Ultrasounds and MRI are both used to monitor inflammation activity in rheumatoid arthritis, but their value in refining future treatment strategies has so far been unknown.
Inflammation detected by ultrasound or MRI is linked with certain aspects of future progression in rheumatoid arthritis (RA), according to a new study.
However, the findings are unlikely to impact clinical practice, because prediction models using imaging information do not perform significantly better than those using only routine clinical and laboratory measures, the authors wrote.
Published in RMD Open, the 2-year study sought to determine if inflammation detected by imaging at the onset of RA can predict progression or poor response to methotrexate, and to see if subclinical inflammation in remission is predictive of future trends as well.
Data for the study came from a 24-month, multicenter, randomized trial comparing the outcomes of an approach guided by ultrasound with a conventionally guided treat-to-target strategy in early RA.
Out of 230 patients, 218 were included in the final analysis. They were all treated according to current recommendations for disease-modifying antirheumatic drugs, with methotrexate starting at 15 mg/week and rising to 20 mg/week by week 5, with bridging prednisolone.
The strategy also included increasing methotrexate to 25 mg/week, triple conventional synthetic DMARD (methotrexate/sulfasalazine/hydroxychloroquine), and biologics.
In the conventional treatment arm, the decision to adjust therapy was based on the Disease Activity Score (DAS); the treatment target was DAS <1.6 and and no swollen joints.
There were 13 study visits over 2 years. MRI of dominant wrist and hand was performed at 0, 3, 6, 12, 16 and 24 months. Ultrasounds were performed at baseline, 12, and 24 months.
Baseline imaging-based inflammation measures were evaluated as predictors for early methotrexate failure and erosive progression. MRI erosive progression was defined as increase ≥1 units for the MRI erosion score during the second year, and treatment escalation was defined as moving to a higher level of treatment during the second year. Radiographic erosive progression was defined as an increase of ≥1 units for the vdHSS erosion score during the second year. Multivariate regression was used to adjust for clinical, laboratory and radiographic measures.
Imaging measures were analyzed as predictors of treatment escalation and erosive progression during the second year for patients who had achieved remission. The added value of imaging in prediction models was assessed using receiver operating characteristic analyses.
After 1 year of treat-to-target therapy, most patients with RA in clinical remission had some degree of joint inflammation on MRI and ultrasound, and the level of MRI inflammation was associated with treatment escalation and radiographic progression in the following year.
In addition, MRI inflammation at the time treatment began was linked with subsequent MRI erosive progression and ultrasound inflammation with radiographic erosive progression. But the additional imaging information did not substantially improve prediction models based on routine clinical and demographic measures.
Early methotrexate failure was not found to be linked with any imaging inflammation measure.
"In future studies, it would be of interest to perform comprehensive cost–benefit analyses, examining the cost of MRI and ultrasound examinations in relation to long-term medical treatment expenses, clinical and functional outcomes," the authors wrote.
Sundin U, Paulshus Sundlisater N, Aga AB, et al. Value of MRI and ultrasound for prediction of therapeutic response and erosive progression in patients with early rheumatoid arthritis managed by an aggressive treat-to-target strategy. RMD Open. 2021;7:e001525. doi:10.1136/rmdopen-2020-001525