Persistence to oral 5-aminosalicylate therapy for inflammatory bowel disease in Australia

Abstract

Aminosalicylate (5-ASA) is effective treatment for inflammatory bowel diseases (IBDs) but requires continuous maintenance therapy. This study determines persistence of 5-ASA in IBD using national population-based data for Australia from 2002 to 2011 with follow up for 36 months. Non-persistence was defined as failing to fill a prescription for 3 months. Of 12,592 patients those initiated on non-sulphasalazine 5-ASA (2917) had significantly higher persistence (P < 0.001) than those on sulphasalazine (9675). Persistence for sulphasalazine and non-sulphasalazine 5-ASA initiation was 22.3% and 28.5% at 12-months, and 11.9% and 16.2% at 24-months. Sulphasalazine poor persistence continued despite intra-class switch to another 5-ASA. Patients receiving immunomodulator co-therapy had higher persistence (P < 0.001). National population-based data identified persistence to 5-ASA to be low but significantly lower when sulphasalazine is the initial drug. Physicians should stress the importance of long-term 5-ASA therapy as overall drug efficacy especially the 5-ASA chemo-prophylactic benefits may be reduced by non-persistence.

Keywords::

• adherence
• inflammatory bowel disease
• persistence
• sulphasalazine

Ethics approval

The study was approved by the Medicare Australia ethics committee.

Authors' contribution

C Selinger performed data analysis, interpreted the data and wrote the draft manuscript. A Kemp performed data analysis contributed to data interpretation and critically reviewed the manuscript. RW Leong interpreted the data and critically reviewed the manuscript.

Financial & competing interests disclosure

The study was funded by an unrestricted research grant from Ferring Pharmaceuticals Australia. R Leong has acted as a speaker and on the advisory board for Ferring Pharmaceuticals and has received grants from Ferring, Shire and Nycomed. C Selinger has received grants from Ferring, Shire, Warner Chilcott and Nycomed. A Kemp is an employee of Medilinx Australia. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Aminosalicylate (5-ASA) long-term therapy is required to derive the intended benefits of flare prevention and chemoprophylaxis.

• Persistence to 5-ASA is very low at 36 months of follow-up.

• Patients initiated on nonsulfasalazine 5-ASA have better persistence than those on sulfasalazine.

• Immunomodulator cotherapy is associated with better persistence.

• Physicians need to be aware of low persistence to proactively address the issue with their patients.