Exploratory Analysis of Biologicals in the Drug Treatment of Patients with Crohn's Disease using Administrative Claims Data

Background: Crohn's disease (CD) is a chronic relapsing inflammatory condition of the gastrointestinal tract. It is of public health relevance because of a high morbidity as well as psychosocial burden and the patients’ need for a life-long intermittent medical treatment. New treatment options include biologicals (e.g. infliximab), which have a significant impact on CD management. Aim: The aim of this study was to describe the types and proportions of medications dispensed to persons with CD as well as treatment patterns of CD patients receiving biologicals in order to reflect their drug treatment situation. Further, this study aimed to describe the rate of complications and the extent of CD-related health care utilization of CD patients receiving different treatment intensities. Methods: Administrative claims data of two statutory health insurances with approximately 500.000 insurees were used to analyze the drugs dispensed to CD patients in annual cross-sectional designs (2004-2007). For 2007, the proportion of persons with complications and their health care utilization were assessed descriptively among CD patients receiving different treatment intensities. The description of treatment patterns of incident infliximab users was based on a longitudinal user cohort (2006-2007). Results: In 2007, 855 CD patients were identified. Of these, 528 (61.8 %) had any dispensation of CD drugs in this year (total: 3.791 dispensations). Aminosalicylic acids accounted for 32.0 % of these dispensations, followed by immunosuppressants (28.4 %), systemic corticosteroids (20.5 %), budesonide (13.9 %), topical medication (3.1 %) and biologicals (2.1 %). Overall, 39.3 % of the 855 CD patients received aminosalicylic acids at least once in 2007, 26.7 % had at least one dispensation of systemic corticosteroids, 19.3 % of immunosuppressants, 15.4 % of budesonide, 4.6 % of topical medication and 1.9 % of biologicals. Among CD patients with immunosuppressants or biologicals as the most potent drugs in 2007, a higher proportion had fistulas and operations compared to patients with less potent drugs. The CD-related health care utilization (hospitalizations, duration of hospital stays, ambulatory physician contacts) was also higher. Seven CD patients started infliximab in 2006 or 2007. The majority (5) had received other CD drugs in the 365 days before onset of infliximab therapy. Infliximab was applied as monotherapy in one person, in combination with azathioprine in four patients. Mesalazine enemas as well as prednisolone were also concomitantly used. The time intervals between consecutive applications showed a wide range and no clear infliximab application scheme was found. Conclusion: Aminosalicylic acids, systemic corticosteroids and immunosuppressants were important components in CD treatment, whereas biologicals were rarely dispensed. Patients with biologicals or immunosuppressants had more complications and showed a higher rate of health care utilization. Infliximab was mostly dispensed following the step-up approach and seemed to be applied on-demand