“When you use walking assistance or a device, it pushes you into an MSWS-12 subset, but your performance on actual walking may not be correlated to that,” she said. “Patients can walk very poorly when unassisted, but then you give them a rollator or walker, and their walking performance actually improves, because you have compensated for some of the balance issues, instability, and fear of falling that was affecting their speed and movement. So while their 6MWT score may improve, their MSWS-12 score would worsen.”
The Best Clinical Tool?
These results confirm that the 6MWT is feasible, tolerated, and more precise than the T25FW in patients with MS, including those with severe disease. However, she emphasized, more research is necessary, according to Dr. Goldman.
“We need to learn more about the 6MWT’s responsiveness,” she said. “We want to understand its longitudinal behavior over time relative to other outcome measures and to clinically meaningful change. Finally, we need additional studies to explore the performance of the MSMS-12 at the two bookends of this ambulatory population.”
In response to the concern that the 6MWT is more difficult to perform than the T25FW in a clinical setting, Dr. Goldman replied, “I think there are two different questions that have to be addressed—how we determine efficacy in clinical trials in the research arena and how we manage patients in our practices.
“Using the 6MWT on every patient who comes into the office is a very difficult thing to do—I am the 6MWT champion, and I find it difficult to do in my clinical practice,” she commented.
“But when we consider that we may be discarding drugs with a therapeutic impact that we can’t detect using our current measures, it seems that a little bit of burden may go a long way,” Dr. Goldman continued. “What I’m getting at is not necessarily, ‘How do we manage a patient day-to-day in our clinical practice?’ It’s, ‘What’s the best way to detect if the therapies are effective?’ And I think the tools that we should pick are going to vary depending on the task at hand.”
—Jack Baney