New ACR/EULAR 2010 Classification Criteria for Rheumatoid Arthritis (RA)
European and American rheumatologists have established new criteria for the classification of rheumatoid arthritis (RA). The Revised Classification Criteria for Rheumatoid Arthritis will appear in the September issue of Arthritis & Rheumatism; they can also be viewed online or as a free download at the ACR homepage (accessed 23/08/2010).
What are the ACR / EULAR recommendations all about?
The declared goal and purpose of the new criteria are to make it possible to carry out scientific studies about the treatment of rheumatoid arthritis (RA) in early undifferentiated (!) stages of the disease. This has previously not been possible because hard and fast criteria for the definition of early rheumatoid arthritis were completely absent. To make clear what the intention of the ACR / EULAR criteria is, here I copied the article’s abstract in extract: “The work focused on identifying, among patients newly presenting with undifferentiated inflammatory synovitis, factors that best discriminate between those who were and those who were not at high risk for persistent an/or erosive disease – this being the appropriate current paradigm underlying the disease construct “rheumatoid arthritis”. (in brief: a quick overview of the 2010 ACR / EULAR classification criteria for rheumatoid arthritis in tabular form is available on the ACR homepage.)
The team of authors, which included over 35 contributors, was led by Dr. Daniel Aletaha of the Univeristy Clinic of Vienna. The authors repeat frequently and unambiguously that the newly published document concerns criteria for the classification of rheumatoid arthritis, not its diagnosis. At the same time, the authors are fully aware that their recommendations may in the future also be incorporated in making diagnoses in rheumatology practices – what was also the case for the ACR criteria of 1987, and these were also formally meant to establish criteria for the classification of RA.
The publication that includes the criteria (the full title of the article is 2010 Rheumatoid Arthritis Classification Criteria: An American College of Rheumatology/ European League Against Rheumatism Collaborative Initiative) also includes an extensive discussion of the fact that diagnosis can definitely be influenced by classification – though this must not necessarily be the case. According to the authors – whose list of names reads like a who-is-who of international rheumatology – from the very beginning they kept in view the fact that clinical rheumatologists must be able to fully identify with the new classification criteria. It is they, after all, who make the diagnosis of rheumatoid arthritis in their day-to-day practice and who must make decisions regarding treatment.
|The New ACR / EULAR Classification Criteria for Rheumatoid Arthritis 2010|
|The RA classification criteria 2010 cover four areas and establish a point value on a scale of 0 to 10. Every patient with a value of 6 or higher is classified as an RA patient.|
|► joint involvement – depending on the type and number of affected joints: up to 5 points|
|► serodiagnosis – (rheumatoid factors, ACPA determination): up to 3 points depending on titre levels|
|► acute phase reaction – elevated ESR value, elevated CRP value: 1 point|
|► duration of arthritis – symptoms longer than 6 weeks: 1 point|
Tuhina Neogi, MD, PhD, one of the authors and a member of the team of experts, is cited on this subject in a press release of the American College of Rheumatology:
Both scientific evidence and the experience of RA experts needed to be considered in the development of the new criteria to ensure all important factors were identified. Additionally, ensuring the new criteria reflects the opinions of front-line rheumatologists diagnosing and treating patients in clinical practice is key to their ultimate acceptance.
So, how do they work? – The ACR / EULAR Criteria 2010:
The 2010 ACR / EULAR Rheumatoid Arthritis Classification Criteria (excerpt on the ACR homepage) establish a point value between 0 and 10. Every patient with a point total of 6 or higher is unequivocally classified as an RA patient.
Four areas are covered in the diagnosis:
- joint involvement (depending on the type and number of joints, up to 5 points).
- serological parameters (including the rheumatoid factors as well as ACPA – “ACPA” stands for “anti-citrullinated protein antibody” – up to 3 points depending on titre level.
- acute phase reactants (1 point for elevated erythrocyte sedimentation rate, ESR, or elevated CRP value, CRP = c-reactive protein)
- duration of arthritis (1 point for symptoms lasting six weeks or longer).
Why the differentiation between classification and diagnosis?
