MS3: CORRELATION OF A GENERIC HEALTH-RELATED QUALITY OF LIFE QUESTIONNAIRE AND SELF-ADMINISTERED RHEUMATOID ARTHRITIS DISEASE ACTIVITY INSTRUMENT

Abstract

BACKGROUND: Health-related quality of life (HR-QOL) measures have been used to study the impact of disease activity in patients with rheumatoid arthritis (RA). The objective of this study was to evaluate the correlation between SF-36 scales, physical function (PF), role physical (RP) and bodily pain (BP) and Rapid Assessment of Disease Activity in Rheumatology (RADAR). METHODS: Baseline data was analyzed from the Study of New Onset Rheumatoid Arthritis (S.O.N.O.R.A.SM), a 5-year prospective, longitudinal, inception cohort study to document long-term functional, clinical, and humanistic outcomes and patterns of treatment in patients with new onset rheumatoid arthritis. Baseline data collection consisted of RADAR and SF-36 via telephone interviews by trained interviewers. To assess the correlation, Pearson product moment correlation coefficients were calculated. RESULTS: One hundred thirty-one patients completed the baseline survey. Mean age of the sample was 56 years; 78% were female; 82% were Caucasian. SF-36's PF, RP, and BP scales had means of 54 (SE = 0.02), 31 (SE = 0.03), and 47 (SE = 0.02), respectively. Mean scores for RADAR items were 7.2 (SE = 0.22) for “arthritis activity over the past 6 months (AA6M)”, 4.9 (SE = 0.23) for “arthritis activity today (AAT)”, 4.2 (SE = 0.22) for “arthritis pain today (APT)”, and 2.6 (SE = 0.15) for “morning stiffness today (MST)”. SF-36's PF scale correlated with AA6M (r = 0.39, p < 0.001), AAT (r = 0.49, p < 0.001), APT (r = 0.51, p < 0.001), and MST (r = 0.40, p < 0.001). SF-36's RP scale correlated with AA6M (r = 0.37, p < 0.001), AAT (r = 0.38, p < 0.001), APT (r = 0.44, p < 0.001), and MST (r = 0.33, p < 0.001). SF-36's BP scale correlated with AA6M (r = 0.50, p < 0.001), AAT (r = 0.48, p < 0.001), APT (r = 0.59, p < 0.001), and MST (r = 0.42, p < 0.001). CONCLUSION: The SF-36's BP domain resulted in the highest correlation with RADAR items. The APT item of RADAR had the highest correlation with all three domains of SF-36. These results suggest that the level of bodily pain is indicative of functioning and well-being of patients.