ACR endorses standardized measures to determine rheumatoid arthritis disease activity

A working group convened by the American College of Rheumatology (ACR) has evaluated more than 60 disease activity measures for rheumatoid arthritis (RA). The group narrowed the number of RA disease activity measures and the recommended six for use in U.S. clinical practice are detailed in Arthritis Care & Research, a journal published by Wiley-Blackwell on behalf of the ACR.

RA is a systemic inflammatory disease, affecting more than 1 million Americans according to ACR estimates. Medical evidence has shown significant improvement in RA treatment over the last two decades, making disease remission possible for many patients. While many health care stakeholders advocate standardized assessments for RA disease activity, uniform measures of RA activity are not currently used by U.S. rheumatologists.

To address this important issue, the RA Clinical Disease Activity Measures Working Group systematically reviewed medical literature to identify disease activity measures for RA. The group surveyed rheumatologists for input and used this feedback along with psychometric analysis to determine recommendations for RA disease activity assessments.

"Our goal was to determine which RA disease activity measures could accurately distinguish the various levels of RA activity, and would also be reasonable to implement in clinical practice," explains Salahuddin Kazi, M.D., with Dallas VA Medical Center in Texas and one of the lead researchers involved with the working group. The group identified 63 RA disease activity measures, narrowing that down to 14 measures for further evaluation by practicing rheumatologists.

Feedback from the rheumatologists determined that 9 measures would be most useful and feasible in a clinical setting. The working group then selected 6 disease activity measures based on their reliability, validity and responsiveness. The ACR-approved recommendations for RA disease activity measures include:

• Clinical Disease Activity Index (CDAI)
• Disease Activity Score with 28-joint counts (erythrocyte sedimentation rate or C-reactive protein) (DAS-28)
• Patient Activity Scale (PAS)
• PAS-II
• Routine Assessment of Patient Index Data with 3 measures (RAPID 3)
• Simplified Disease Activity Index (SDAI)

In a related article, "2012 Update of the 2008 American College of Rheumatology Recommendations for the Use of Disease-Modifying Antirheumatic Drugs and Biologic Agents in the Treatment of Rheumatoid Arthritis," Singh et al. include the RA disease activity measures (Table 3) to guide clinicians in selecting the appropriate treatment options for their patients. "Rheumatologists are tasked with treating to target, and one or more of these disease activity measures will help determine the level of RA disease activity in the patient," said Dr. Kazi. "

The measures recommended to determine RA disease activity are sensitive to change, can discriminate between low, moderate, and high disease activity states, include remission criteria, and are feasible to perform in a clinical setting," concludes Dr. Kazi. "Incorporating standardized disease activity measures will facilitate adherence to the ACR guidelines for treating RA and aid clinicians in providing quality care to their patients with RA."