In the September issues of their journals Arthritis and Rheumatism and Annals of the Rheumatic Diseases the American College of Rheumatology (ACR) and the European League Against Rheumatism (EULAR) present a new set of criteria for the classification of rheumatoid arthritis (RA).
Why do wee need “new” criteria for the classification of RA?
The 1987 ACR criteria have been criticised for their lack of sensitivity, especially in early disease. They rather describe the symptoms of fully developed late-stage RA. During the past decade, RA treatment has undergone dramatic changes providing previously unforeseen therapeutic dimensions. New and highly effective DMARDs have continued to emerge and treatment strategies have changed during this period, initially by calling for early referral and early institution of DMARD treatment.
For this reason, the current EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs already include two important postulations:
1. Treatment with synthetic DMARDs should be started as soon as the diagnosis of RA is made, and that
2. Treatment should be aimed at reaching a target of remission or low disease activity as soon as possible in every patient; as long as the target has not been reached, treatment should be adjusted by frequent (every 1–3 months) and strict monitoring
How have the new criteria been developed?
A joint working group from the ACR and the European League Against Rheumatism developed, in three phases, this new approach to classifying RA. They re-evaluated patient data of nine early arthritis cohorts and investigated among those patients newly presenting with undifferentiated inflammatory synovitis, factors that best discriminated between those who were and those who were not at high risk for persistent or erosive disease. The relative weight of each of these factors was also determined.
This resulted in a new criteria set, confirming definite RA in a group of patients that present with symptoms of synovitis in at least one joint, with the synovitis not better explained by an alternative diagnosis.
These patients must achieve a total score of 6 or greater (of a possible 10) from the individual scores in four domains:
- number and site of involved joints (range 0–5),
- serological abnormality (range 0–3),
- elevated acute-phase response (range 0–1)
- symptom duration (two levels; range 0–1).
2010 ACR – EULAR Classification Criteria for Rheumatioid Arthritis
Daniel Aletaha and his co-authors state in their conclusion:
This new classification system redefines the current paradigm of RA by focusing on features at earlier stages of disease that are associated with persistent and/or erosive disease, rather than defining the disease by its late-stage features. This will refocus attention on the important need for earlier diagnosis and institution of effective disease-suppressing therapy to prevent or minimise the occurrence of the undesirable sequelae that currently comprise the paradigm underlying the disease construct ‘RA’.
What is really new?
- Scoring system counting points according to the relative weight of the parameters under examination – six out of ten possible points define RA and fix the point for initiation of DMARD therapy
- Definition of a selected group of patients to whom the criteria are applicable
- More differentiated view on the joints: large joints are now included (with lower relative weight compared to small joints); symmetric disease is no longer required; joint involvement may count up to five points
- Serology becomes more important; new criteria distinguish low titers of ACPA/RF from high titers; high titers of autoantibodies add three points to the score, – that is already half of the required six points for definite classification
- Acute phase reactants are now included; at least one abnormal result for ESR or CRP counts for one point.
Important note: The new ACR-criteria are NOT tools for diagnosis of RA, they are intended to discriminate between patients with high or low risk of persistent erosive disease.
As the authors state:
The goal set forth was to develop a set of rules to be applied to newly presenting patients with undifferentiated synovitis that would
- identify the subset at high risk of chronicity and erosive damage;
- be used as a basis for initiating disease modifying therapy; and
- not exclude the capture of patients later in the disease course.
It is important, however, to stress that the criteria are meant to be applied only to eligible patients, in whom the presence of obvious clinical synovitis in at least 1 joint is central. They should not be applied to patients with mere arthralgia or to normal subjects.
Comments from the rheumatology community:
In their “welcome address for the new criteria” Dirkjan van Schaardenburg and Ben A.C. Dijkmans from the Netherlands point out the following aspects:
The fundamentally different approach to the classification of RA, as was made quite clear, is the novel practical focus on recognising early disease with a poor prognosis. When we look at the separate new criteria, the most conspicuous newcomer among them is ACPA, which adds for the first time a pathogenetic element to the criteria. ACPA proved to have the strongest relation of all the examined biomarkers to the gold standard of methotrexate use, and was shown before to be among the most powerful of prognostic factors in RA.
