Local Joint Inflammation Linked to Joint Damage Progression in RA

In patients with rheumatoid arthritis (RA), cumulative joint inflammation is associated with joint damage progression of the same joint, according to the results of a post hoc analysis published in RMD Open.

Using data from the BEST study (BehandelStrategieën, which is Dutch for “treatment strategies”), researchers explored whether the frequency of local joint inflammation in patients with RA was linked to radiographic joint damage progression in that particular joint. They also evaluated the association between cumulative joint tenderness in the absence of joint swelling and progression of joint damage. 

Patients with newly diagnosed RA were followed-up with for a period of
10 years, with trained nurses assessing joint swelling and joint tenderness every 3 months.

Cumulative joint inflammation was defined as the percentage of available study visits at which a joint was swollen. Clinical inflammation was defined as joint swelling (with or without joint tenderness).

Of a total of 473 participants with at least 1 year of available follow-up data, 377 (80%) had any radiographic damage at the end of follow-up. The median patient-level Sharp-van der Heijde score progression from baseline was 1.5 (range, 0-8.25).

Among the 15,846 joints examined, 2495 (16%) revealed radiographic joint damage (damage score of ≥0.5) at the end of follow-up. Damaged joints had a mean damage score of 2.5±3.5 (wrist excluded, 2.2±2.0).

Of the 2483 joints with damage at the end of follow-up, 1141 (46%) were swollen at baseline compared with 4725 (35%) of the joints without damage. Researchers observed joint swelling at 6% (range, 0%-17%) of visits for joints with damage and 3% (range, 0%-8%) for joints without damage.

Cumulative local joint swelling was associated with local progression of radiographic damage in the same joint (β=0.14; 95% CI, 0.13-0.15). This relationship was also reported in a subset of joints that were swollen at least 1 time. However, cumulative local joint tenderness without concurrent local joint swelling was less strongly associated with local radiographic progression of joint damage (β=0.04; 95% CI, 0.03-0.05).

Study limitations included that the researchers evaluated only the hand and foot joints and therefore were unable to draw conclusions about the association between clinical inflammation and joint damage in other joints; one-to-one comparisons of joint erosions and joint space narrowing could not be made; and the results were not replicated in a population with more joint damage.

The study authors concluded, “Further research is needed to find new treatment strategies to further prevent joint damage. Furthermore, additional radiographic follow-up might be needed for joints with (frequent) clinical inflammation.”

Disclosure: Some of the study authors have declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.