Frequency and trends of disease-modifying antirheumatic drug (DMARD) use in Germany

The aim of this study was to analyze the population-based frequency of classic (c-) and biologic (b-) disease-modifying antirheumatic drug (DMARD) use over time, selected underlying indications and the specialty of the prescribing physicians in Germany. Based on the claims data of the German Pharmacoepidemiological Research Database (GePaRD), yearly cross-sectional studies were conducted from 2004 to 2011. The prevalence of DMARD use was calculated as the number of persons with at least one dispensation per 1000 persons stratified by sex and age. In 2011, we also obtained the proportion of c-and b-DMARDs users with diagnoses of selected indications and the proportion of dispensations by specialty of the physician. Between 2004 and 2011, the annual prevalence of b-DMARD and c-DMARD use increased from 0.35 parts per thousand to 1.54 parts per thousand and from 6.53 parts per thousand to 8.93 parts per thousand, respectively. In 2011, the study population comprised 12.8 million insurants with a mean age of 44.0 years. During this year, among c-DMARDs, methotrexate was prescribed most frequently (4.76 parts per thousand), followed by azathioprine (1.72 parts per thousand) and sulfasalazine (1.20 parts per thousand). For b-DMARDs, adalimumab (0.57 parts per thousand), etanercept (0.46 parts per thousand), and rituximab (0.23 parts per thousand) were most frequently used. Notably, b-DMARD users more often had a diagnosis of ankylosing spondylitis and psoriasis compared to c-DMARD-users (20.7% vs. 2.9% and 20.0% vs. 11.4%, respectively) and b-DMARDs were more frequently prescribed by rheumatologists and other specialists. Our population-based study highlights the increasing use of c-and b-DMARDs in Germany. Compared to c-DMARDs, b-DMARDs were commonly used for indications besides rheumatoid arthritis. Future research should therefore also focus on their prescription patterns and safety aspects in indications other than RA.