Extended report Table 3 RA measures in the QUEST–RA study in Europe and other countries, in descending order of GDP GDP 2005 per capita (US$1000) DAS28 (0–9.1), mean SJC (0–28), median TJC (0–28), median HAQ Physician physical global function (0–10), (0–3), median median Pain VAS (0–10), median Patient global VAS (0–10), median PS-HAQ (0–3), mean ESR, median RF- Erosive positive, disease, % % Country Europe Ireland Denmark Sweden The Netherlands Finland UK France Germany Italy Spain Greece Hungary Estonia Poland Lithuania Latvia Serbia Kosovo Non-Europe USA Canada UAE Russia Turkey Brazil Argentina Total 48.7 47.9 39.6 38.9 37.3 37.3 35.0 33.9 30.5 26.1 25.6 10.9 10.3 8.0 7.5 7.0 3.5 3.5 41.9 35.2 32.4 5.3 5.0 4.8 4.7 4.1 3.4 3.8 3.1 3.3 4.0 3.7 4.4 4.5 3.5 3.4 5.1 4.7 5.3 5.5 5.2 5.9 6.0 3.3 4.1 4.3 5.0 4.2 4.2 5.3 4.2 3 1 2 1 1 1 1 3 2 1 0 5 4 6 3 4 6 6 2 2 3 5 0 3 9 2 4 2 2 0 1 4 2 4 4 1 1 7 6 9 12 8 18 16 1 4 3 6 2.5 2 10.5 4 1.6 1.3 1.4 0.7 0.9 1.8 2.5 3.0 3.0 1.2 1.1 3.3 3.0 4.3 4.1 4.9 4.6 4.7 1.9 1.8 2.6 3.4 2.0 1.5 4.7 2.4 0.75 0.63 0.88 0.75 0.63 0.88 0.88 0.75 1.00 0.88 0.25 1.38 1.13 1.38 1.38 1.38 1.63 1.63 0.63 1.00 0.63 1.13 0.88 0.63 1.00 0.88 3.4 2.6 3.3 2.5 2.8 4.1 3.9 5.0 4.9 3.1 2.3 5.2 4.3 5.0 5.2 5.1 5.1 5.1 3.2 4.6 3.7 3.5 4.2 3.2 5.0 4.1 2.9 2.8 3.3 2.7 2.8 3.6 3.6 4.9 5.0 3.6 2.0 5.1 4.8 4.8 5.3 5.7 5.3 5.0 2.6 4.0 2.8 4.5 4.6 3.5 4.7 4.2 0.61 0.53 0.56 0.54 0.46 0.69 0.90 0.81 0.97 0.88 0.77 1.08 0.95 0.97 1.01 0.93 1.38 1.47 0.47 0.69 0.69 1.21 0.94 0.71 1.13 0.82 18 14 19 15 13 19 16 20 28 17 23 26 24 31 29 26 28 45 14 21 24 24 30 28 30 22 80 73 82 69 75 81 75 61 71 73 52 93 68 70 78 85 71 81 71 83 75 75 68 80 90 74 60 64 60 44 56 69 76 78 38 60 71 93 86 62 79 97 80 99 36 45 47 60 56 63 68 63 DAS28, disease activity score in 28 joints; ESR, erythrocyte sedimentation rate; GDP, gross domestic product; HAQ, health assessment questionnaire; Physician global, physician global estimate of status; PS-HAQ, psychological HAQ; RA, rheumatoid arthritis; RF, rheumatoid factor; SJC, swollen joint count; TJC, tender joint count; UAE, United Arab Emirates; VAS, visual analogue scale. Brazil—percentages greater than 100 indicate the simultaneous use of two or more DMARD. Methotrexate covered 21–57% of disease duration and the use of biologic agents covered 0.2–14% (table 4). Differences in the DAS28 scores of patients who were taking or not taking methotrexate were small within ‘‘high GDP’’ countries (3.6 vs 3.8) and ‘‘low GDP’’ countries (5.1 vs 5.2) but large between ‘‘high GDP’’ versus ‘‘low GDP’’ countries (p,0.001; table 5). Similar patterns were seen for patients who were currently taking or not taking prednisone. Patients who were taking or not taking biological agents in ‘‘high GDP’’ countries had similar disease activity levels of 3.7, whereas in ‘‘low GDP’’ countries those who were taking biological agents had a statistically significantly lower mean DAS28 of 4.4 compared with patients who were not taking biological agents (DAS28 5.2; p,0.001). Linear regression models for GDP and disease activity The mean DAS28 varied among countries from 3.1 to 6.0 (table 2), and was associated significantly with GDP (r = 20.78, 95% CI 20.56 to 20.90, r2 = 61%); a stronger association (r = 20.85, 95% CI 20.63 to 20.94, r2 = 72%) was seen when only 18 European countries were included (fig 1; data from USA presented as a reference in the figure). Among European countries, an increase of GDP per 1000J translates to a decrease of DAS28 of 20.10 (95% CI 20.061 to 20.13). Ann Rheum Dis 2009;68:1666–1672. doi:10.1136/ard.2009.109983 DISCUSSION These data from the QUEST–RA database indicate that the burden of RA is substantially greater in ‘‘low GDP’’ than in ‘‘high GDP’’ countries, within and outside of Europe. These results are consistent with data concerning other chronic diseases and general health in different countries.7–9 17 The burden of chronic diseases, recognised as an important neglected global health issue,18 is greatest in low and middle income countries.19 Most chronic diseases occur at substantially higher frequency in individuals of low socioeconomic status, particu- larly before the age of 65 years.1–6 Poor outcomes of RA including mortality are associated with low socioeconomic status.5 20 Associations of low socioeconomic status and poor health, within and between countries, are regarded in most medical literature as based primarily on limited access to medical care and problems in the structure of clinical care,21–23 reflecting a ‘‘biomedical model’’, the dominant paradigm of 20th century medicine.23 24 However, in the present study, all patients had access to a rheumatologist, and 88–100% of patients had taken DMARD, including 69–98% who had taken methotrexate. Treatment-related variables were quite similar between ‘‘high GDP’’ and ‘‘low GDP’’ countries, including 97% of patients who had used DMARD, a delay of 9 months to the start of DMARD after first symptoms, the number of DMARD ever taken (2.8 and 2.5); 86% and 84% had ever used methotrexate and the use of methotrexate covered similarly 32% and 30% of disease 1669