The classification of a disease is aimed at making only very small mistakes within a group of individuals – a crucial criterion for the conception and design of a scientific study. Without uniform and evaluated standards, the comparison of different studies is strictly impossible.
For an individual, in the case of a single patient, rigid classification criteria can occasionally lead to a false positive or false negative result. In the end, adequate medical diagnosis is a highly individual process that does not follow strict rules and must take far more into account than a pure sum of the symptoms. Clinical diagnoses can only rarely be made based on formal criteria. (Indeed, a computer would be able to manage this, being, if possible, more exact than a diagnosing physician.)
RA diagnosis remains in the hands of the rheumatologist!
In other words: Despite the introduction of the new criteria, making the diagnosis of rheumatoid arthritis is clearly left up to the rheumatologist.
The new ACR / EULAR classification criteria are an important support for making a clinical diagnosis in any case; under some circumstances, they correctly assure the physician that the diagnosis is correct. This was also true of the “old” ACR criteria of 1987.
What does this mean for those who are not rheumatologists? For general practitioners, for internists who work in general practice, or for orthopaedists? –For these health workers, the same criteria remain in place for suspicion of RA. For German physicians, these are the RA criteria of the German Society for Rheumatology (Deutsche Gesellschaft für Rheumatologie, DGRh), pending further notice:
- two or more swollen joints
- morning stiffness lasting more than one hour
- the detection of rheumatoid factors or autoantibodies against certain ACPA can confirm the suspicion of rheumatoid arthritis – BUT: a negative autoantibody result does not exclude a diagnosis of RA!
(This is according to DGRh-Leitlinie: Management der frühen rheumatoiden Arthritis [DGRh guidelines: Management of early rheumatoid arthritis].)
Why establish new criteria?
In the last 20 years, a growing understanding of rheumatoid arthritis (see my blog post of 03/05/2010: 10 Facts about Rheumatoid Arthritis: The Clinical Understanding of the Disease) the rapid and more effective use of disease-modifying anti-rheumatic drugs, or DMARDs, (see my blog post of 18/06/2010: DMARDs: Practical Recommendations for Rheumatoid Arthritis Treatment), and completely new pharmacological treatment options (biologicals) have led to enormous progress for affected patients. Thanks to improved diagnostics (early diagnosis!) and enormous progress in treatment, structural damage to the joints can now be widely avoided, or at least significantly slowed.
Destruction of the joints viewed in radiological images was a significant point of the old ACR criteria from 1987. However this is just the type of damage that treatment is meant to avoid! – Gilllian Hawker, MD, senior author of the 2010 criteria, describes the previous dilemma of rheumatologists as follows (this citation is also from the ACR press release):
The 1987 criteria actually posed a major barrier to the study of treatments designed to prevent joint damage in rheumatoid arthritis. Many patients did not fulfill the previous RA classification criteria until their disease was well-advanced, and – in many cases – joint damage had already occurred.
Also according to Dr. Gillian Hawker, this “has completely hindered rheumatology research and rheumatologists in the development of effective strategies for the treatment of early rheumatoid arthritis” alongside novel treatment methods for established RA, which could avoid the irreparable consequences of this autoimmune disease.
What’s new in the “new criteria”?
The new criteria have given serology significantly more weight in the diagnosis of RA. According to the new ACR / EULAR criteria, a highly positive rheumatoid factor or highly positive ACPA titre (the acronym “ACPA” stands for “anti-citrullinated protein antibodies”) give half of the point total (3 points out of 6!) necessary to classify an individual as an rheumatoid arthritis patient. Only the rheumatoid factors were mentioned in the 1987 ACR criteria. (I recommend the following review articles about the importance of ACPA for the diagnosis of rheumatoid arthritis, both are free full text articles, accessed 24/08/2010: The Serological Diagnosis of Rheumatoid Arthritis – Antibodies to Citrullinated Antigens, by Karl Egerer, Eugen Feist and Gerd-Rüdiger Burmester, published in Deutsches Ärzteblatt in English and in German (!) (Serologische Diagnostik der rheumatoiden Arthritis: Antikörper gegen citrullinierte Antigene) and the Arthritis Research & Therapy article, The Use of Citrullinated Peptides and Proteins for the Diagnosis of Rheumatoid Arthritis).
