Assesement of joint pain and disease activity in rheumatoid arthritis patients

Abstract

Rheumatoid arthritis (RA) is a chronic autoimmune disease of synovial joints characterized by joint pain, swelling and morning stiffness. Disease modifying anti rheumatoid drugs (DMARDs) are the mainstay of treatment in RA. Visual analog pain scale (VAS) and Activities of Daily Living (ADL) pain scales are tools used for objective measurement of joint pain in RA. DAWN DAS 28(3) calculator is used to calculate the disease activity in RA patients. Objectives of this study were to assess the joint pain and disease activity and their correlation in a group of RA patients attending the Rheumatology clinic, Teaching hospital, Peradeniya.

Following initial screening of 80 RA patients who were on DMARDs, 67 patients who had ESR reports were included in the study. Joint pain using VAS and ADL scales and the disease activity using DAWN DAS 28(3) were assessed.

The gender ratio (male to female) was 1:16, the mean age was 53 years, the mean age at onset of the disease was 44.6 years and the mean disease duration was 9 years. Mean VAS pain score was 34.7 mm (out of 100 mm), the mean ADL pain score was 2.29 (out of 4) and the mean DAS 28 (3) was 4.23. In this sample, 22.4% (n =15) were in disease remission, 4.2% (n = 3) showed low disease activity, 50.7% (n =34) showed moderate disease activity and 22.4% (n = 15) had high disease activity. According to Pearson’s correlation analysis, DAS 28(3) was significantly correlated with VAS and ADL pain scales (r = 0.7204 and 0.5961, respectively) and VAS and ADL pain scores significantly correlated (r = 0.6212) with each other.

We conclude that the standard pain and disease activity scales are applicable in Sri Lankan RA patients. Both the disease activity and the pain scores correlate to each other reflecting the importance of effective control of disease activity.