Abstract: | SummaryThis study estimated the incidence of rheumatoid arthritis (RA) in a US population comprising adults from the MarketScan Research Database®*. The incidence population included subjects with no RA-related medical claims or treatment history during 2001–2002. Among the incidence population, patients with RA in 2003 made up the newly diagnosed RA population and patients with RA for more than 3 years comprised the longstanding RA population.The age- and sex-adjusted RA incidence based on the 2002 US population was 0.08% (0.06% in males; 0.11% in females); the age- and sex-adjusted prevalence was 0.73% (0.43% in males; 0.98% in females). The prevalence-to-incidence ratio was 9.1 (7.2 in males; 8.9 in females). Treatment with non-steroidal anti-inflammatory drugs, disease-modifying antirheumatic drugs and biologicals, respectively, was documented in 36.7, 17.7 and 2.5% of newly diagnosed patients within 12 months after initial diagnosis and in 68.2, 87.3 and 34.4%, respectively, of patients with longstanding RA.Management of existing RA cases remains a challenge, with only a small proportion of new cases receiving standard treatment. |