What is remission?
Remission is a word that is used with diseases like cancer, Multiple Sclerosis (MS), and Rheumatoid Arthritis (RA) because no cure is yet known. Remission is a period of time when the disease is dormant or inactive. Spontaneous or natural remissions are rare with RA.
RA remission has been judged by diverse methods in the past. A single RA patient may be assessed as in remission or acute disease activity by different doctors. In 2010, the American College of Rheumatology (ACR) created two provisional sets of remission criteria for Rheumatoid Arthritis which could be a step toward standardization:
- Tender joint count, swollen joint count (using the 28 joint-count scale), C-reactive protein (in mg/dl), and patient global assessment scores (on a scale of zero to 10) are all less than or equal to one.
- Simplified Disease Activity Index (which adds the scores from the four outcome measures above plus a physician global assessment to create one number between zero and about 100) score is less than or equal to 3.3.
What about clinical remission?
Sometimes the phrase clinical remission is used to refer to a state of very low disease activity sustained by medication. It is different from spontaneous remission which occurs naturally. It may also be different from complete remission because the patient may still experience some progress of the disease.
A study published by Dr. Andy Brown in 2006 clearly illustrated that 96% of RA patients regarded as clinically normal (no external evidence of swollen joints) were proven to have synovitis using magnetic resonance imaging (MRI). The study includes images, presented at the 2006 American College of Rheumatology (ACR) Scientific Meeting, which also demonstrate that 46% of patients in clinical remission had bone marrow edema. Also, 73% had synovial hypertrophy according to ultrasound gray-scale imaging. (See screenshot below of MRI and ultrasound images from the Brown remission study.)
The words edema and synovitis both are indicative of inflammation. Researchers suspect that inflammatory activity is responsible for structural damage. Unfortunately, inflammatory activity continues inside of the tissues of RA patients even when obvious external inflammation (i.e.: swelling) is reduced.
How common is remission with Rheumatoid Arthritis?
Since not all rheumatologists agree about how to assess remission, it is difficult to know how frequently it occurs. Some clinical trials use standards that allow for 30 to 50 percent of patients to be labeled as achieving clinical remission during a trial. However, patients communicate a much different result. The National Databank of Rheumatic Diseases estimates that only six percent of RA patients surveyed are in a state of remission.
More reading on RA remission classification:
Read the Brown clinical remission study with graphs and images: Presence of Synovitis in Rheumatoid Arthritis Patients with Disease Modifying Antirheumatic Drug-Induced Clinical Remission