Patient-reported outcomes hardly predict RA change in disease activity
It appears that patient-reported pain, stiffness and fatigue at baseline offer limited value for the prediction of changes in disease activity and activity limitation in early rheumatoid arthritis (RA), according to a recent study.
Researchers recruited cases (n=1,415) to the Yorkshire Earl Arthritis Register between 1997 and 2009 to evaluate patient-reported variables as predictors of change in disease activity and disability in RA. Multilevel models were used to identify Predictors of the 28-joint Disease Activity Score (DAS28) and the Health Assessment Questionnaire-Disability Index (HAQ-DI) at baseline and change over 12 months.
The baseline predictors were the following: age, sex, symptom duration, autoantibody status, pain and fatigue visual analogue scales (VAS), DAS28, HAQ-DI, and duration of early morning stiffness (EMS).
Women had slower rates of change than men: DAS28 dropped by 0.19 and 0.17 units/month, and HAQ-DI by 0.028 and 0.023 units/month in men and women, respectively. The effects of baseline pain and EMS on rates of change were small, while fatigue VAS was only associated with DAS28 and HAQ-DI at baseline.
In patients recruited up to 2002, those with greater pain at baseline reduced DAS28 more quickly (by 0.01 unites/month of DAS28 per cm pain VAS; p=0.024). In patients recruited after 2002, there was a stronger effect for pain (by 0.01 units/month; 0.087).
Reduction in DAS28 was greater with longer EMS. In both cohorts, patients with longer EMS duration had greater reduction in HAQ-DI (p=0.006). However, pain and fatigue were not significant predictors of change in HAQ-DI, according to researchers.