Socioeconomic equality in initiation of biologic treatment in Danish patients with inflammatory bowel disease.

Background: Low socioeconomic status is associated with disadvantages in health outcomes and delivery of medical care in patients with Inflammatory Bowel Disease (IBD). Inequality in the utilisation of biologic treatment is largely unexplored.

Aim: To explore the potential association of socioeconomic status and time to first biologic treatment in a population-based IBD cohort.

Methods: All 37,380 IBD incidences between 2000 and 2017 from the Danish National Patient Register were identified and linked to socioeconomic information including educational level, income and occupational status at diagnosis. Hazard ratios for receiving biologic treatment among socioeconomic groups were estimated using Cox proportional hazard regression.

Results: No difference in time between diagnosis and biologic treatment initiation was found comparing patients with upper secondary, vocational, or academic education to those with lower secondary education in patients with IBD. Patients with Crohn's disease in the two highest income quartiles received biologic treatment earlier (HR 1.16; 95% CI: 1.04; 1.30 & HR 1.15; 95% CI: 1.03; 1.30). An elevated treatment rate was found for persons with "other" occupational status (unspecified source of income) compared to employed persons in patients with ulcerative colitis (HR 1.36; 95% CI: 1.11; 1.66), but not in patients with Crohn's disease.

Conclusion: This study revealed equal initiation of biologic treatment among patients with IBD across different educational background, income and occupational status. However, results are limited to a setting with free universal healthcare coverage and treatment needs should be considered and addressed in future research.