Background: There are few studies on the short-term efficacy of adalimumab treatment for patients with Crohn's disease (CD). Here, we report the results of the Short-term Outcomes of Adalimumab for Patients with Crohn's disease and Associated Prognostic Factors: A Multicentre Retrospective Cohort Study in Japan (SAPPORO).
Methods: The SAPPORO study was conducted at 9 institutions. Data were retrospectively collected from CD patients who received adalimumab from October 2010 to September 2015. Patients had to have a Harvey–Bradshaw index (HBI) of ≥5 points at the first adalimumab administration. The HBI score and C-reactive protein (CRP) level were investigated at baseline and at 2, 4, 8 and 12 weeks following adalimumab administration. Remission was defined as an HBI score of ≤4. Rate of remission and remission with a normal CRP level were assessed at 2, 4, 8 and 12 weeks. The prognostic factors associated with the rate of remission with a normal CRP level at 4 and 12 weeks were evaluated using univariate and multivariate logistic regression analysis.
Results: Of the 160 patients included in this study (median age, 29.3 years), 56 were female. The HBI scores significantly decreased sequentially from baseline to 2, 4, 8 and 12 weeks as follows: 8.0, 4.0, 3.3, 3.4 and 3.5, respectively. The CRP levels also significantly decreased sequentially as follows: 2.43, 0.71, 0.95, 0.91 and 1.37 mg/dL, respectively. Rates of remission at 2, 4, 8 and 12 weeks were 61%, 73%, 71% and 69%, respectively, while rates of remission with a normal CRP level were 36%, 51%, 49% and 49%, respectively. In the univariate analyses, previous infliximab (IFX) use, penetrating disease, a disease duration of ≥4.3 years, previous bowel resection, being ≥29.3 years old and CRP levels of ≥1.55 mg/dL were significant prognostic factors for a lower rate of remission with a normal CRP level at 4 and 12 weeks. In addition, a body mass index (BMI) of ≥18.5 and HBI of ≥7 were significant prognostic factors for a lower remission rate with a normal CRP level at 12 weeks. In the multivariate logistic regression analysis, previous IFX use and CRP levels of ≥1.55 mg/dL were identified as independent predictors of a lower rate of remission with a normal CRP level at 4 and 12 weeks. Furthermore, a BMI of ≥18.5 was identified as an independent predictor for a lower rate of remission with a normal CRP level at 12 weeks.
Conclusions: The short-term efficacy of adalimumab treatment for CD patients was demonstrated by the second week. Approximately 50% of the patients achieved remission with a normal CRP level at 4 weeks. Previous IFX use, higher CRP levels and a higher BMI appear to be associated with poor short-term outcomes of adalimumab treatment.