Background: Adalimumab (ADA) is an effective treatment for Crohn's disease (CD). In rheumatology, sex differences concerning the response to ADA therapy have been described. However, such differences have not yet been reported for patients with CD. As such, the aim of this study was to compare ADA treatment outcomes in male and female patients with CD.
Methods: A clinical cohort was formed of consecutive patients with CD starting ADA in a single tertiary center between March 2006 and February 2011. The cohort was followed up to August 2015. Clinical outcomes were primary nonresponse, secondary nonresponse, and drug survival (ongoing ADA use). Reasons for stopping ADA were recorded. Kaplan-Meier analysis and Cox regression were used to assess drug survival.
Results: The cohort consisted of 107 female and 81 male patients. Median follow-up was 6.0 years (range 0.3-9.2). Drug survival was higher in male than female patients (48.1% versus 30.8%, P = 0.016). Side effects were reported more often by female patients (81.3% versus 64.2%, P = 0.008), and female patients ceased ADA more often due to side effects (35.4% versus 18.4%, P = 0.017). In survival analysis, female sex was associated with higher cessation rates (P = 0.006). Cox regression also identified female sex (P = 0.020), along with higher baseline CD Activity Index (P = 0.003), as predictors of ADA cessation.
Conclusions: Female sex is negatively associated with ADA drug survival. Female patients report more side effects and cease ADA because of side effects more often. A more personalized and sex-specific approach seems warranted to increase drug survival in female patients.