18 March 2019

No benefit in regular MRIs for RA

Clinical Rheumatology

An MRI-guided treatment plan does not appear to improve the management of rheumatoid arthritis over and above a standard clinical treat-to-target strategy.

In fact, in a RCT of 200 patients with rheumatoid arthritis in clinical remission, not only did Danish researchers find no significant benefits of the MRI-guided treatments, but there were substantially more dropouts from treatment, intensified treatments and serious adverse events in the intervention arm.

All patients in the study were treated to target, but half the patients used a conventional DAS28-CRP–guided strategy, while the other half used an MRI-guided strategy.

Nearly all of the study participants were in remission at baseline, but this study tried to improve symptoms further by treating sub-clinical inflammation in the MRI arm.

The study participants were assessed every four months for two years. Treatment was intra-articular glucocorticoids administered to each clinically swollen joint, with the treatment escalated according to an algorithm if the target was not reached.

After two years, there was no significant difference between the two groups in terms of the proportion of patients in remission (which was defined as DAS28-CRP < 2.6 and with no radiographic progression from baseline).

“These findings do not support the use of an MRI-guided strategy for treating patients with RA,” the authors said.

Seventeen patients in the MRI group experienced serious adverse events, compared with only six in the conventional group.

This was probably related to the more intensive therapy administered in effort to eliminate MRI measures of inflammation, the authors said. (Treatment was intensified for 73% of the MRI group vs only 17% of the conventional group, with 46% vs 2% progressing to biologics.)

What’s more, the MRI group had 24 dropouts whereas the conventional group only had five.

Rheumatologists have cautiously welcomed the study published in JAMA, as the findings suggest clinical assessment does not need to be supplemented with regular MRI imaging for subclinical inflammation as standard practice.

Commenting on the study, Melbourne rheumatologist Dr David Liew said the research hit on a “deep insecurity” in the profession.

“We’ve lived for some time now with the idea that if we can drive a patient’s RA into remission, we can preserve their joints in the long term,” Dr Liew said.

“But we’ve always had a suspicion that we might be missing low-grade disease activity and it’s hard to know how much that really matters. Does inflammation that we can’t feel but which we can see on MRI matter for long-term outcomes?”

He said the study gave reassurance that specialists need not worry about intensifying therapy when clinical remission is achieved.

“Once we have that low disease activity and we can’t feel clinical synovitis, we don’t need to keep upping the ante in therapy, and in fact that leads to worse outcomes through side effects.

“It means there’s no need to perform serial MRIs on patients after diagnosis. But this doesn’t necessarily translate to ultrasound.”

Adelaide University Associate Professor Maureen Rischmueller also welcomed the finding that clinical assessment was sufficient, though she noted the groups were slightly mismatched at baseline, with more remission in the conventional arm.

“MRI is a costly investigation and not easily accessible to all,” she said. “Besides, the MRI-guided algorithm led to significantly more patients being escalated to biologics, who may not have needed them, with an associated increase in adverse events.

“In view of the fact that fewer patients were in remission at baseline in the MRI-guided group, however, and the trend to improved secondary outcomes in the MRI-guided group, I anticipate that future studies may demonstrate utility in this approach, in contradiction to the current study.”

JAMA 2019, February 5