The number of involved joints has been a diagnostic feature that has held up insurance coverage for some patients, with insurers insisting that patients meet the 1987 standard of at least six involved joints, Dr. Weinblatt said. Dr. Furst and Dr. Matteson also cited experiences with denied insurance coverage, something they anticipate will become a thing of the past, more or less, with the new criteria.
“The first thing insurers ask in prior authorization forms is whether a patient meets the criteria for RA,” Dr. Weinblatt noted. This slowed the use of disease-modifying antirheumatic drugs in some patients. The new criteria will eliminate this barrier in many cases, he said.
Although all the experts who were interviewed agreed that the new criteria accurately reflected current thinking on what constitutes RA, a few envisioned certain situations that could cause problems. One concern involved mixing apples and oranges: Could results from RA patients in prior treatment studies always be appropriately applied to patients whose disease is defined by the new criteria? Dr. Furst asked. Similarly, he wondered whether drug toxicity profiles that were worked out in prior cohorts of RA patients would match the toxicities faced by newly defined RA patients.
Dr. Mease said he was concerned about a group of patients who are sick but fall short of the diagnostic criteria. These are the patients who present with fewer than 10 involved medium or large joints, low titers of rheumatoid factor and anti–citrullinated protein antibody, and a very high level of C-reactive protein, a constellation showing that the patient “clearly has an inflammatory process,” yet one that would tally a diagnostic score of 4-5 points (depending on symptom duration), which is less than the 6 points needed for a definitive RA diagnosis. Despite such concerns, Dr. Furst noted that the 2009 criteria had higher specificity and sensitivity than did the 1987 criteria. Also, new serologic and genomic tests that will likely emerge in the next several years will further refine diagnoses and will be incorporated into the scoring formula, Dr. Mease said.
“I think it will improve the outcome of our patients, and so it's a very good thing,” said Dr. Furst. The new criteria will become widely adopted because “all of us who talk about it will insist on it. But I bet it will take longer than we'd like.”
Dr. Bingham and Dr. Mease participated on the panel that developed the criteria; this work was sponsored by the ACR and EULAR.
The rheumatologists who were interviewed said that because the new criteria do not deal directly with treatment, they did not have relevant disclosures on the topic.
The new EULAR/ACR criteria aim to diagnose rheumatoid arthritis before formation of bone erosions, as shown here.
Source ©J. Cavallini/Custom Medical Stock Photo
The New Criteria in Brief
Patients are definitively diagnosed with RA if they score 6 or more points according to these criteria:
Joint Involvement
▸ 1 medium-large joint (0 points)
▸ 2-10 medium-large joints (1 point)
▸ 1-3 small joints (2 points)
▸ 4-10 small joints (3 points)
▸ More than 10 small joints (5 points)
Serology
▸ Not positive for either rheumatoid factor or anti–citrullinated protein antibody (0 points)
▸ At least one of these two tests are positive at low titer, defined as more than the upper limit of normal but not higher than three times the upper limit of normal (2 points)
▸ At least one test is positive at high titer, defined as more than three times the upper limit of normal (3 points)
Duration of synovitis
▸ Lasting fewer than 6 weeks (0 points)
▸ Lasting 6 weeks or longer (1 point)
Acute phase reactants
▸ Neither C-reactive protein nor erythrocyte sedimentation rate is abnormal (0 points)
▸ Abnormal CRP or abnormal ESR (1 point)
Note: Patients receive the highest point level they fulfill within each domain. For example, a patient with five small joints involved and four large joints involved scores 3 points, according to the criteria.
Note: Based on presentation by Dr. Hawker at the annual meeting of the American College of Rheumatology, October, 2009.