Exactly How Wide is RA "Window of Opportunity"?

January 12, 2015

Early treatment is clearly better in RA, but there has not been agreement about the optimal time frame. A new study clarifies the issue.

van Nies JAB, Tsonaka RT, Gaujoux-Viala C, et al., Extended report: Evaluating relationships between symptom duration and persistence of rheumatoid arthritis: does a window of opportunity exist? Results on the Leiden Early Arthritis Clinic and ESPOIR cohorts. Ann Rheum Dis Published Online First: 5 January 2015 doi:10.1136/annrheumdis-2014-206047 

For the best odds of achieving remission in rheumatoid arthritis (RA), start treatment within about 4 months after symptoms arise, say these authors.

They clarify the optimal “window of opportunity” after symptom onset for starting treatment.  The study analyzes follow-up data for almost 1,300 patients in two large European studies: the Leiden Early Arthritis Clinic (EAC) and 14-center French ESPOIR.

Previous "window" estimates in the literature range from immediate treatment to 2 years, hovering lately around 3 months (without a logical rationale), the researchers say. 

They looked at chances of achieving sustained remission (lack of joint swelling for a full year) among RA patients treated with conventional disease modifying antirheumatic drugs (DMARDs) and/or methotrexate (MTX). Because the relationship between pre-treatment symptom duration and odds of sustained symptom-free remission is not linear, the study looked for the times of treatment initiation during which the response curve was steepest.

This ranged from 15 to 19 weeks after patients first reported symptoms.

The window opened at 12 weeks for anti-citrullinated peptide antibody-positive (ACPA+) patients and 15 weeks for those with ACPA-negative RA.

The types of DMARDs prescribed had no noteworthy effect on the time results.

About 40% overall (212 patients) achieved sustained 5-year remission. Almost 12% of the EAC patients (n=85/738) and more than 5% of the ESPOIR cohort (n=29/533) enjoyed DMARD-free remission. 

The exact dates that patients in each group began treatment is not known, so the size of the window can't be determined precisely, the authors caution.

“It cannot be concluded that the window ‘is closed’ after this period, but the data of the present cohorts clearly showed that the [effect] on remission was less after this period, and so possibly it ‘starts to close’ at this point in time,” the researchers wrote.

“We do not suggest that DMARD treatment after a certain window is futile, but that initiating a DMARD in this particular window might yield a better outcome,” they add. “In case a patient is identified after this period has passed, DMARD therapy should certainly not be withheld.”