This article is more than 5 years old. Information may no longer be current.

Study: RF, ACPA antibody information may not be sufficient to predict progression to RA

Add topic to email alerts

Receive an email when new articles are posted on

Please provide your email address to receive an email when new articles are posted on .

Subscribe

Added to email alerts

You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

Back to Healio

We were unable to process your request. Please try again later. If you continue to have this issue please contact customerservice@slackinc.com.

Back to Healio

WASHINGTON — Although 70% of patients with arthralgia who were positive for both rheumatoid factor and anti-citrullinated protein antibodies progressed to rheumatoid arthritis, researchers of a study presented at the American College of Rheumatology Annual Meeting suggested this antibody information may not be sufficient to fully predict progression to disease.

Robin M. ten Brinck, MD, and colleagues investigated associations between arthritis development in patients with arthralgia and rheumatoid factor (RF), anti-citrullinated protein antibodies (ACPA) and anti-carbamylated protein antibodies. The study included 255 patients with clinically suspect arthralgia for less than 1 year and one or more antibodies.

“This study focused on the time in disease progression when patients are experiencing symptoms of arthralgia that are detectable on examination but are not considered to be at risk for [rheumatoid arthritis] RA progression,” he said.

Clinical arthritis developed in 45 patients. Univariate analysis results indicated RF (hazard ratio [HR] = 4.8), ACPA (HR = 7.9) and anti-carbamylated protein (HR = 3.7) antibodies were all significantly associated with the development of RA. In the multivariate analysis that accounted for the same markers, only ACPA demonstrated a significant association with onset of RA (HR = 5).

“Once ACPA is positive, there does not seem to be much difference if [the] rheumatoid factor is also positive,” ten Brinck said. “There was not much of an additive element if [the] rheumatoid factor is also positive. Most of the ACPA-positive patients progressed to RA relatively early.”

The researchers also stratified patients in groups with different combinations of RF and ACPA. The biggest risk was observed in patients who were positive for both RF and ACPA compared to those who were negative for both markers (HR = 9.5). When patients who were RF-negative and ACPA-positive were compared with patients who were RF-positive and ACPA-negative, no significant differences were reported in terms of RA development.

Nearly 70% of individuals who were positive for both RF and ACPA progressed to clinical arthritis. However, the remainder of those with positivity for both did not progress to RA through 96 weeks.

“We observed that 33% of ACPA- and RF-positive patients will not progress to RA within 2 years,” ten Brinck said.

The researchers looked more closely at the patients who did not progress to RA, according to ten Brink.

“We wondered about them,” he said. “But we observed no differences between them and the patients who progressed at baseline.”

He added, “Autoantibody-positive alone is not sufficient to predict progression to rheumatoid arthritis.” – by Rob Volansky

Reference:

ten Brinck RM, et al. Abstract #1035. Presented at: The American College of Rheumatology Annual Meeting; Nov. 11-16, 2016. Washington.

Disclosure: ten Brinck reports no relevant financial disclosures.