Use of biological disease modifying antirheumatic drugs in rheumatoid arthritis in Austria from 2008 to 2011 : A retrospective analysis of 72% of the population.

BACKGROUND: Rheumatoid arthritis (RA) is the most prevalent chronic inflammatory joint disease. On a national level in Austria, there are currently no data available on how often and which biological disease modifying antirheumatic drugs (bDMARDs) are prescribed in patients with RA. The aim of the present study was to explore prescription patterns of bDMARDs in RA in Austria with a focus on drug survival.

METHODS: A retrospective data analysis of bDMARD courses of individual patients with RA that were extracted from the databases of nine Austrian health insurance funds covering 6.1 million (72%) insured people in a 4-year observation period from January 2008 to December 2011. Only patients with first prescriptions of bDMARDs were included. All patients with diagnoses other than RA were excluded.

RESULTS: A total of 2906 first prescriptions of bDMARDs were included in the present analysis and 19.35% of RA patients were on bDMARDs in Austria taking into account a prevalence of RA of 0.5%. Tocilizumab showed the longest drug survival after 1 year (73.2%), followed by abatacept which had the longest drug survival after 2 (68.2%) and 3 years (65.2%). The most frequent second bDMARDs switched to were adalimumab (n = 109, 26%), tocilizumab (n = 83, 20%) and etanercept (n = 82, 20%) and 37% of biological DMARDs were prescribed as monotherapy (ranging from 33% with infliximab to 46% with tocilizumab).

CONCLUSIONS: Our analysis is based on the largest health care database available in Austria. Tocilizumab and abatacept showed the longest drug survival. Adalimumab, tocilizumab and etanercept were the most frequent DMARDs switched to. Of interest was the high number of bDMARD monotherapies.