With patients benefiting from the advent of biologics and a movement toward earlier, more aggressive treatment of rheumatoid arthritis (RA), a standardized set of criteria to define remission is now warranted, according to the authors of a new study published in the Journal of Rheumatology.1
Currently, reported rates of RA remission vary depending on the definition used. The current study sought to compare three different sets of criteria used to gauge remission, including: clinical remission (no tender or swollen joints and normal erythrocyte sedimentation rate); the American College of Rheumatology (ACR) criteria (which adds to the clinical criteria measures of pain and stiffness); and radiographic remission (no worsening of erosions and no new erosions from baseline).
The study initially enrolled 127 early RA patients, and remission was assessed at intervals up to 5-years in 111 patients. Of these, 17% met ACR remission criteria, 37% met clinical remission criteria, and 55% met the radiographic remission criteria. Only 12% patients met all three sets of remission criteria. Moreover, less than 50% in clinical remission at 2 years were still in remission at 5 years.
The absence of both inflammatory activity and radiographic progression may be the basis for the development of clinically relevant remission criteria for RA, conclude researchers led by Heidi Mäkinen, MD, rheumatologist at the Jyväskylä Central Hospital in Jyväskylä, Finland. "As the ultimate goal of treatment is to prevent serious long-term consequences of RA such as joint damage, the concept of radiographic remission cannot be ignored as a potential criterion for remission," the authors write.
Dr. Mäkinen tells CIAOMed that "the ideal criteria to define remission in RA should include disease activity, patients' function, and tissue damage caused by RA, and the European League Against Rheumatism (EULAR) and the ACR should develop and agree upon the idea."
Subjective definitions are clinically useful
"To a considerable extent, we have great difficulty agreeing on one definition [of remission], but we recognize it when we see it," Harold E. Paulus, MD, a rheumatologist at the University of California School of Medicine in Los Angeles writes in a previously released editorial.2
"The subjective definition is probably sufficient for clinical practice provided the three domains of RA [the signs and symptoms of inflammation, functional impairment, and structural damage to joints] are carefully considered for each patient," Dr. Paulus writes. Still, he suggests, more precise definitions would provide a common vocabulary and also offer tangible targets for drug developers.
Time for a consensus
"Remission criteria should be standard and should be something that most rheumatologists would agree to," says Yukiko Kimura, MD, chief of pediatric rheumatology at The Joseph M. Sanzari Children's Hospital of Hackensack University Medical Center in Hackensack, New Jersey.
To achieve this goal, Dr. Kimura suggests an international consensus meeting to develop criteria that would then require validation. "We want the criteria to be sensitive enough to pick up all patients with remission, but specific enough to predict the outcome of patients 5 years down the road," she says.
As a practicing rheumatologist, Dr. Kimura prefers the ACR criteria "because they seem to be the most stringent, but we are going to want to have a combination of clinical criteria like the ACR and to look at other things such as radiographic progression."
"Even just 10 years ago with the use of methotrexate, it was very difficult to get patients with RA into a remission-like state, and now it's a much more realistic possibility," Dr. Kimura says. She also points out that the data from Mäkinen et al are particularly interesting in that more patients achieved radiographic remission than one might predict. "We may be seeing more and more of that because biologic agents seem to be powerful at stopping radiographic progression."
References:
- Mäkinen H, Kautiainen H, Hannonen P, Sokka T. Frequency of remissions in early rheumatoid arthritis defined by three sets of criteria. A 5-year followup study. J Rheumatol. 2005;32:796-800.
- Paulus HE. Defining remission in rheumatoid arthritis: what is it? Does it matter? J Rheumatol. 2004;31:1-4.