Conversely, lack of fulfilment of the criteria could lead to a more conservative treatment policy in patients who do not cross the line of the required 6-point score. This does not need to be a problem since patients can fulfil the criteria at any later point in time should their disease become more active. How far patients with arthritis who do not fulfil the criteria over a longer period and do not receive treatment are at risk of developing erosions needs to be studied.
The expectation is that the new criteria will be more sensitive, especially in early disease, leading to more patients with RA with mild disease.
Stanley Cohen from Texas, USA, and Paul Emery, United Kingdom refer to the impact of the new criteria on primary care decisions:
Additional concerns exist regarding the utility of these classification criteria for the primary care physician who must determine synovitis by examination and then exclude other possible diagnoses that might explain the synovitis. The authors correctly point out that the criteria are not to be used as a tool for referral of patients with inflammatory arthritis to the rheumatologist, and there are several ongoing efforts in progress to provide primary care practitioners with the tools to recognise patients who need rapid, early referral.
And they dare an optimistic foresight:
The acceptance of the evolving nature of RA is a step-change conceptually. We look forward to the identification of future biomarkers that will again result in another call to modify the RA classification criteria. When that occurs, improvement in the quality of life of our patients will surely follow.
Reference List
(1) Smolen JS, Landewe R, Breedveld FC, Dougados M, Emery P, Gaujoux-Viala C et al. EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs. Ann Rheum Dis 2010; 69(6):964-75.
(2) Funovits J, Aletaha D, Bykerk V, Combe B, Dougados M, Emery P et al. The 2010 American College of Rheumatology/European League Against Rheumatism classification criteria for rheumatoid arthritis: Methodological Report Phase I. Ann Rheum Dis 2010; 69:1589-95.
(3) Aletaha D, Neogi T, Silman AJ, Funovits J, Felson DT, Bingham CO, III et al. 2010 Rheumatoid arthritis classification criteria: an American College of Rheumatology/European League Against Rheumatism collaborative initiative. Ann Rheum Dis 2010; 69(9):1580-8.
(4) Aletaha D, Neogi T, Silman A, Funovits J, Felson DT, Bingham CO et al. 2010 Rheumatoid arthritis classification criteria: An American College of Rheumatology/European League Against Rheumatism collaborative initiative. Arthritis & Rheumatism 2010; 62(9):2569-81.
(5) van Schaardenburg D, Dijkmans BAC. A welcome address for the new criteria. Ann Rheum Dis 2010; 69:1577-9.
(6) Cohen S, Emery P. The American College of Rheumatology/European League Against Rheumatism Criteria for the classification of rheumatoid arthritis: a game changer. Ann Rheum Dis 2010; 69(9):1575-6.
are the diagnostic criteria for RA still to be used for diagnosis?
Thanks for this important comment,
as it opens the opportunity to clear an (unavoidable?) misunderstanding.
No, the 2010 ACR / EULAR classification criteria for rheumatoid arthritis are not intended for diagnosing rheumatoid arthritis in clinical practice! The declared goal of the new criteria is to identify early rheumatoid arthritis in order to carrying out scientific studies on RA treatment.
Why this differentiation between classification and diagnosis is crucial? – In a nutshell: For a single patient rigid classification criteria can occasionally lead to a false positive or a false negative result. Finally, the adequate medical diagnosis is a highly individual process which doesn’t follow strict rules. Regular clinical diagnosis have to take much more into account than the pure sum of the symptoms and can only rarely be made based on formal criteria. (On this please see my article posted on 24/08/2010: New Criteria for the Classification of Rheumatoid Arthritis: http://autoimmunityblog.wordpress.com/2010/08/24/new-2010-acr-eular-classification-criteria-for-rheumatoid-arthritis-orgentec-autoimmunity-blog/ – in that post I elaborate on this topic.)
Thanks for the comment – stay curious!
Best wishes
Tobias Stolzenberg