Background/Purpose: Rheumatoid arthritis (RA) patients score their global disease activity (ptGD) on average higher than physicians (phGD). This difference can vary between countries with high and lower gross national income (GNI). Also, patients with RA in lower GNI countries have less access to biologic disease modifying anti rheumatic drugs (bDMARDs) and synthetic (cs)DMARDs. With targeted treatment aiming at low disease activity (LDA) or remission, this could influence treatment. The aim was to compare differences between ptGD and phGD in high and lower GNI countries and to assess if potential differences are associated with disease activity measures.

Methods: RA patients included in the METEOR database were selected from countries ≥30 patients with >1 visit, available phGD and disease activity score (DAS) or DAS28. Countries were divided in high and lower GNI (World Bank definition, high income GNI per capita ≥$12746). ptGD and phGD were measured on a 100 mm visual analogue scale (100 worst score). A difference ≥20 mm between ptGD and phGD (GDdif=ptGD–phGD) was considered clinically relevant. Susequently, ptGD was artificially substituted by phGD in the DAS and DAS28, in order to assess the potential influence of the discrepancies in globals on the number of patients in LDA or remission.

Results: From high GNI countries 6928 patients were included, from lower GNI countries 5136 patients. DAS was available in 10420 patients (6179 from high GNI countries), DAS28 in 11173 patients (6839 from high GNI countries). Patients from lower GNI countries had higher disease activity [mean (SD) DAS28 4.6 (1.8) vs 3.4 (1.8); DAS 2.5 (0.9) vs 1.8 (0.9)], longer disease duration at diagnosis [55 (69) vs 27 (59) weeks] and less often reached LDA [DAS28 49% vs 75%; DAS 20% vs 48%] or remission [DAS28 7% vs 32%; DAS 20% vs 48%] than patients from high GNI countries. Compared to high GNI countries, in lower GNI countries, more patients had a GDdif ≥20mm with ptGD>phGD (44% vs 30%) and fewer patients had a GDdif <20mm (47% vs 67%). Also, more patients had a GDdif ≥20mm with ptGD<phGD (9% vs 3% in lower vs high GNI countries). Replacing ptGD by phGD resulted in a mean (SD) change in DAS and DAS28 of 0.09 (0.1) and 0.4 (0.6) in high GNI countries and 0.9 (0.1) and 0.4 (0.7) in lower GNI countries. For both DAS and DAS28, the percentage of patients changing disease activity status is low in all countries, with most patients gaining LDA or remission (fig 1).

Conclusion: Compared to high GNI countries, patients from lower GNI countries had higher disease activity and less often reached LDA or remission. Clinically relevant differences between ptGD and phGD were found in more than 1/2 of the patients in lower GNI countries and in 1/3 of the patients in high GNI countries, with potentially more impact on disease activity assessments in lower GNI countries than in high GNI countries. These results give further support to observations that  access to ‘good RA care’ is worse in lower than higher GNI countries (inequity).