RA individuals from lower GDP countries keep working despite worse symptoms than richer countries

Copenhagen, Denmark, Friday 12 June 2009: Individuals diagnosed with rheumatoid arthritis (RA) in lower gross domestic product (GDP) countries (GDP below $11,000) are more likely to continue working despite higher disease activity and functional disability scores compared to their counterparts in higher GDP countries (GDP >$24,000) according to a new multinational study presented today at EULAR 2009, the Annual Congress of the European League Against Rheumatism in Copenhagen, Denmark. Among 1,650 individuals from 30 countries whose symptoms had begun during the 2000's and who remained working after RA diagnosis, disability levels according to the Health Assessment Questionnaire (HAQ*) were 0.25 vs. 0.82 in men and 0.50 vs. 0.94 in women (p<0.001) in higher-GDP and lower-GDP countries, respectively, and the Disease Activity Scores (DAS28**) were 3.1 vs. 4.7 in men, and 3.5 vs. 4.8 in women (p<0.001). A Kaplan-Meier analysis (95% CI) showed that the probability of individuals continuing work for 2 years was 80% and the probability of continuing to work for 5 years was 68%.

Dr Tuulikki Sokka, Jyväskylä Central Hospital, Finland, who leads the project said: "Work disability is the most costly consequence of RA, and the rheumatology community would welcome better treatment strategies to effectively address this. However, real-life data from 30 countries indicate that work disability is still a major issue in early RA during this decade, and especially in low-GDP countries where people continue to work with considerable disease activity and functional limitations."

The results of the study showed that, at the time of symptom onset, 68% (<65 years) of subjects were working, but 35% of these reported that they subsequently became 'work disabled' due to RA. Notably, this proportion of people with RA was similar in both lower and higher GDP countries at 5 years.

Subjects for the study were derived from The Quantitative Standard Monitoring of Patients with RA (QUEST-RA) database of 7,568 patients (80% females, mean age 56 years, mean disease duration 11 years) who receive standard care from rheumatologists. Patients from 83 sites in the following 30 countries were studied: Argentina, Brazil, Canada, Denmark, Egypt, Estonia, Finland, France, Germany, Greece, Hungary, India, Ireland, Italy, Japan, Kosovo, Latvia, Lithuania, Morocco, the Netherlands, Norway, Poland, Russia, Serbia, Spain, Sweden, Turkey, United Arab Emirates, United Kingdom, and the United States.

In the study, HAQ (0-3) was used to measure everyday disability and the DAS28 (0-10) to measure disease activity. Data concerning work status/disability were based entirely on results of a patient self-reporting questionnaire which included multiple choice questions about work status at the time of the first symptoms of RA compared to current work status. Patient self-perceived work disability was queried with questions such as: 'Are you work disabled because of RA?' 'If so, since when?' Kaplan-Meier statistics were applied to measure the survival function of the data over time.

* HAQ (Health Assessment Questionnaire) is a patient self-report questionnaire to measure an individual's physical functioning. It assesses ability to undertake everyday activities such as dressing, eating and walking, and whether assistance from another person or disability aids is required. A higher score indicates greater disability.

** DAS28 (Disease Activity Score) is an index used by physicians to measure how active an individual's RA is. It assesses number of tender and swollen joints (out of a total of 28), the erythrocyte sedimentation rate (ESR, a blood marker of inflammation), and the patient's 'global assessment of global health'. A higher score indicates more active disease.

Source: European League Against Rheumatism