The goal of rheumatologic treatment today is clearly remission of rheumatoid arthritis – and this requires an early and timely diagnosis of this autoimmune disease (early RA diagnosis, and early RA clinic appointment!). To make this possible, rheumatologists today have access to far more sensitive instruments and criteria for the classification and diagnosis of rheumatoid arthritis than even a few years ago!
This medical progress of the last twenty years is taken into account by the new classification criteria. They will unquestionable ring in a new era in rheumatology, and indeed a paradigm shift in diagnosing RA and treating that debilitating autoimmune disease. With the help of the classification criteria early and timely diagnosis of rheumatoid arthritis will be achieved.
What is next?
In the future, the new ACR / EULAR criteria will also be incorporated into the inclusion criteria for new clinical studies of rheumatoid arthritis (RA). The authors of the 2010 ACR / EULAR study freely admit that this will lead to some difficulties and a necessary learning process in the next few years. The new method for selecting patients for scientific studies will mean that the new patient populations will not be comparable to those in past RA studies. It will thus be difficult to compare the results of the new upcoming rheumatoid arthritis studies with those of the last few years.
One solution, according to the authors, could be a sort of transitional phase. They recommend that for the next few years, a certain percentage of patients who meet the old 1987 classification criteria be included in all studies – until everyone has adjusted to the new RA classification criteria. In certain situations it may even be logical to carry out corresponding subgroup analyses.
Weblinks (accessed 24/08/2010):
- American College of Rheumatology, or: ACR
- Deutsche Gesellschaft für Rheumatology, DGRh [German Society for Rheumatology]
- European League Against Rheumatism, EULAR
- Research Update about ACPAs, posted on ORGENTEC Autoimmunity Blog on 11/03/2010
- ORGENTEC Literature Service:recommended reading on anti-mutated citrullinated vimentin antibodies (Anti-MCV) and anti-citrullinated protein antibodies (ACPA) on the ORGENTEC website
.Author of this article: Tobias Stolzenberg
Literature (accessed 24/08/2010):
- Aletaha D, Neogi T, Silman AJ, Funovits J, Felson DT, Bingham CO 3rd, Birnbaum NS, Burmester GR, Bykerk VP, Cohen MD, Combe B, Costenbader KH, Dougados M, Emery P, Ferraccioli G, Hazes JM, Hobbs K, Huizinga TW, Kavanaugh A, Kay J, Kvien TK, Laing T, Mease P, Ménard HA, Moreland LW, Naden RL, Pincus T, Smolen JS, Stanislawska-Biernat E, Symmons D, Tak PP, Upchurch KS, Vencovsky J, Wolfe F, Hawker G. The 2010 ACR-EULAR classification criteria for rheumatoid arthritis.
Ann Rheum Dis.Arthritis Rheum 2010 Sep;69(9):1580-8.
- Arnett FC, Edworthy SM, Bloch DA, McShane DJ, Fries JF, Cooper NS, Healey LA, Kaplan SR, Liang MH, Luthra HS. The American Rheumatism Association 1987 revised criteria for the classification of rheumatoid arthritis. Arth Rheum. 1988 Mar;31(3):315-24
- Egerer K, Feist E, Burmester G. The Serological Diagnosis of Rheumatoid Arthritis –Antibodies to citrullinated Antigens [Serologische Diagnostik der rheumatoiden Arthritis: Antikörper gegen citrullinierte Antigene]. Dtsch Arztebl Int 2009; 106(10):159-63. Review – doi:10.3238/arztebl.2009.0159
- Pruijn GJ, Wiik A, van Venrooij WJ. The use of citrullinated peptides and proteins for the diagnosis of rheumatoid arthritis. Arthritis Res Ther. 2010;12(1):203. Review.
- van Schaardenburg D, Dijkmans BA. A welcome address for the new criteria. Editorial. Ann Rheum Dis 2010;69:1577-1579 – doi:10.1136/ard.2010.135335
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