I asked Dr. Hawker of the differences between the old and new criteria and although it turned out to be like asking someone to compare apples and oranges, she mentioned four primary differences
1. "The new criteria do not incorporate x-ray damage (erosions) or nodules, or other late stage RA changes, as the intent is to identify and treat people early so as to prevent easily changes";
2. the new criteria do not include how long a person has experienced joint stiffness or symmetry of joint involvement as neither have been identified by "current evidence as predictive of subsequent development of persistent or erosive RA";
3. the new criteria "incorporate new knowledge about the role of anti-citrullinated protein/peptide antibodies (ACPA) in predicting prognosis in RA";
4. "a greater number of subjects with early RA will meet the new criteria than the old criteria - this will enabling inclusion of such patients in future clinical trials of new therapeutics for RA."
Not surprisingly, some doctors are adapting these new criteria for use in a clinical setting as a diagnostic aid. Dr. Hawker emphasizes that "the focus of this endeavor was not on developing diagnostic criteria for RA. A separate body of work is required to develop such tools which may be informed by these new classification criteria." However, should clinicians be guided in their practice by the new criteria, it is important to emphasize that "all synovial joints that may be affected in RA other than those that are typically affected by osteoarthritis (this is the base of the thumb, big toe and the end joints of the fingers) should be considered in counting the number of 'involved joints' in the new criteria. Further, because physicians often have difficulty distinguishing swollen joint from one that is not swollen, the new criteria consider a joint as 'involved' or affected in the presence of tenderness OR swelling," Dr. Hawker states.
Dr. Hawker is optimistic about the impact of the new criteria on clinical trials, stating that the "reason for their development is to push our ability to study new therapies in RA early in the stage of the disease - that is, to see if we can actually prevent joint damage from occurring." As well, the advances in treatment of RA mean that "a separate task force has been working on the development of criteria for remission in RA."
On a personal note, I have had RA for over 40 years and the fact that not only has the therapeutic goal changed from slowing the progression of RA to preventing the kind of damage that are seen in all of my joints, but that we are now looking at criteria for determining remission is, to put it bluntly, blowing my mind. I never thought I would see such advances in my lifetime, but thanks to Dr. Hawker and others like her, we're now living in a whole new world.
Gillian A. Hawker, MD, MSc, is Professor of Medicine and Rheumatology in the Departments of Medicine and Health Policy, Management and Evaluation at the University of Toronto. She is a clinical epidemiologist and health services researcher who has focused her research on study of the access to, and outcomes of, clinical care for osteoarthritis, OA, and qualitative and quantitative research on the determinants and consequences of pain in OA.

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