inpatient costs, and hospital lengths of stay (HLOS). Methods: A retrospective claims analysis using the IMS LifeLinkTM Health Plan Claims Database between 09/01/2004 and 06/30/2009 was conducted. The index date was defined as the first claim for an IFX infusion between 9/1/2005 and 6/30/2008. Continuous enrollment for 12 months prior and 12 months after the index date was required. Patients were required to have ≥2 claims with an ICD-9 diagnosis code for CD (555.xx) pre-index, be ≥18 years at index, and have a minimum of 4 IFX infusions with a gap no greater than 12 weeks between each infusion. Patients with selected other inflammatory diseases during the pre-index period were excluded. Therapeutic adherence level was determined for the 12 months post-index by assessing the number of IFX infusions. Patients with 7-9 IFX infusions were considered adherent. Patients with 4-6 IFX infusions were considered non-adherent. CD-related hospitalization rate, inpatient costs, and HLOS (days) were compared between adherent and non-adherent patients. Statistical tests were run on hospitalization rate, median inpatient costs, and median HLOS. Results: A total of 638 patients were included in the analyses; mean (SD) age for both groups=43 (15) years; 58% female in the adherent group/53% female in the non-adherent group; mean (SD) 8 (0.7) IFX infusions in the adherent group/mean (SD) 5 (0.8) IFX infusions in the non-adherent group. A smaller proportion of adherent patients (n=466; 73%) required CD-related hospitalization (8.2% vs. 12.2%; p=0.117) compared to non-adherent patients (n=172; 27%). For patients requiring hospitalization, those with adherence incurred significantly lower mean/median inpatient costs ($13,427/$9,352 vs. $37,783/$28,864; p=0.001) and had shorter mean /median HLOS (5.92/5 vs. 12.76/8 days; p=0.015) than those with non-adherence. Adherence was significantly associated with lower inpatient costs after controlling for baseline characteristics in a multivariate model (p=0.0002). Conclusion: Adherence with IFX therapy during the first year of treatment was associated with fewer CD-related hospitalizations, lower inpatient costs, and shorter HLOS among patients with CD. Physicians should monitor their patients with CD to ensure appropriate IFX treatment paradigms are followed. Disclosure: Chureen Carter-Employee-Centocor Ortho Biotech Services, LLC Heidi C Waters-Employee-Centocor Ortho Biotech Services, LLC Daniel B Smith-Consultant-Centocor Ortho Biotech Services, LLC. This research was supported by an industry grant from Centocor Ortho Biotech Services, LLC.Table: [1099] Results by infliximab adherence level